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1.  HIV-1 Transmission during Early Infection in Men Who Have Sex with Men: A Phylodynamic Analysis 
PLoS Medicine  2013;10(12):e1001568.
Erik Volz and colleagues use HIV genetic information from a cohort of men who have sex with men in Detroit, USA to dissect the timing of onward transmission during HIV infection.
Please see later in the article for the Editors' Summary
Background
Conventional epidemiological surveillance of infectious diseases is focused on characterization of incident infections and estimation of the number of prevalent infections. Advances in methods for the analysis of the population-level genetic variation of viruses can potentially provide information about donors, not just recipients, of infection. Genetic sequences from many viruses are increasingly abundant, especially HIV, which is routinely sequenced for surveillance of drug resistance mutations. We conducted a phylodynamic analysis of HIV genetic sequence data and surveillance data from a US population of men who have sex with men (MSM) and estimated incidence and transmission rates by stage of infection.
Methods and Findings
We analyzed 662 HIV-1 subtype B sequences collected between October 14, 2004, and February 24, 2012, from MSM in the Detroit metropolitan area, Michigan. These sequences were cross-referenced with a database of 30,200 patients diagnosed with HIV infection in the state of Michigan, which includes clinical information that is informative about the recency of infection at the time of diagnosis. These data were analyzed using recently developed population genetic methods that have enabled the estimation of transmission rates from the population-level genetic diversity of the virus. We found that genetic data are highly informative about HIV donors in ways that standard surveillance data are not. Genetic data are especially informative about the stage of infection of donors at the point of transmission. We estimate that 44.7% (95% CI, 42.2%–46.4%) of transmissions occur during the first year of infection.
Conclusions
In this study, almost half of transmissions occurred within the first year of HIV infection in MSM. Our conclusions may be sensitive to un-modeled intra-host evolutionary dynamics, un-modeled sexual risk behavior, and uncertainty in the stage of infected hosts at the time of sampling. The intensity of transmission during early infection may have significance for public health interventions based on early treatment of newly diagnosed individuals.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Since the first recorded case of AIDS in 1981, the number of people infected with HIV, the virus that causes AIDS, has risen steadily. About 34 million people are currently HIV-positive, and about 2.5 million people become newly infected with HIV every year. Because HIV is usually transmitted through unprotected sex with an infected partner, individuals can reduce their risk of infection by abstaining from sex, by having only one or a few partners, and by always using condoms. Most people do not become ill immediately after infection with HIV, although some develop a short flu-like illness. The next stage of HIV infection, which may last more than ten years, also has no major symptoms, but during this stage, HIV slowly destroys immune system cells. Eventually, the immune system can no longer fight off infections by other disease-causing organisms, and HIV-positive people then develop one or more life-threatening AIDS-defining conditions, including unusual infections and specific types of cancer. HIV infection can be controlled, but not cured, by taking a daily cocktail of antiretroviral drugs.
Why Was This Study Done?
The design of effective programs to prevent the spread of HIV/AIDS depends on knowing how HIV transmissibility varies over the course of HIV infection. Consider, for example, a prevention strategy that focuses on increasing treatment rates: antiretroviral drugs, in addition to reducing illness and death among HIV-positive people, reduce HIV transmission from HIV-positive individuals. “Treatment as prevention” can only block transmissions that occur after diagnosis and entry into care. However, the transmissibility of HIV per sexual contact depends on a person's viral load, which peaks during early HIV infection, when people are often unaware of their HIV status and may still be following the high-risk patterns of sexual behavior that caused their own infection. Epidemiological surveillance data (information on HIV infections within populations) can be used to estimate how many new HIV infections occur within a population annually (HIV incidence) and the proportion of the population that is HIV-positive (HIV prevalence), but cannot be used to estimate the timing of transmission events. In this study, the researchers use “phylodynamic analysis” to estimate HIV incidence and prevalence and the timing of HIV transmission during infection. HIV, like many other viruses, rapidly accumulates genetic changes. The timing of transmission influences the pattern of these changes. Viral phylodynamic analysis—the quantitative study of how epidemiological, immunological, and evolutionary processes shape viral phylogenies (evolutionary trees)—can therefore provide estimates of transmission dynamics.
What Did the Researchers Do and Find?
The researchers obtained HIV sequence data (collected for routine surveillance of antiretroviral resistance mutations) and epidemiological surveillance data (including information on the stage of infection at diagnosis) for 662 HIV-positive men who have sex with men living in the Detroit metropolitan area of Michigan. They constructed a phylogenetic tree from the sequences using a “relaxed clock” approach and then fitted an epidemiological model (a mathematical model that represents the progress of individual patients through various stages of HIV infection) to the sequence data. Their approach, which integrates surveillance data and genetic data, yielded estimates of HIV incidence and prevalence among the study population similar to those obtained from surveillance data alone. However, it also provided information about HIV transmission that could not be obtained from surveillance data alone. In particular, it allowed the researchers to estimate that, in the current HIV epidemic among men who have sex with men in Detroit, 44.7% of HIV transmissions occur during the first year of infection.
What Do These Findings Mean?
The robustness of these findings depends on the validity of the assumptions included in the researchers' population genetic model and on the accuracy of the data fed into the model, and may not be generalizable to other cities or to other risk groups. Nevertheless, the findings of this analysis, which can be repeated in any setting where HIV sequence data for individual patients can be linked to patient-specific clinical and behavioral information, have important implications for HIV control strategies based on the early treatment of newly diagnosed individuals. Because relatively few infected individuals are diagnosed during early HIV infection, when the HIV transmission rate is high, it is unlikely, suggest the researchers, that the “treatment as prevention” strategy will effectively control the spread of HIV unless there are very high rates of HIV testing and treatment.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001568.
This study is further discussed in a PLOS Medicine Perspective by Timothy Hallett
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS and summaries of recent research findings on HIV care and treatment
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on HIV treatment as prevention (in English and Spanish)
The PLOS Medicine Collection Investigating the Impact of Treatment on New HIV Infections provides more information about HIV treatment as prevention
A PLOS Computational Biology Topic Page (a review article that is a published copy of record of a dynamic version of the article as found in Wikipedia) about viral phylodynamics is available
The US National Institute of Health–funded HIV Sequence Database contains HIV sequences and tools to analyze these sequences
Patient stories about living with HIV/AIDS are available through Avert; the charity website Healthtalkonline also provides personal stories about living with HIV
doi:10.1371/journal.pmed.1001568
PMCID: PMC3858227  PMID: 24339751
2.  Optimal Uses of Antiretrovirals for Prevention in HIV-1 Serodiscordant Heterosexual Couples in South Africa: A Modelling Study 
PLoS Medicine  2011;8(11):e1001123.
Hallett et al use a mathematical model to examine the long-term impact and cost-effectiveness of different pre-exposure prophylaxis (PrEP) strategies for HIV prevention in serodiscordant couples.
Background
Antiretrovirals have substantial promise for HIV-1 prevention, either as antiretroviral treatment (ART) for HIV-1–infected persons to reduce infectiousness, or as pre-exposure prophylaxis (PrEP) for HIV-1–uninfected persons to reduce the possibility of infection with HIV-1. HIV-1 serodiscordant couples in long-term partnerships (one member is infected and the other is uninfected) are a priority for prevention interventions. Earlier ART and PrEP might both reduce HIV-1 transmission in this group, but the merits and synergies of these different approaches have not been analyzed.
Methods and Findings
We constructed a mathematical model to examine the impact and cost-effectiveness of different strategies, including earlier initiation of ART and/or PrEP, for HIV-1 prevention for serodiscordant couples. Although the cost of PrEP is high, the cost per infection averted is significantly offset by future savings in lifelong treatment, especially among couples with multiple partners, low condom use, and a high risk of transmission. In some situations, highly effective PrEP could be cost-saving overall. To keep couples alive and without a new infection, providing PrEP to the uninfected partner could be at least as cost-effective as initiating ART earlier in the infected partner, if the annual cost of PrEP is <40% of the annual cost of ART and PrEP is >70% effective.
Conclusions
Strategic use of PrEP and ART could substantially and cost-effectively reduce HIV-1 transmission in HIV-1 serodiscordant couples. New and forthcoming data on the efficacy of PrEP, the cost of delivery of ART and PrEP, and couples behaviours and preferences will be critical for optimizing the use of antiretrovirals for HIV-1 prevention.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Every year, about 2.5 million people become infected with HIV, the virus that causes AIDS. HIV is usually transmitted through unprotected sex with an HIV-infected partner. It destroys immune system cells (including CD4 cells, a type of lymphocyte), leaving infected individuals susceptible to other infections. There is no cure for AIDS, although HIV can be held in check with antiretroviral therapy (ART), and there is no vaccine that protects against HIV infection. So, to halt the AIDS epidemic, other ways of preventing the spread of HIV are needed. Antiretroviral drugs could potentially be used in two ways to reduce HIV transmission. First, ART could be given to HIV-infected people before they need it for their own health to reduce their infectiousness; the World Health Organization currently recommends that HIV-positive people initiate ART when their CD4 count drops below 350 cells/µl blood but in many African countries ART is only initiated when CD4 counts fall below 200 cells/µl. Second, ART could be given to HIV-uninfected people to reduce acquisition of the virus. This approach—preexposure prophylaxis (PrEP)—has provided protection against HIV transmission in some but not all clinical trials.
Why Was This Study Done?
Couples in long-term relationships where one partner is HIV-positive and the other is HIV-negative (HIV serodiscordant couples) are a priority group for prevention interventions. In sub-Saharan Africa, where most new HIV infections occur, 10%–20% of stable partnerships are serodiscordant and condom use is often low, not least because such couples may want children. Earlier ART or PrEP might reduce HIV transmission in this group but the merits of different approaches have not been analyzed. In this study, the researchers use a mathematical model to examine the long-term impact and cost-effectiveness of different PrEP and ART strategies for HIV prevention in serodiscordant couples.
What Did the Researchers Do and Find?
The researchers constructed a model to simulate HIV infection and disease progression among hypothetical HIV serodiscordant stable heterosexual couples. The model incorporated data from South Africa on couple characteristics, disease progression, ART use, pregnancies, frequency of sex, and contact with other sexual partners, as well as estimates of the effectiveness of PrEP from clinical trials. The researchers used the model to compare the impact on HIV transmission, survival and quality of life, and the cost-effectiveness of no PrEP with four PrEP strategies—always use PrEP after diagnosis of HIV serodiscordancy, use PrEP up to and for a year after ART initiation by the HIV-infected partner (at a CD4 count of ≤200 cells/µl or ≤350 cells/µl), use PrEP only up to ART initiation by the infected partner, and use PrEP only while trying for a baby and during pregnancy. The model predicts, for example, that the cost per infection averted of PrEP used before ART initiation will be offset by future savings in lifelong treatment, particularly among couples with multiple partners, low condom use, and a high risk of transmission. To keep couples alive without the HIV-uninfected partner becoming infected, it could be more cost-effective to provide PrEP to the uninfected partner than to initiate ART earlier in the infected partner, provided the annual cost of PrEP is less than 40% of the annual cost of ART and PrEP is more than 70% effective. Finally, if PREP is 30%–60% effective, the most cost-effective strategy for couples could be to use PrEP in the uninfected partner prior to ART initiation in the infected partner at a CD4 count ≤350 cells/µl.
What Do These Findings Mean?
These findings suggest that the strategic use of PrEP and ART could cost-effectively reduce HIV transmission in HIV serodiscordant stable heterosexual couples in sub-Saharan Africa. The accuracy of these findings depends on the assumptions included in the mathematical model and on the data fed into it. In particular, the interpretation of these results is complicated by uncertainties in the likely cost of PrEP and the “real-world” effectiveness of PrEP. Nevertheless, these findings suggest that PrEP may become a valuable addition in some settings to existing approaches for HIV prevention such as condom promotion and male circumcision programs. Moreover, additional simulations with this mathematical model using more accurate information on the costs and effectiveness of PrEP could assist in future policy making decisions.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001123.
Information is available from the US National Institute of Allergy and infectious diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS, summaries of recent research findings on HIV care and treatment, and a section on PrEP
Information is available from Avert, an international AIDS charity on many aspects of HIV/AIDS, including information on all aspects of HIV prevention, and on HIV/AIDS in Africa (in English and Spanish)
AVAC Global Advocacy for HIV Prevention provides up-to-date information on all aspects of HIV prevention, including PrEP
The US Centers for Disease Control and Prevention also has information on PrEP
WHO provides information about antiretroviral therapy
Patient stories about living with HIV/AIDS are available through Avert and through the charity website Healthtalkonline
doi:10.1371/journal.pmed.1001123
PMCID: PMC3217021  PMID: 22110407
3.  Incident HIV during Pregnancy and Postpartum and Risk of Mother-to-Child HIV Transmission: A Systematic Review and Meta-Analysis 
PLoS Medicine  2014;11(2):e1001608.
Alison Drake and colleagues conduct a systematic review and meta-analysis to estimate maternal HIV incidence during pregnancy and the postpartum period and to compare mother-to-child HIV transmission risk among women with incident versus chronic infection.
Please see later in the article for the Editors' Summary
Background
Women may have persistent risk of HIV acquisition during pregnancy and postpartum. Estimating risk of HIV during these periods is important to inform optimal prevention approaches. We performed a systematic review and meta-analysis to estimate maternal HIV incidence during pregnancy/postpartum and to compare mother-to-child HIV transmission (MTCT) risk among women with incident versus chronic infection.
Methods and Findings
We searched PubMed, Embase, and AIDS-related conference abstracts between January 1, 1980, and October 31, 2013, for articles and abstracts describing HIV acquisition during pregnancy/postpartum. The inclusion criterion was studies with data on recent HIV during pregnancy/postpartum. Random effects models were constructed to pool HIV incidence rates, cumulative HIV incidence, hazard ratios (HRs), or odds ratios (ORs) summarizing the association between pregnancy/postpartum status and HIV incidence, and MTCT risk and rates. Overall, 1,176 studies met the search criteria, of which 78 met the inclusion criterion, and 47 contributed data. Using data from 19 cohorts representing 22,803 total person-years, the pooled HIV incidence rate during pregnancy/postpartum was 3.8/100 person-years (95% CI 3.0–4.6): 4.7/100 person-years during pregnancy and 2.9/100 person-years postpartum (p = 0.18). Pooled cumulative HIV incidence was significantly higher in African than non-African countries (3.6% versus 0.3%, respectively; p<0.001). Risk of HIV was not significantly higher among pregnant (HR 1.3, 95% CI 0.5–2.1) or postpartum women (HR 1.1, 95% CI 0.6–1.6) than among non-pregnant/non-postpartum women in five studies with available data. In African cohorts, MTCT risk was significantly higher among women with incident versus chronic HIV infection in the postpartum period (OR 2.9, 95% CI 2.2–3.9) or in pregnancy/postpartum periods combined (OR 2.3, 95% CI 1.2–4.4). However, the small number of studies limited power to detect associations and sources of heterogeneity.
Conclusions
Pregnancy and the postpartum period are times of persistent HIV risk, at rates similar to “high risk” cohorts. MTCT risk was elevated among women with incident infections. Detection and prevention of incident HIV in pregnancy/postpartum should be prioritized, and is critical to decrease MTCT.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Worldwide, about 3.4 million children younger than 15 years old (mostly living in sub-Saharan Africa) are infected with HIV, the virus that causes AIDS by gradually destroying immune system cells, thereby leaving infected individuals susceptible to other serious infections. In 2012 alone, 230,000 children (more than 700 every day) were newly infected with HIV. Most HIV infections among children are the result of mother-to-child HIV transmission (MTCT) during pregnancy, delivery, or breastfeeding. The rate of MTCT (and deaths among HIV-positive pregnant women from complications related to HIV infection) can be greatly reduced by testing women for HIV infection during pregnancy (antenatal HIV testing), treating HIV-positive women with antiretroviral drugs (ARVs, powerful drugs that control HIV replication and allow the immune system to recover) during pregnancy, delivery, and breastfeeding, and giving ARVs to their newborn babies.
Why Was This Study Done?
The World Health Organization and the Joint United Nations Programme on HIV/AIDS (UNAIDS) have developed a global plan that aims to move towards eliminating new HIV infections among children by 2015 and towards keeping their mothers alive. To ensure the plan's success, the incidence of HIV (the number of new infections) among women and the rate of MTCT must be reduced by increasing ARV uptake by mothers and their infants for the prevention of MTCT. However, the risk of HIV infection among pregnant women and among women who have recently given birth (postpartum women) is poorly understood because, although guidelines recommend repeat HIV testing during late pregnancy or at delivery in settings where HIV infection is common, pregnant women are often tested only once for HIV infection. The lack of retesting represents a missed opportunity to identify pregnant and postpartum women who have recently acquired HIV and to prevent MTCT by initiating ARV therapy. In this systematic review (a study that uses predefined criteria to identify all the research on a given topic) and meta-analysis (a study that uses statistical methods to combine the results of several studies), the researchers estimate maternal HIV incidence during pregnancy and the postpartum period, and compare the risk of MTCT among women with incident (new) and chronic (long-standing) HIV infection.
What Did the Researchers Do and Find?
The researchers identified 47 studies (35 undertaken in Africa) that examined recent HIV acquisition by women during pregnancy and the 12-month postpartum period. They used random effects statistical models to estimate the pooled HIV incidence rate and cumulative HIV incidence (the number of new infections per number of people at risk), and the association between pregnancy/postpartum status and HIV incidence and MTCT risk and rates. The pooled HIV incidence rate among pregnant/postpartum women estimated from 19 studies (all from sub-Saharan Africa) that reported HIV incidence rates was 3.8/100 person-years. The pooled cumulative HIV incidence was significantly higher in African countries than in non-African countries (3.6% and 0.3%, respectively; a “significant” difference is one that is unlikely to arise by chance). In the five studies that provided suitable data, the risk of HIV acquisition was similar in pregnant, postpartum, and non-pregnant/non-postpartum women. Finally, among African women, the risk of MTCT was 2.9-fold higher during the postpartum period among those who had recently acquired HIV than among those with chronic HIV infection, and 2.3-fold higher during the pregnancy/postpartum periods combined.
What Do These Findings Mean?
These results suggest that women living in regions where HIV infection is common are at high risk of acquiring HIV infection during pregnancy and the postpartum period and that mothers who acquire HIV during pregnancy or postpartum are more likely to pass the infection on to their offspring than mothers with chronic HIV infections. However, the small number of studies included in this meta-analysis and the use of heterogeneous research methodologies in these studies may limit the accuracy of these findings. Nevertheless, these findings have important implications for the global plan to eliminate HIV infections in children. First, they suggest that women living in regions where HIV infection is common should be offered repeat HIV testing (using sensitive methods to enhance early detection of infection) during pregnancy and in the postpartum period to detect incident HIV infections, and should be promptly referred to HIV care and treatment. Second, they suggest that prevention of HIV transmission during pregnancy and postpartum should be prioritized, for example, by counseling women about the need to use condoms to prevent transmission during this period of their lives.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001608.
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS and summaries of recent research findings on HIV care and treatment
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on children and HIV/AIDS and on the prevention of mother-to-child transmission of HIV (in English and Spanish)
The 2013 UNAIDS World AIDS Day Report provides information about the AIDS epidemic and efforts to halt it; the 2013 UNAIDS Progress Report on the Global Plan provides information on progress towards eliminating new HIV infections among children; the UNAIDS Believe it. Do it website provides information about the campaign to support the UNAIDS global plan
Personal stories about living with HIV/AIDS, including stories from young people infected with HIV, are available through Avert, NAM/aidsmap, and Healthtalkonline
doi:10.1371/journal.pmed.1001608
PMCID: PMC3934828  PMID: 24586123
4.  Antigen Load and Viral Sequence Diversification Determine the Functional Profile of HIV-1–Specific CD8+ T Cells 
PLoS Medicine  2008;5(5):e100.
Background
Virus-specific CD8+ T lymphocytes play a key role in the initial reduction of peak viremia during acute viral infections, but display signs of increasing dysfunction and exhaustion under conditions of chronic antigen persistence. It has been suggested that virus-specific CD8+ T cells with a “polyfunctional” profile, defined by the capacity to secrete multiple cytokines or chemokines, are most competent in controlling viral replication in chronic HIV-1 infection. We used HIV-1 infection as a model of chronic persistent viral infection to investigate the process of exhaustion and dysfunction of virus-specific CD8+ T cell responses on the single-epitope level over time, starting in primary HIV-1 infection.
Methods and Findings
We longitudinally analyzed the polyfunctional epitope-specific CD8+ T cell responses of 18 patients during primary HIV-1 infection before and after therapy initiation or sequence variation in the targeted epitope. Epitope-specific CD8+ T cells responded with multiple effector functions to antigenic stimulation during primary HIV-1 infection, but lost their polyfunctional capacity in response to antigen and up-regulated programmed death 1 (PD-1) expression with persistent viremic infection. This exhausted phenotype significantly decreased upon removal of stimulation by antigen, either in response to antiretroviral therapy or by reduction of epitope-specific antigen load in the presence of ongoing viral replication, as a consequence of in vivo selection of cytotoxic T lymphocyte escape mutations in the respective epitopes. Monofunctionality increased in CD8+ T cell responses directed against conserved epitopes from 49% (95% confidence interval 27%–72%) to 76% (56%–95%) (standard deviation [SD] of the effect size 0.71), while monofunctionality remained stable or slightly decreased for responses directed against escaped epitopes from 61% (47%–75%) to 56% (42%–70%) (SD of the effect size 0.18) (p < 0.05).
Conclusion
These data suggest that persistence of antigen can be the cause, rather than the consequence, of the functional impairment of virus-specific T cell responses observed during chronic HIV-1 infection, and underscore the importance of evaluating autologous viral sequences in studies aimed at investigating the relationship between virus-specific immunity and associated pathogenesis.
Marcus Altfeld and colleagues suggest that the exhaustion of virus-specific CD8+ T cells during chronic HIV infection likely results from the persistence of antigen.
Editors' Summary
Background.
Viruses are small infectious agents responsible for many human diseases, including acquired immunodeficiency syndrome (AIDS). Like other viruses, the human immunodeficiency virus 1 (HIV-1; the cause of AIDS) enters human cells and uses the cellular machinery to replicate before bursting out of its temporary home. During the initial stage of HIV infection, a particular group of cells in the human immune system, CD8+ T cells, are thought to be important in controlling the level of the virus. These immune system cells recognize pieces of viral protein called antigens displayed on the surface of infected cells; different subsets of CD8+ T cells recognize different antigens. When a CD8+ T cell recognizes its specific antigen (or more accurately, a small part of the antigen called an “epitope”), it releases cytotoxins (which kill the infected cells) and cytokines, proteins that stimulate CD8+ T cell proliferation and activate other parts of the immune system. With many viruses, when a person first becomes infected (an acute viral infection), antigen-specific CD8+ T cells completely clear the infection. But with HIV-1 and some other viruses, these cells do not manage to remove all the viruses from the body and a chronic (long-term) infection develops, during which the immune system is constantly exposed to viral antigen.
Why Was This Study Done?
In HIV-1 infections (and other chronic viral infections), virus-specific CD8+ T cells lose their ability to proliferate, to make cytokines, and to kill infected cells as patients progress to the long-term stages of infection. That is, the virus-specific CD8+ T cells gradually lose their “effector” functions and become functionally impaired or “exhausted.” “Polyfunctional” CD8+ T cells (those that release multiple cytokines in response to antigen) are believed to be essential for an effective CD8+ T cell response, so scientists trying to develop HIV-1 vaccines would like to stimulate the production of this type of cell. To do this they need to understand why these polyfunctional cells are lost during chronic infections. Is their loss the cause or the result of viral persistence? In other words, does the constant presence of viral antigen lead to the exhaustion of CD8+ T cells during chronic HIV infection? In this study, the researchers investigate this question by looking at the polyfunctionality of CD8+ cells responding to several different viral epitopes at various times during HIV-1 infection, starting very early after infection with HIV-1 had occurred.
What Did the Researchers Do and Find?
The researchers enrolled 18 patients recently infected with HIV-1 and analyzed their CD8+ T cell responses to specific epitopes at various times after enrollment using a technique called flow cytometry. They found that the epitope-specific CD8+ cells produced several effector proteins after antigen stimulation during the initial stage of HIV-1 infection, but lost their polyfunctionality in the face of persistent viral infection. The CD8+ T cells also increased their production of programmed death 1 (PD-1), a protein that has been shown to be associated with the functional impairment of CD8+ T cells. Some of the patients began antiretroviral therapy during the study, and the researchers found that this treatment, which reduced the viral load, reversed CD8+ T cell exhaustion. Finally, the appearance in the patients' blood of viruses that had made changes in the specific epitopes recognized by the CD8+ T cells to avoid being killed by these cells, also reversed the exhaustion of the T cells recognizing these particular epitopes.
What Do These Findings Mean?
These findings suggest that the constant presence of HIV-1 antigen causes the functional impairment of virus-specific CD8+ T cell responses during chronic HIV-1 infections. Treatment with antiretroviral drugs reversed this functional impairment by reducing the amount of antigen in the patients. Similarly, the appearance of viruses with altered epitopes, which effectively reduced the amount of antigen recognized by those epitope-specific CD8+ T cells without reducing the viral load, also reversed T cell exhaustion. These results would not have been seen if the functional impairment of CD8+ cells were the cause rather than the result of antigen persistence. By providing new insights into how the T cell response to viruses evolves during persistent viral infections, these findings should help in the design of vaccines against HIV and other viruses that cause chronic viral infections.
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0050100.
Read a related PLoS Medicine Research in Translation article
Learn more from the researchers' Web site, the Partners AIDS Research Center
Wikipedia has a page on cytotoxic T cells (note that Wikipedia is a free online encyclopedia that anyone can edit; available in several languages)
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
HIV InSite has comprehensive information on all aspects of HIV/AIDS, including a detailed article on the immunopathogenesis of HIV infection
NAM, a UK registered charity, provides information about all aspects of HIV and AIDS, including a fact sheet on the stages of HIV infection and on the immune response to HIV
Information is available from Avert, an international AIDS charity, on all aspects of HIV/AIDS, including information on the stages of HIV infection
doi:10.1371/journal.pmed.0050100
PMCID: PMC2365971  PMID: 18462013
5.  Impact of Round-the-Clock, Rapid Oral Fluid HIV Testing of Women in Labor in Rural India 
PLoS Medicine  2008;5(5):e92.
Background
Testing pregnant women for HIV at the time of labor and delivery is the last opportunity for prevention of mother-to-child HIV transmission (PMTCT) measures, particularly in settings where women do not receive adequate antenatal care. However, HIV testing and counseling of pregnant women in labor is a challenge, especially in resource-constrained settings. In India, many rural women present for delivery without any prior antenatal care. Those who do get antenatal care are not always tested for HIV, because of deficiencies in the provision of HIV testing and counseling services. In this context, we investigated the impact of introducing round-the-clock, rapid, point-of-care HIV testing and counseling in a busy labor ward at a tertiary care hospital in rural India.
Methods and Findings
After they provided written informed consent, women admitted to the labor ward of a rural teaching hospital in India were offered two rapid tests on oral fluid and finger-stick specimens (OraQuick Rapid HIV-1/HIV-2 tests, OraSure Technologies). Simultaneously, venous blood was drawn for conventional HIV ELISA testing. Western blot tests were performed for confirmatory testing if women were positive by both rapid tests and dual ELISA, or where test results were discordant. Round-the-clock (24 h, 7 d/wk) abbreviated prepartum and extended postpartum counseling sessions were offered as part of the testing strategy. HIV-positive women were administered PMTCT interventions. Of 1,252 eligible women (age range 18 y to 38 y) approached for consent over a 9 mo period in 2006, 1,222 (98%) accepted HIV testing in the labor ward. Of these, 1,003 (82%) women presented with either no reports or incomplete reports of prior HIV testing results at the time of admission to the labor ward. Of 1,222 women, 15 were diagnosed as HIV-positive (on the basis of two rapid tests, dual ELISA and Western blot), yielding a seroprevalence of 1.23% (95% confidence interval [CI] 0.61%–1.8%). Of the 15 HIV test–positive women, four (27%) had presented with reported HIV status, and 11 (73%) new cases of HIV infection were detected due to rapid testing in the labor room. Thus, 11 HIV-positive women received PMTCT interventions on account of round-the-clock rapid HIV testing and counseling in the labor room. While both OraQuick tests (oral and finger-stick) were 100% specific, one false-negative result was documented (with both oral fluid and finger-stick specimens). Of the 15 HIV-infected women who delivered, 13 infants were HIV seronegative at birth and at 1 and 4 mo after delivery; two HIV-positive infants died within a month of delivery.
Conclusions
In a busy rural labor ward setting in India, we demonstrated that it is feasible to introduce a program of round-the-clock rapid HIV testing, including prepartum and extended postpartum counseling sessions. Our data suggest that the availability of round-the-clock rapid HIV testing resulted in successful documentation of HIV serostatus in a large proportion (82%) of rural women who were unaware of their HIV status when admitted to the labor room. In addition, 11 (73%) of a total of 15 HIV-positive women received PMTCT interventions because of round-the-clock rapid testing in the labor ward. These findings are relevant for PMTCT programs in developing countries.
Nitika Pant Pai and colleagues report the results of offering a round-the-clock rapid HIV testing program in a rural labor ward setting in India.
Editors' Summary
Background.
Since the first reported case of AIDS (acquired immunodeficiency syndrome) in 1981, the number of people infected with the human immunodeficiency virus (HIV), which causes AIDS, has risen steadily. Now, more than 33 million people are infected, almost half of them women. HIV is most often spread through unprotected sex with an infected partner, but mother-to-child transmission (MTCT) of HIV is also an important transmission route. HIV-positive women often pass the virus to their babies during pregnancy, labor and delivery, and breastfeeding, if nothing is done to prevent viral transmission. In developed countries, interventions such as voluntary testing and counseling, safe delivery practices (for example, offering cesarean delivery to HIV-positive women), and antiretroviral treatment of the mother during pregnancy and labor and of her newborn baby have minimized the risk of MTCT. In developing countries, the prevention of MTCT (PMTCT) is much less effective, in part because pregnant women often do not know their HIV status. Consequently, in 2007, nearly half a million children became infected with HIV mainly through MTCT.
Why Was This Study Done?
In many developing countries, women do not receive adequate antenatal care. In India, for example, nearly half the women living in rural areas do not receive any antenatal care until they are in labor. This gives health care providers very little time in which to counsel women about HIV infection, test them for the virus, and start interventions to prevent MTCT. Furthermore, testing pregnant women in labor for HIV and counseling them is a challenge, particularly where resources are limited. In this study, therefore, the researchers investigate the feasibility and impact of introducing round-the-clock, rapid HIV testing and counseling in a busy labor ward in a rural teaching hospital in Sevagram, India.
What Did the Researchers Do and Find?
Women admitted to the labor ward between January and September 2006 were offered two rapid HIV tests—one that used a saliva sample and the other that used blood taken from a finger prick. Blood was also taken from a vein for conventional HIV testing. All the women were given a 15-minute counseling session about how HIV is transmitted, the importance of HIV testing, and information on PMTCT before their child was born (prepartum counseling), and a longer postpartum counseling session. HIV-positive women were given a cesarean delivery where possible and antiretroviral drug treatment to reduce MTCT. 1,222 women admitted to the labor ward during the study period (1,003 of whom did not know their HIV status) accepted HIV testing. Of 15 study participants who were HIV positive, 11 learnt of their HIV status in the labor room. Two babies born to these HIV-positive women were HIV positive and died within a month of delivery; the other 13 babies were HIV negative at birth and at 1 and 4 months after delivery. Finally, the rapid HIV tests missed only one HIV-positive woman (no false-positive results were given), and the time from enrolling a woman into the study through referring her for PMTCT intervention where necessary averaged 40–60 minutes.
What Do These Findings Mean?
These findings show the feasibility and positive impact of the introduction of round-the-clock pre- and postpartum HIV counseling and rapid HIV testing into a busy rural Indian labor ward. Few of the women entering this ward knew their HIV status previously but the introduction of these facilities in this setting successfully informed these women of their HIV status. In addition, the round-the-clock counseling and testing led to 11 women and their babies receiving PMTCT interventions who would otherwise have been missed. These findings need to be confirmed in other settings and the cost-effectiveness and sustainability of this approach for the improvement of PMTCT in developing countries needs to be investigated. Nevertheless, these findings suggest that round-the-clock rapid HIV testing might be an effective and acceptable way to reduce MTCT of HIV in many developing countries.
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0050092.
Read a related PLoS Medicine Perspective article
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS and on HIV infection in women
HIV InSite has comprehensive information on all aspects of HIV/AIDS
Women, Children, and HIV provides extensive information on the prevention of mother-to-child transmission of HIV in developing countries
Information is available from Avert, an international AIDS charity, on HIV and AIDS in India, on women, HIV, and AIDS, and on HIV and AIDS prevention, including the prevention of mother-to-child transmission
AIDSinfo, a service of the US Department of Health and Human Services provides health information for HIV-positive pregnant women (in English and Spanish)
doi:10.1371/journal.pmed.0050092
PMCID: PMC2365974  PMID: 18462011
6.  Bacterial Vaginosis Associated with Increased Risk of Female-to-Male HIV-1 Transmission: A Prospective Cohort Analysis among African Couples 
PLoS Medicine  2012;9(6):e1001251.
In a prospective study, Craig Cohen and colleagues investigate the association between bacterial vaginosis and the risk of female-to-male HIV-1 transmission.
Background
Bacterial vaginosis (BV), a disruption of the normal vaginal flora, has been associated with a 60% increased risk of HIV-1 acquisition in women and higher concentration of HIV-1 RNA in the genital tract of HIV-1–infected women. However, whether BV, which is present in up to half of African HIV-1–infected women, is associated with an increase in HIV-1 transmission to male partners has not been assessed in previous studies.
Methods and Findings
We assessed the association between BV on female-to-male HIV-1 transmission risk in a prospective study of 2,236 HIV-1–seropositive women and their HIV-1 uninfected male partners from seven African countries from a randomized placebo-controlled trial that enrolled heterosexual African adults who were seropositive for both HIV-1 and herpes simplex virus (HSV)-2, and their HIV-1–seronegative partners. Participants were followed for up to 24 months; every three months, vaginal swabs were obtained from female partners for Gram stain and male partners were tested for HIV-1. BV and normal vaginal flora were defined as a Nugent score of 7–10 and 0–3, respectively. To reduce misclassification, HIV-1 sequence analysis of viruses from seroconverters and their partners was performed to determine linkage of HIV-1 transmissions. Overall, 50 incident HIV-1 infections occurred in men in which the HIV-1–infected female partner had an evaluable vaginal Gram stain. HIV-1 incidence in men whose HIV-1–infected female partners had BV was 2.91 versus 0.76 per 100 person-years in men whose female partners had normal vaginal flora (hazard ratio 3.62, 95% CI 1.74–7.52). After controlling for sociodemographic factors, sexual behavior, male circumcision, sexually transmitted infections, pregnancy, and plasma HIV-1 RNA levels in female partners, BV was associated with a greater than 3-fold increased risk of female-to-male HIV-1 transmission (adjusted hazard ratio 3.17, 95% CI 1.37–7.33).
Conclusions
This study identified an association between BV and increased risk of HIV-1 transmission to male partners. Several limitations may affect the generalizability of our results including: all participants underwent couples HIV counseling and testing and enrolled in an HIV-1 prevention trial, and index participants had a baseline CD4 count ≥250 cells/mm3 and were HSV-2 seropositive. Given the high prevalence of BV and the association of BV with increased risk of both female HIV-1 acquisition and transmission found in our study, if this association proves to be causal, BV could be responsible for a substantial proportion of new HIV-1 infections in Africa. Normalization of vaginal flora in HIV-1–infected women could mitigate female-to-male HIV-1 transmission.
Trial Registration: ClinicalTrials.com NCT00194519
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Since the first reported case of AIDS in 1981, the number of people infected with HIV, the virus that causes AIDS, has risen steadily. By the end of 2010, 34 million people were living with HIV/AIDS. At the beginning of the epidemic more men than women were infected with HIV. Now, however, 50% of all adults infected with HIV are women and in sub-Saharan Africa, where two-thirds of HIV-positive people live, women account for 59% of people living with HIV. Moreover, among 15–24 year-olds, women are eight times more likely than men to be HIV-positive. This pattern of infection has developed because most people in sub-Saharan Africa contract HIV through unprotected heterosexual sex. The risk of HIV transmission for both men and women in Africa and elsewhere can be reduced by abstaining from sex, by only having one or a few partners, by always using condoms, and by male circumcision. In addition, several studies suggest that antiretroviral therapy (ART) greatly reduces HIV transmission.
Why Was This Study Done?
Unfortunately, in sub-Saharan Africa, only about a fifth of HIV-positive people are currently receiving ART, which means that there is an urgent need to find other effective ways to reduce HIV transmission in this region. In this prospective cohort study (a type of study that follows a group of people for some time to see which personal characteristics are associated with disease development), the researchers investigate whether bacterial vaginosis—a condition in which harmful bacteria disrupt the normal vaginal flora—increases the risk of female-to-male HIV transmission among African couples. Bacterial vaginosis, which is extremely common in sub-Saharan Africa, has been associated with an increased risk of HIV acquisition in women and induces viral replication and shedding in the vagina in HIV-positive women, which may mean that HIV-positive women with bacterial vaginosis are more likely to transmit HIV to their male partners than women without this condition. If this is the case, then interventions that reduce the incidence of bacterial vaginosis might be valuable HIV prevention strategies.
What Did the Researchers Do and Find?
The researchers analyzed data collected from 2,236 heterosexual African couples enrolled in a clinical trial (the Partners in Prevention HSV/HIV Transmission Study) whose primary aim was to investigate whether suppression of herpes simplex virus infection could prevent HIV transmission. In all the couples, the woman was HIV-positive and the man was initially HIV-negative. The female partners were examined every three months for the presence of bacterial vaginosis and the male partners were tested regularly for HIV infection. The researchers also determined whether the men who became HIV-positive were infected with the same HIV strain as their partner to check that their infection had been acquired from this partner. The HIV incidence in men whose partners had bacterial vaginosis was 2.9 per 100 person-years (that is, 2.9 out of every 100 men became HIV-positive per year) whereas the HIV incidence in men whose partners had a normal vaginal flora was 0.76 per 100 person-years. After controlling for factors that might affect the risk of HIV transmission such as male circumcision and viral levels in female partner's blood, the researchers estimated that bacterial vaginosis was associated with a 3.17-fold increased risk of female-to-male HIV transmission in their study population.
What Do These Findings Mean?
These findings suggest that HIV-positive African women with bacterial vaginosis are more than three times as likely to transmit HIV to their male partners as those with a normal vaginal flora. It is possible that some unknown characteristic of the men in this study might have increased both their own risk of HIV infection and their partner's risk of bacterial vaginosis. Nevertheless, because bacterial vaginosis is so common in Africa (half of the women in this study had bacterial vaginosis at least once during follow-up) and because this condition is associated with both female HIV acquisition and transmission, these findings suggest that bacterial vaginosis could be responsible for a substantial proportion of new HIV infections in Africa. Normalization of vaginal flora in HIV-infected women by frequent presumptive treatment with antimicrobials (treatment with a curative dose of antibiotics without testing for bacterial vaginosis) or possibly by treatment with probiotics (live “good” bacteria) might, therefore, reduce female-to-male HIV transmission in sub-Saharan Africa.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001251.
Information is available from the US National Institute of Allergy and infectious diseases on all aspects of HIV infection and AIDS and on bacterial vaginosis
The US Centers for Disease Control and Prevention has information on all aspects of HIV/AIDS, including specific information about HIV/AIDS and women; it also has information on bacterial vaginosis (in English and Spanish)
NAM/aidsmap provides basic information about HIV/AIDS, and summaries of recent research findings on HIV care and treatment, and information on bacterial vaginosis and HIV transmission (in several languages)
Information is available from Avert, an international AIDS nonprofit group on many aspects of HIV/AIDS, including detailed information on HIV and AIDS prevention, on women, HIV and AIDS and on HIV/AIDS in Africa (in English and Spanish); personal stories of women living with HIV are available; the website Healthtalkonline also provides personal stories about living with HIV
More information about the Partners in Prevention HSV/HIV Transmission Study is available
doi:10.1371/journal.pmed.1001251
PMCID: PMC3383741  PMID: 22745608
7.  Polyclonal B Cell Differentiation and Loss of Gastrointestinal Tract Germinal Centers in the Earliest Stages of HIV-1 Infection 
PLoS Medicine  2009;6(7):e1000107.
Studying the effects of early HIV infection on human antibody responses, M. Anthony Moody and colleagues find rapid polyclonal B cell differentiation and structural damage to gut-associated lymphoid tissue.
Background
The antibody response to HIV-1 does not appear in the plasma until approximately 2–5 weeks after transmission, and neutralizing antibodies to autologous HIV-1 generally do not become detectable until 12 weeks or more after transmission. Moreover, levels of HIV-1–specific antibodies decline on antiretroviral treatment. The mechanisms of this delay in the appearance of anti-HIV-1 antibodies and of their subsequent rapid decline are not known. While the effect of HIV-1 on depletion of gut CD4+ T cells in acute HIV-1 infection is well described, we studied blood and tissue B cells soon after infection to determine the effect of early HIV-1 on these cells.
Methods and Findings
In human participants, we analyzed B cells in blood as early as 17 days after HIV-1 infection, and in terminal ileum inductive and effector microenvironments beginning at 47 days after infection. We found that HIV-1 infection rapidly induced polyclonal activation and terminal differentiation of B cells in blood and in gut-associated lymphoid tissue (GALT) B cells. The specificities of antibodies produced by GALT memory B cells in acute HIV-1 infection (AHI) included not only HIV-1–specific antibodies, but also influenza-specific and autoreactive antibodies, indicating very early onset of HIV-1–induced polyclonal B cell activation. Follicular damage or germinal center loss in terminal ileum Peyer's patches was seen with 88% of follicles exhibiting B or T cell apoptosis and follicular lysis.
Conclusions
Early induction of polyclonal B cell differentiation, coupled with follicular damage and germinal center loss soon after HIV-1 infection, may explain both the high rate of decline in HIV-1–induced antibody responses and the delay in plasma antibody responses to HIV-1.
Please see later in the article for Editors' Summary
Editors' Summary
Background
Acquired immunodeficiency syndrome (AIDS) has killed more than 25 million people since 1981 and more than 30 million people are now infected with the human immunodeficiency virus (HIV), which causes AIDS. HIV infects and kills a type of immune system cell called CD4+ T lymphocytes. These cells are needed to maintain a vigorous immune response, so people infected with HIV eventually become susceptible to other infections and develop full-blown AIDS. However, early during HIV infection, other parts of the immune system attempt to fight off the virus. Soon after infection, immune system cells called B lymphocytes begin to produce HIV-specific antibodies (proteins that recognize viral molecules called antigens). The first antibodies to HIV usually appear two to seven weeks after infection; from about 12 weeks after infection, antibodies are made that can kill the specific HIV type responsible for the infection (neutralizing antibodies).
Why Was This Study Done?
Unfortunately, by this time, it is too late for the antibody (“humoral”) immune response to clear HIV from the body. Indeed, the humoral immune response to HIV is very slow; for most viruses, neutralizing antibodies appear within days of infection. To help them design an effective HIV vaccine, scientists need to understand how the virus delays humoral responses to HIV infection (and how it later causes the production of HIV-specific antibodies to decline). Little is known, however, about the early effects of HIV infection on B lymphocytes. These cells are born and mature in the bone marrow. “Naïve” B lymphocytes, each of which carries an antigen-specific receptor (a protein that binds to a specific antigen), then enter the blood and circulate around the body, passing through the “peripheral lymphoid organs”. Exposure to antigens in these organs, which include lymph nodes and gut-associated lymphoid tissues, activates the subset of B lymphocytes that recognize the specific antigens that are present. Finally, with the help of activated T lymphocytes, the activated B lymphocytes proliferate and change (differentiate) into antibody-secreting cells and memory B lymphocytes (which respond more quickly to antigen than naïve B lymphocytes). In this study, the researchers investigate the effects of early HIV-1 infection on B lymphocytes in blood and in gut-associated lymphoid tissues.
What Did the Researchers Do and Find?
The researchers collected blood from patients as early as 17 days after HIV-1 infection and tissue samples from the lower portion of the small intestine (a region rich in gut-associated lymphoid structures called Peyer's patches) from 47 days after infection onward. When they analyzed the B lymphocytes in these samples (which were collected during two trials organized by the US Center for HIV/AIDS Vaccine Immunology [CHAVI]), they found that HIV-1 infection rapidly induced the activation of many different B cells that recognized a variety of antigens (polyclonal activation), as well as the appearance of differentiated B cells in blood and in gut-associated lymphoid tissue. The B lymphocytes that were activated in the gut made HIV-specific antibodies but also antibodies against unrelated antigens (such as flu virus proteins). Finally, the structure of Peyer's patches was altered early in HIV-1 infection. More specifically, most of the lymphoid follicles (organized collections of lymphocytes and antigen-presenting cells) in the Peyer's patches showed signs of damage and T- and B-lymphocyte death and the number of germinal centers (regions in lymphoid follicles in which B lymphocytes proliferate) was reduced.
What Do These Findings Mean?
Although the depletion of gut-associated CD4+ T lymphocytes in early HIV-1 infection is well known, these new results demonstrate the effects of early HIV-1 infection on gut-associated and circulating B lymphocytes. The results of this study are limited by the methods used to analyze the antibodies induced by HIV infection and by only taking tissue samples from one region of the gut. Nevertheless, the findings of polyclonal B-cell activation and damage to gut-associated lymphoid follicles soon after HIV-1 infection may have implications for HIV-1 vaccine design. Specifically, these findings suggest that an effective HIV-1 vaccine will need to ensure that significant levels of neutralizing antibodies are present in people before HIV-1 infection and that other protective immune defenses are fully primed so that, in the event of HIV-1 infection, the virus can be dealt with effectively before it disables any part of the immune system.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000107.
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
HIV InSite has comprehensive information on all aspects of HIV/AIDS, including an article about how HIV-1 infection affects the immune system
Information is available from Avert, an international AIDS charity on many aspects of HIV/AIDS, including information on the stages of HIV infection, and on AIDS vaccines (in English and Spanish)
The US Center for HIV/AIDS Vaccine Immunology (CHAVI) Web site provides information on research designed to solve major problems in HIV vaccine development and design
doi:10.1371/journal.pmed.1000107
PMCID: PMC2702159  PMID: 19582166
8.  Towards Universal Voluntary HIV Testing and Counselling: A Systematic Review and Meta-Analysis of Community-Based Approaches 
PLoS Medicine  2013;10(8):e1001496.
In a systematic review and meta-analysis, Amitabh Suthar and colleagues describe the evidence base for different HIV testing and counseling services provided outside of health facilities.
Please see later in the article for the Editors' Summary
Background
Effective national and global HIV responses require a significant expansion of HIV testing and counselling (HTC) to expand access to prevention and care. Facility-based HTC, while essential, is unlikely to meet national and global targets on its own. This article systematically reviews the evidence for community-based HTC.
Methods and Findings
PubMed was searched on 4 March 2013, clinical trial registries were searched on 3 September 2012, and Embase and the World Health Organization Global Index Medicus were searched on 10 April 2012 for studies including community-based HTC (i.e., HTC outside of health facilities). Randomised controlled trials, and observational studies were eligible if they included a community-based testing approach and reported one or more of the following outcomes: uptake, proportion receiving their first HIV test, CD4 value at diagnosis, linkage to care, HIV positivity rate, HTC coverage, HIV incidence, or cost per person tested (outcomes are defined fully in the text). The following community-based HTC approaches were reviewed: (1) door-to-door testing (systematically offering HTC to homes in a catchment area), (2) mobile testing for the general population (offering HTC via a mobile HTC service), (3) index testing (offering HTC to household members of people with HIV and persons who may have been exposed to HIV), (4) mobile testing for men who have sex with men, (5) mobile testing for people who inject drugs, (6) mobile testing for female sex workers, (7) mobile testing for adolescents, (8) self-testing, (9) workplace HTC, (10) church-based HTC, and (11) school-based HTC. The Newcastle-Ottawa Quality Assessment Scale and the Cochrane Collaboration's “risk of bias” tool were used to assess the risk of bias in studies with a comparator arm included in pooled estimates.
 117 studies, including 864,651 participants completing HTC, met the inclusion criteria. The percentage of people offered community-based HTC who accepted HTC was as follows: index testing, 88% of 12,052 participants; self-testing, 87% of 1,839 participants; mobile testing, 87% of 79,475 participants; door-to-door testing, 80% of 555,267 participants; workplace testing, 67% of 62,406 participants; and school-based testing, 62% of 2,593 participants. Mobile HTC uptake among key populations (men who have sex with men, people who inject drugs, female sex workers, and adolescents) ranged from 9% to 100% (among 41,110 participants across studies), with heterogeneity related to how testing was offered. Community-based approaches increased HTC uptake (relative risk [RR] 10.65, 95% confidence interval [CI] 6.27–18.08), the proportion of first-time testers (RR 1.23, 95% CI 1.06–1.42), and the proportion of participants with CD4 counts above 350 cells/µl (RR 1.42, 95% CI 1.16–1.74), and obtained a lower positivity rate (RR 0.59, 95% CI 0.37–0.96), relative to facility-based approaches. 80% (95% CI 75%–85%) of 5,832 community-based HTC participants obtained a CD4 measurement following HIV diagnosis, and 73% (95% CI 61%–85%) of 527 community-based HTC participants initiated antiretroviral therapy following a CD4 measurement indicating eligibility. The data on linking participants without HIV to prevention services were limited. In low- and middle-income countries, the cost per person tested ranged from US$2–US$126. At the population level, community-based HTC increased HTC coverage (RR 7.07, 95% CI 3.52–14.22) and reduced HIV incidence (RR 0.86, 95% CI 0.73–1.02), although the incidence reduction lacked statistical significance. No studies reported any harm arising as a result of having been tested.
Conclusions
Community-based HTC achieved high rates of HTC uptake, reached people with high CD4 counts, and linked people to care. It also obtained a lower HIV positivity rate relative to facility-based approaches. Further research is needed to further improve acceptability of community-based HTC for key populations. HIV programmes should offer community-based HTC linked to prevention and care, in addition to facility-based HTC, to support increased access to HIV prevention, care, and treatment.
Review Registration
International Prospective Register of Systematic Reviews CRD42012002554
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Three decades into the AIDS epidemic, about 34 million people (most living in resource-limited countries) are infected with HIV, the virus that causes AIDS. Every year another 2.2 million people become infected with HIV, usually through unprotected sex with an infected partner, and about 1.7 million people die. Infection with HIV, which gradually destroys the CD4 lymphocytes and other immune system cells that provide protection from life-threatening infections, is usually diagnosed by looking for antibodies to HIV in the blood or saliva. Disease progression is subsequently monitored in HIV-positive individuals by counting the CD4 cells in their blood. Initiation of antiretroviral drug therapy—a combination of drugs that keeps HIV replication in check but that does not cure the infection—is recommended when an individual's CD4 count falls below 500 cells/µl of blood or when he or she develops signs of severe or advanced disease, such as unusual infections.
Why Was This Study Done?
As part of intensified efforts to eliminate HIV/AIDS, United Nations member states recently set several HIV-related targets to be achieved by 2015, including reduced transmission of HIV and increased delivery of antiretroviral therapy. These targets can only be achieved if there is a large expansion in HIV testing and counseling (HTC) and increased access to HIV prevention and care services. The World Health Organization currently recommends that everyone attending a healthcare facility in regions where there is a generalized HIV epidemic (defined as when 1% or more of the general population is HIV-positive) should be offered HTC. However, many people rarely visit healthcare facilities, and others refuse “facility-based” HTC because they fear stigmatization and discrimination. Thus, facility-based HTC alone is unlikely to be sufficient to enable national and global HIV targets to be reached. In this systematic review and meta-analysis, the researchers evaluate the performance of community-based HTC approaches such as index testing (offering HTC to the sexual and injecting partners and household members of people with HIV), mobile testing (offering HTC through a service that visits shopping centers and other public facilities), and door-to-door testing (systematically offering HTC to homes in a catchment area). A systematic review uses predefined criteria to identify all the research on a given topic; meta-analysis combines the results of several studies.
What Did the Researchers Do and Find?
The researchers identified 117 studies (most undertaken in Africa and North America) involving 864,651 participants that evaluated community-based HTC approaches. Among these studies, the percentage of people offered community-based HTC who accepted it (HTC uptake) was 88% for index testing, 87% for self-testing, 80% for door-to-door testing, 67% for workplace testing, and 62% for school-based testing. Compared to facility-based approaches, community-based approaches increased the chances of an individual's CD4 count being above 350 cells/µl at diagnosis (an important observation because early diagnosis improves subsequent outcomes) but had a lower positivity rate, possibly because people with symptoms of HIV are more likely to visit healthcare facilities than healthy individuals. Importantly, 80% of participants in the community-based HTC studies had their CD4 count measured after HIV diagnosis, and 73% of the participants initiated antiretroviral therapy after their CD4 count fell below national eligibility criteria; both these observations suggest that community-based HTC successfully linked people to care. Finally, offering community-based HTC approaches in addition to facility-based approaches increased HTC coverage seven-fold at the population level.
What Do These Findings Mean?
These findings show that community-based HTC can achieve high HTC uptake rates and can reach HIV-positive individuals earlier, when they still have high CD4 counts. Importantly, they also suggest that the level of linkage to care of community-based HTC is similar to that of facility-based HTC. Although the lower positivity rate of community-based HTC approaches means that more people need to be tested with these approaches than with facility-based HTC to identify the same number of HIV-positive individuals, this downside of community-based HTC is likely to be offset by the earlier identification of HIV-positive individuals, which should improve life expectancy and reduce HIV transmission at the population level. Although further studies are needed to evaluate community-based HTC in other regions of the world, these findings suggest that offering community-based HTC in HIV programs in addition to facility-based testing should support the increased access to HIV prevention and care that is required for the intensification of HIV/AIDS elimination efforts.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001496.
The World Health Organization provides information on all aspects of HIV/AIDS, including information on counseling and testing (in several languages)
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS and summaries of recent research findings on HIV care and treatment
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on the global HIV/AIDS epidemic, on HIV testing, and on HIV transmission and testing (in English and Spanish)
The UK National Health Service Choices website provides information (including personal stories) about HIV and AIDS
The World AIDS Day Report 2012 provides up-to-date information about the AIDS epidemic and efforts to halt it
Patient stories about living with HIV/AIDS are available through Avert; the nonprofit website Healthtalkonline also provides personal stories about living with HIV, including stories about getting a diagnosis
doi:10.1371/journal.pmed.1001496
PMCID: PMC3742447  PMID: 23966838
9.  Risk Factors and Outcomes for Late Presentation for HIV-Positive Persons in Europe: Results from the Collaboration of Observational HIV Epidemiological Research Europe Study (COHERE) 
PLoS Medicine  2013;10(9):e1001510.
Amanda Mocroft and colleagues investigate risk factors and health outcomes associated with diagnosis at a late stage of infection in individuals across Europe.
Please see later in the article for the Editors' Summary
Background
Few studies have monitored late presentation (LP) of HIV infection over the European continent, including Eastern Europe. Study objectives were to explore the impact of LP on AIDS and mortality.
Methods and Findings
LP was defined in Collaboration of Observational HIV Epidemiological Research Europe (COHERE) as HIV diagnosis with a CD4 count <350/mm3 or an AIDS diagnosis within 6 months of HIV diagnosis among persons presenting for care between 1 January 2000 and 30 June 2011. Logistic regression was used to identify factors associated with LP and Poisson regression to explore the impact on AIDS/death. 84,524 individuals from 23 cohorts in 35 countries contributed data; 45,488 were LP (53.8%). LP was highest in heterosexual males (66.1%), Southern European countries (57.0%), and persons originating from Africa (65.1%). LP decreased from 57.3% in 2000 to 51.7% in 2010/2011 (adjusted odds ratio [aOR] 0.96; 95% CI 0.95–0.97). LP decreased over time in both Central and Northern Europe among homosexual men, and male and female heterosexuals, but increased over time for female heterosexuals and male intravenous drug users (IDUs) from Southern Europe and in male and female IDUs from Eastern Europe. 8,187 AIDS/deaths occurred during 327,003 person-years of follow-up. In the first year after HIV diagnosis, LP was associated with over a 13-fold increased incidence of AIDS/death in Southern Europe (adjusted incidence rate ratio [aIRR] 13.02; 95% CI 8.19–20.70) and over a 6-fold increased rate in Eastern Europe (aIRR 6.64; 95% CI 3.55–12.43).
Conclusions
LP has decreased over time across Europe, but remains a significant issue in the region in all HIV exposure groups. LP increased in male IDUs and female heterosexuals from Southern Europe and IDUs in Eastern Europe. LP was associated with an increased rate of AIDS/deaths, particularly in the first year after HIV diagnosis, with significant variation across Europe. Earlier and more widespread testing, timely referrals after testing positive, and improved retention in care strategies are required to further reduce the incidence of LP.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Every year about 2.5 million people become newly infected with HIV, the virus that causes AIDS. HIV can be transmitted through unprotected sex with an infected partner, from an HIV-positive mother to her unborn baby, or through injection of drugs. Most people do not become ill immediately after infection with HIV although some develop a short influenza-like illness. The next stage of the HIV infection, which may last up to 10 years, also has no major symptoms but, during this stage, HIV slowly destroys immune system cells, including CD4 cells, a type of lymphocyte. Eventually, when the immune system is unable to fight off infections by other disease-causing organisms, HIV-positive people develop AIDS-defining conditions—unusual viral, bacterial, and fungal infections and unusual tumors. Progression to AIDS occurs when any severe AIDS-defining condition is diagnosed, when the CD4 count in the blood falls below 200 cells/mm3, or when CD4 cells account for fewer than 15% of lymphocytes.
Why Was This Study Done?
People need to know they are HIV positive as soon as possible after they become infected because antiretroviral therapy, which controls but does not cure HIV infection, works best if it is initiated when people still have a relatively high CD4 count. Early diagnosis also reduces the risk of onward HIV transmission. However, 40%–60% of HIV-positive individuals in developed countries are not diagnosed until they have a low CD4 count or an AIDS-defining illness. Reasons for such late presentation include fear of discrimination or stigmatization, limited knowledge about HIV risk factors, testing, and treatment together with missed opportunities to offer an HIV test. Policy makers involved in national and international HIV control programs need detailed information about patterns of late presentation before they can make informed decisions about how to reduce this problem. In this study, therefore, the researchers use data collected by the Collaboration of Observational HIV Epidemiological Research in Europe (COHERE) to analyze trends in late presentation over time across Europe and in different groups of people at risk of HIV infection and to investigate the clinical consequences of late presentation.
What Did the Researchers Do and Find?
The researchers analyzed data collected from 84,524 individuals participating in more than 20 observational studies that were undertaken in 35 European countries and that investigated outcomes among HIV-positive people. Nearly 54% of the participants were late presenters—individuals who had a CD4 count of less than 350 cells/mm3 or an AIDS-defining illness within 6 months of HIV diagnosis. Late presentation was highest among heterosexual males, in Southern European countries, and among people originating in Africa. Overall, late presentation decreased from 57.3% in 2000 to 51.7% in 2010/11. However, whereas late presentation decreased over time among men having sex with men in Central and Northern Europe, for example, it increased over time among female heterosexuals in Southern Europe. Finally, among the 8,000 individuals who developed a new AIDS-defining illness or died during follow-up, compared to non-late presentation, late presentation was associated with an increased incidence of AIDS/death in all regions of Europe during the first and second year after HIV diagnosis (but not in later years); the largest increase in incidence (13-fold) occurred during the first year after diagnosis in Southern Europe.
What Do These Findings Mean?
These findings indicate that, although late presentation with HIV infection has decreased in recent years, it remains an important issue across Europe and in all groups of people at risk of HIV infection. They also show that individuals presenting late have a worse clinical outlook, particularly in the first and second year after diagnosis compared to non-late presenters. Several aspects of the study design may affect the accuracy and usefulness of these findings, however. For example, some of the study participants recorded as late presenters may have been people who were aware of their HIV status but who chose not to seek care for HIV infection, or may have been seen in the health care system prior to HIV diagnosis without being offered an HIV test. Delayed entry into care and late presentation are likely to have different risk factors, a possibility that needs to be studied further. Despite this and other study limitations, these findings nevertheless suggest that HIV testing strategies that encourage early testing in all populations at risk, that ensure timely referrals, and that improve retention in care are required to further reduce the incidence of late presentation with HIV infection in Europe.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/ 10.1371/journal.pmed.1001510.
Information is available from the US National Institute of Allergy and infectious diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS, and summaries of recent research findings on HIV care and treatment
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including detailed information on the stages of HIV infection and on HIV and AIDS in Europe (in English and Spanish)
The HIV in Europe Initiative has information about strategies to improve earlier diagnosis and access to care in Europe
Information about COHERE, which was established in 2005 to conduct epidemiological research on the prognosis and outcome of HIV-infected people from across Europe, is available; more information on the consensus definition of late presentation used in this study is available through the HIV in Europe initiative
Patient stories about living with HIV/AIDS are available through Avert and through the nonprofit website Healthtalkonline
doi:10.1371/journal.pmed.1001510
PMCID: PMC3796947  PMID: 24137103
10.  Proceedings of The 8th Romanian National HIV/AIDS Congress and The 3rd Central European HIV Forum 
Alexiev, Ivailo | Dimitrova, Reneta | Gancheva, Anna | Kostadinova, Asya | Stoycheva, Mariyana | Nikolova, Daniela | Elenkov, Ivaylo | Tilișcan, Cătălin | Predescu, Mioara | Păunescu, Bogdan | Streinu-Cercel, Anca | Săndulescu, Oana | Șchiopu, Claudiu Mihai | Hristache, Mădălina | Brîndușe, Lăcrămioara Aurelia | Streinu-Cercel, Adrian | Todorovic, Marija | Siljic, Marina | Salemovic, Dubravka | Nikolic, Valentina | Pesic-Pavlovic, Ivana | Ranin, Jovan | Jevtovic, Djordje | Stanojevic, Maja | Tudor, Ana Maria | Vlad, Delia | Mărdărescu, Mariana | Petrea, Sorin | Petre, Cristina | Neagu-Drăghicenoiu, Ruxandra | Ungurianu, Rodica | Cibea, Alina | Chirilă, Odette | Anghelina, Cristian | Coserea, Ileana | Krikelli, Pantelia-Amalia | Pavlitina, Eirini | Psichogiou, Mina | Lamnisos, Demetris | Williams, Leslie | Korobchuk, Anya | Skaathun, Britt | Smyrnov, Pavlo | Schneider, John | Sypsa, Vana | Paraskevis, Dimitrios | Hatzakis, Angelos | Friedman, Samuel R. | Nikolopoulos, Georgios K. | Dragović, Gordana | Srdić, Danica | Khawla, Al Musalhi | Soldatović, Ivan | Nikolić, Jelena | Jevtović, Djordje | Nair, Devaki | Temereanca, Aura | Rosca, Adelina | Ene, Luminita | Soontornniyomkij, Benchawa | Diaconu, Carmen | Dita, Claudia | Achim, Cristian | Ruta, Simona | Benea, Șerban | Moroti, Ruxandra | Jipa, Raluca | Manea, Eliza | Stan, Andrada | Benea, Elisabeta | Oțelea, Dan | Hristea, Adriana | Hristea, Adriana | Lăpădat, Irina | Jipa, Raluca | Moroti, Ruxandra | Benea, Șerban | Antonică, Doina | Panait, Irina | Petre, Roxana | Kowalska, Justyna D. | Pietraszkiewicz, Ewa | Grycner, Ewa | Firlag-Burkacka, Ewa | Horban, Andrzej | Vlaicu, Ovidiu | Bănică, Leontina | Paraschiv, Simona | Tudor, Ana-Maria | Moroti, Ruxandra | Oțelea, Dan | Dimitrijević, Bojana | Soldatović, Ivan | Jevtović, Đorđe | Kusić, Jovana | Salemović, Dubravka | Ranin, Jovan | Dragović, Gordana | Florea, Dragoș | Bădicuț, Ioana | Rafila, Alexandru | Camburu, Cornel | Histrea, Adriana | Frățilă, Mihaela | Oțelea, Dan | Gmizic, Ivana | Salemovic, Dubravka | Pesic-Pavlovic, Ivana | Siljic, Marina | Nikolic, Valentina | Djonin-Nenezic, Miljana | Milosevic, Ivana | Brmbolic, Branko | Stanojevic, Maja | Streinu-Cercel, Anca | Săndulescu, Oana | Neguț, Alina Cristina | Predescu, Mioara | Mărdărescu, Alexandra | Săndulescu, Mihai | Streinu-Cercel, Adrian | Pérez, Ana Belen | Chueca, Natalia | Álvarez, Marta | Alados, Juan Carlos | Rivero, Antonio | Vera, Francisco | Delgado, Marcial | Salmeron, Javier | Jiménez, Miguel | Blanco, Maria José | Diago, Moises | Garcia-deltoro, Miguel | Alvarez, Marta | Téllez, Francisco | García, Federico | Tănase, Diana | Manea, Eliza | Bacruban, Rodica | Florea, Dragoș | Oțelea, Dan | Rafila, Alexandru | Mărdărescu, Mariana | Hristea, Adriana | Grgic, Ivana | Planinic, Ana | Santak, Maja | Gorenec, Lana | Lepej, Snjezana Zidovec | Vince, Adriana | Manea, Eliza | Hristea, Adriana | Benea, Șerban | Moroti, Ruxandra | Tănase, Diana | Niculae, Cristian M. | Merisor, Simona | Jipa, Raluca | Paraskevis, Dimitrios | Kostaki, Evangelia | Nikolopoulos, Georgios K. | Sypsa, Vana | Psichogiou, Mina | Paraskeva, Dimitra | Skoutelis, Athanassios | Malliori, Meni | Friedman, Samuel R. | Hatzakis, Angelos | Hackiewicz, Malgorzata | Zabek, Piotr | Firlag-Burkacka, Ewa | Horban, Andrzej | Kowalska, Justyna Dominika | Lunar, Maja M. | Mlakar, Jana | Poljak, Mario | Bănică, Leontina | Martin, Eliza | Gheorghiță, Valeriu | Petrescu, Andrei | Oțelea, Dan | Popescu, Costin-Ioan | Paraschiv, Simona | Neaga, Emil | Ovidiu, Vlaicu | Juncu, Andrei | Bănică, Leontina | Paraschiv, Simona | Oțelea, Dan | Popescu, Costin-Ioan | Luca, Adrian | Lazăr, Florin | Luca, Anca Elena | Ene, Luminița | Achim, Cristian | Gingăraş, Cosmina | Anton, Ștefan Adrian | Rădoi, Roxana | Tetradov, Simona | Țârdei, Grațiela | Nica, Maria | Capşa, Razvan Alexandru | Achim, Cristian L. | Oprea, Cristiana | Ene, Luminița | Szymańska, Bogna | Gawron, Natalia | Pluta, Agnieszka | Łojek, Emilia | Firląg-Burkacka, Ewa | Horban, Andrzej | Bornstein, Robert | Burcoș, Olivia | Erscoiu, Simona Manuela | Cojanu, Filofteia Bănicioiu | Toderan, Andreea | Nica, Maria | Popa, Ionuț Cristian | Ceaușu, Emanoil | Calistru, Petre Iacob | Arbune, Manuela | Alexandrache, Mirela | Arbune, Anca-Adriana | Voinescu, Doina-Carina | Diaconu, Ioan-Alexandru | Stratan, Laurențiu | Aramă, Victoria | Nichita, Luciana | Diaconu, Alexandra | Negru, Anca | Orfanu, Alina | Leuștean, Anca | Ion, Daniela Adriana | Ianache, Irina | Oprea, Cristiana | Leuștean, Anca | Popescu, Cristina | Orfanu, Alina | Negru, Anca | Catana, Remulus | Murariu, Cristina | Diaconu, Ioan-Alexandru | Rădulescu, Mihaela | Tilișcan, Cătălin | Aramă, Victoria | Marincu, Iosif | Poptelecan, Patricia | Bică, Valeria | Lazăr, Florin | Tirnea, Livius | Ianache, Irina | Rădoi, Roxana | Nica, Manuela | Țârdei, Grațiela | Ene, Luminița | Ceaușu, Emanoil | Calistru, Petre | Oprea, Cristiana | Osoianu, Iurie | Halacu, Ala | Stoian, Andreea Cristina | Dumitrescu, Florentina | Diaconescu, Iulian | Cupșa, Augustin | Giubelan, Lucian | Ionescu, Loredana | Niculescu, Irina | Chiriac, Carmen | Șincu, Nina | Kezdi, Iringo Zaharia | Georgescu, Anca | Țilea, Brândușa | Girbovan, Cristina | Incze, Andrea | Fodor, Andrea | Cibea, Alina | Mărdărescu, Mariana | Petre, Cristina | Drăghicenoiu, Ruxandra | Ungurianu, Rodica | Tudor, Ana Maria | Vlad, Delia | Matei, Carina | Dumea, Elena | Petcu, Lucian Cristian | Cambrea, Simona Claudia | Dumitrescu, Florentina | Cupsa, Augustin | Stoian, Andreea Cristina | Giubelan, Lucian | Niculescu, Irina | Diaconescu, Iulian | Hurezeanu, Dan | Dragonu, Livia | Cotulbea, Mioara | Erscoiu, Simona Manuela | Popa, Ionuț Cristian | Stroie, Denisa | Ionescu, Petronela | Duță, Nedeea | Dobrea, Camelia | Voican, Irina | Ceaușu, Emanoil | Calistru, Petre Iacob | Lazăr, Florin | Giubelan, Lucian | Cupșa, Augustin | Diaconescu, Iulian | Dumitrescu, Florentina | Hurezeanu, Dan | Dragonu, Livia | Niculescu, Irina | Stoian, Andreea Cristina | Obretin, Oana | Stănescu, Mariana | Jianu, Mihai | Gorenec, Lana | Lepej, Snjezana Zidovec | Grgic, Ivana | Planinic, Ana | Bes, Janja Iscic | Vince, Adriana | Begovac, Josip | Horga, Luminița Elena | Itu, Corina | Horga, Luminița Elena | David-Aldea, Laura Augusta | Ciorogar, Anca | Jianu, Cristian | Lupșe, Mihaela | Caramangiu, Iuliana | Roșca, Ovidiu | Cialma, Monica | Ardeleanu, Andreea | Marincu, Iosif | Jipa, Raluca | Manea, Eliza | Benea, Șerban | Lăpădat, Irina | Irimescu, Nicoleta | Panait, Irina | Niculae, Cristian | Hristea, Adriana | Kusic, Jovana | Jevtovic, Djordje | Salemovic, Dubravka | Ranin, Jovan | Dimitrijevic, Bozana | Dragovic, Gordana | Aldea-David, Laura-Augusta | Manciuc, Carmen | Nicolau, Cristina | Prisăcariu, Liviu | Largu, Alexandra | Mărdărescu, Mariana | Streinu-Cercel, Adrian | Petre, Cristina | Iancu, Marieta | Vintilă, Sanda | Vitelaru, Daniela | Ionel, Iosif | Șchiopu, Claudiu Mihai | Mărdărescu, Alexandra-Henriette | Micsanschi, Pavel | Holban, Tiberiu | Bîstrițchi, Ina | Pârțână, Lucia | Nagîț, Angela | Popovici, Svetlana | Talmaci, Maria | Cucerova, Irina | Mitrescu, Sorina Georgiana | Mihalcea, Dana | Caramangiu, Iulia | Roșca, Ovidiu | Maricu, Iosif | Negru, Anca | Munteanu, Daniela | Aramă, Victoria | Mihăilescu, Raluca | Diaconu, Ioan | Catana, Remulus | Popescu, Cristina | Orfanu, Alina | Leuștean, Anca | Rădulescu, Mihaela | Tilișcan, Cătălin | Năstase, Raluca | Molagic, Violeta | Duport, Irina | Dragomirescu, Cristina | Aramă, Ștefan Sorin | Negruț, Nicoleta M. | Niță, Violeta Elena | Munteanu, Daniela Ioana | Mihăilescu, Raluca | Diaconu, Ioan | Negru, Anca | Popescu, Cristina | Aramă, Victoria | Orfanu, Alina | Popescu, Cristina | Leuștean, Anca | Negru, Anca | Catana, Remulus | Diaconu, Ioan | Tilișcan, Cătălin | Aramă, Victoria | Aramă, Sorin Ștefan | Pavlovia, Ivana Pesic | Salemovic, Dubravka | Ranin, Jovan | Jevtovic, Djordje | Roșca, Ovidiu | Ardeleanu, Andreea | Caramangiu, Iulia | Desaga, Daniela | Bică, Valerica | Mitrescu, Sorina | Marincu, Iosif | Siljic, Marina | Salemovic, Dubravka | Nikolic, Valentina | Jevtovic, Djordje | Pesic-Pavlovic, Ivana | Ranin, Jovan | Todorovic, Marija | Stanojevic, Maja | Șincu, Nina-Ioana | Georgescu, Anca | Țilea, Brândușa | Kezdi, Iringo Zaharia | Incze, Andrea | Gârbovan, Cristina | Chiriac, Carmen Lucia | Luca, Anca Elena | Lazăr, Florin | Luca, Adrian | Ene, Luminița | Rădoi, Roxana | Talnariu, Adina | Suciu, Silvia | Achim, Cristian | Iacob, Diana Gabriela | Florea, Dragoș | Iacob, Simona | Arbune, Manuela | Drăgănescu, Miruna | Iancu, Alina | Moroti, Ruxandra | Niculae, Cristian M. | Merisor, Simona | Manea, Eliza | Benea, Serban | Stan, Andrada | Hrisca, Raluca | Jipa, Raluca | Tanase, Diana | Hristea, Adriana | Grgic, Ivana | Planinic, Ana | Gorenec, Lana | Lepej, Snjezana Zidovec | Vince, Adriana
BMC Infectious Diseases  2016;16(Suppl 3):290.
O1 HIV-1 diversity in Bulgaria (current molecular epidemiological picture)
Ivailo Alexiev, Reneta Dimitrova, Anna Gancheva, Asya Kostadinova, Mariyana Stoycheva, Daniela Nikolova, Ivaylo Elenkov
O2 Knowledge, attitudes and practices of the general population on HIV/AIDS, hepatitis B and C in Romania
Cătălin Tilișcan, Mioara Predescu, Bogdan Păunescu, Anca Streinu-Cercel, Oana Săndulescu, Claudiu Mihai Șchiopu, Mădălina Hristache, Lăcrămioara Aurelia Brîndușe, Adrian Streinu-Cercel
O3 The prevalence of human leukocyte antigen-B*57:01 allele carriers and CXCR4 tropism among newly diagnosed HIV infected patients in Serbia
Marija Todorovic, Marina Siljic, Dubravka Salemovic, Valentina Nikolic, Ivana Pesic-Pavlovic, Jovan Ranin, Djordje Jevtovic, Maja Stanojevic
O4 HIV transmission among stable serodiscordant couples from the former Pediatric Cohort follow up in the National Institute of Infectious Diseases
Ana Maria Tudor, Delia Vlad, Mariana Mărdărescu, Sorin Petrea, Cristina Petre, Ruxandra Neagu-Drăghicenoiu, Rodica Ungurianu, Alina Cibea, Odette Chirilă, Cristian Anghelina, Ileana Coserea
O5 Unemployment is associated with syringe sharing among people who inject drugs in Greece
Pantelia-Amalia Krikelli, Eirini Pavlitina, Mina Psichogiou, Demetris Lamnisos, Leslie Williams, Anya Korobchuk, Britt Skaathun, Pavlo Smyrnov, John Schneider, Vana Sypsa, Dimitrios Paraskevis, Angelos Hatzakis, Samuel R. Friedman, Georgios K. Nikolopoulos
O6 Correlation of adipocytokine levels in different types of lipodystrophy in HIV/AIDS patients
Gordana Dragović, Danica Srdić, Al Musalhi Khawla, Ivan Soldatović, Jelena Nikolić, Djordje Jevtović, Devaki Nair
O7 IP10 – a possible biomarker for the progression of HIV infection
Aura Temereanca, Adelina Rosca, Luminita Ene, Benchawa Soontornniyomkij, Carmen Diaconu, Claudia Dita, Cristian Achim, Simona Ruta
O8 A permanent challenge: persistent low viremia in HIV positive patients on ART
Șerban Benea, Ruxandra Moroti, Raluca Jipa, Eliza Manea, Andrada Stan, Elisabeta Benea, Dan Oțelea, Adriana Hristea
O9 Infections in IDUs according to their HIV status
Adriana Hristea, Irina Lăpădat, Raluca Jipa, Ruxandra Moroti, Șerban Benea, Doina Antonică, Irina Panait, Roxana Petre
O10 Trends in combined antiretroviral therapy used in methadone program integrated with HIV care - 20 years of experience
Justyna D. Kowalska, Ewa Pietraszkiewicz, Ewa Grycner, Ewa Firlag-Burkacka, Andrzej Horban
O11 Extracellular cyclophilin A – inflammatory mediator in HIV infected patients
Ovidiu Vlaicu, Leontina Bănică, Simona Paraschiv, Ana-Maria Tudor, Ruxandra Moroti, Dan Oțelea
O12 High cardiovascular disease risk in Serbian population, an issue of concern
Bojana Dimitrijević, Ivan Soldatović, Đorđe Jevtović, Jovana Kusić, Dubravka Salemović, Jovan Ranin, Gordana Dragović
O13 Genotypic rifampicin resistance in HIV/ tuberculosis coinfected patients from a tertiary level infectious diseases hospital
Dragoș Florea, Ioana Bădicuț, Alexandru Rafila, Cornel Camburu, Adriana Histrea, Mihaela Frățilă, Dan Oțelea
O14 Occurrence of residual HCV RNA in liver and peripheral blood mononuclear cells among patients with chronic hepatitis C infection and/or HCV/HIV coinfection after IFN-based therapy
Ivana Gmizic, Dubravka Salemovic, Ivana Pesic-Pavlovic, Marina Siljic, Valentina Nikolic, Miljana Djonin-Nenezic, Ivana Milosevic, Branko Brmbolic, Maja Stanojevic
O15 Romanian nationwide screening for infection with HIV and hepatitis B and C viruses
Anca Streinu-Cercel, Oana Săndulescu, Alina Cristina Neguț, Mioara Predescu, Alexandra Mărdărescu, Mihai Săndulescu, Adrian Streinu-Cercel
O16 Treatment emergent variants to combined direct antiviral agents therapy against hepatitis C virus
Ana Belen Pérez, Natalia Chueca, Marta Álvarez, Juan Carlos Alados, Antonio Rivero, Francisco Vera, Marcial Delgado, Javier Salmeron, Miguel Jiménez, Maria José Blanco, Moises Diago, Miguel Garcia-deltoro, Marta Alvarez, Francisco Téllez, Federico García
O17 Clinical and epidemiological aspects in tuberculosis/HIV coinfected patients
Diana Tănase, Eliza Manea, Rodica Bacruban, Dragoș Florea, Dan Oțelea, Alexandru Rafila, Mariana Mărdărescu, Adriana Hristea
O18 Resistance to NS3 protease inhibitors in persons with chronic hepatitis C infected with hepatitis C virus subtype 1a from Croatia
Ivana Grgic, Ana Planinic, Maja Santak, Lana Gorenec, Snjezana Zidovec Lepej, Adriana Vince
O19 Analysis of a simplified diagnostic score for tuberculous meningitis in HIV-infected adults with meningitis
Eliza Manea, Adriana Hristea, Șerban Benea, Ruxandra Moroti, Diana Tănase, Cristian M. Niculae, Simona Merisor, Raluca Jipa
O20 Molecular tracing of the origin of HIV-1 infection among persons who inject drugs in Athens: a phyloethnic study
Dimitrios Paraskevis, Evangelia Kostaki, Georgios K. Nikolopoulos, Vana Sypsa, Mina Psichogiou, Dimitra Paraskeva, Athanassios Skoutelis, Meni Malliori, Samuel R. Friedman, Angelos Hatzakis
O21 The dynamics of virological response to HIV-1 infection and antiretroviral therapy initiation in patients with and without HLA-B*5701 Allele
Malgorzata Hackiewicz, Piotr Zabek, Ewa Firlag-Burkacka, Andrzej Horban, Justyna Dominika Kowalska
O22 Increase in the numbers of non-B subtypes and potential recombinant forms circulating among Slovenian MSM in the recent years
Maja M. Lunar, Jana Mlakar, Mario Poljak
O23 Genotyping intrahost polymorphisms in hepatitis C virus E2 protein associated with resistance to antibody neutralization
Leontina Bănică, Eliza Martin, Valeriu Gheorghiță, Andrei Petrescu, Dan Oțelea, Costin-Ioan Popescu, Simona Paraschiv
O24 Genotyping of HCV NS3 protease inhibitors resistance and phenotyping of rare double resistance mutations in HCV cell culture system
Emil Neaga, Vlaicu Ovidiu, Andrei Juncu, Leontina Bănică, Simona Paraschiv, Dan Oțelea, Costin-Ioan Popescu
O25 Employment status controls the relationship between neurocognitive impairment and depression in a cohort of young HIV-infected adults since childhood
Adrian Luca, Florin Lazăr, Anca Elena Luca, Luminița Ene, Cristian Achim
O26 Predictors of survival in parenterally-infected HIV positive children and youth diagnosed with progressive multifocal leukoencephalopathy
Cosmina Gingăraş, Ștefan Adrian Anton, Roxana Rădoi, Simona Tetradov, Grațiela Țârdei, Maria Nica, Razvan Alexandru Capşa, Cristian L. Achim, Cristiana Oprea, Luminița Ene
O27 Neurocognitive and brain functioning in HIV-infected young MSM treated with cART
Bogna Szymańska, Natalia Gawron, Agnieszka Pluta, Emilia Łojek, Ewa Firląg – Burkacka, Andrzej Horban, Robert Bornstein, et HARMONIA3 Study Group
O28 Clinical value of RT-PCR detection of Toxoplasma gondii DNA in cerebrospinal fluid
Olivia Burcoș, Simona Manuela Erscoiu, Filofteia Bănicioiu Cojanu, Andreea Toderan, Maria Nica, Ionuț Cristian Popa, Emanoil Ceaușu, Petre Iacob Calistru
O29 Characteristics of sleep disorders in Romanian adults infected with human immunodeficiency virus
Manuela Arbune, Mirela Alexandrache, Anca-Adriana Arbune, Doina-Carina Voinescu
O30 Diagnosing neuroHIV: the rift between clinicians and pathologists
Ioan-Alexandru Diaconu, Laurențiu Stratan, Victoria Aramă, Luciana Nichita, Alexandra Diaconu, Anca Negru, Alina Orfanu, Anca Leuștean, Daniela Adriana Ion
O31 A challenging neurological complication in a HIV-infected young woman with multiple opportunistic infections
Irina Ianache, Cristiana Oprea
O32 Brain abscess with uncertain etiology in a late-presenter HIV infected patient
Anca Leuștean, Cristina Popescu, Alina Orfanu, Anca Negru, Remulus Catana, Cristina Murariu, Ioan-Alexandru Diaconu, Mihaela Rădulescu, Cătălin Tilișcan, Victoria Aramă
O33 Cerebral toxoplasmosis and left crural monoparesis with fatal evolution in a noncompliant patient with AIDS C3
Iosif Marincu, Patricia Poptelecan, Valeria Bică, Florin Lazăr, Livius Tirnea
O34 Opportunistic infections still a problem in HIV-infected patients in cART era: a Romanian single center experience
Irina Ianache, Roxana Rădoi, Manuela Nica, Grațiela Țârdei, Luminița Ene, Emanoil Ceaușu, Petre Calistru, Cristiana Oprea
P1: Epidemiological aspects of co-infection of HIV/TB in Moldova
Iurie Osoianu, Ala Halacu
P2 Perinatal exposure at HIV infection in Oltenia region
Andreea Cristina Stoian, Florentina Dumitrescu, Iulian Diaconescu, Augustin Cupșa, Lucian Giubelan, Loredana Ionescu, Irina Niculescu
P3 Women living with HIV in Mureș county
Carmen Chiriac, Nina Șincu, Iringo Zaharia Kezdi, Anca Georgescu, Brândușa Țilea, Cristina Girbovan, Andrea Incze, Andrea Fodor
P4 Late diagnosis of HIV infection in children - a challenge for Romania
Alina Cibea, Mariana Mărdărescu, Cristina Petre, Ruxandra Drăghicenoiu, Rodica Ungurianu, Ana Maria Tudor, Delia Vlad, Carina Matei
P5 Cirrhosis Assessment in Patients Co-infected HIV-Hepatitis B Virus
Elena Dumea, Lucian Cristian Petcu, Simona Claudia Cambrea
P6 HIV late presenters in Craiova Regional Center, Romania
Florentina Dumitrescu, Augustin Cupsa, Andreea Cristina Stoian, Lucian Giubelan, Irina Niculescu, Iulian Diaconescu, Dan Hurezeanu, Livia Dragonu, Mioara Cotulbea
P7 Some aspects of malignancies in patients HIV / AIDS
Simona Manuela Erscoiu, Ionuț Cristian Popa, Denisa Stroie, Petronela Ionescu, Nedeea Duță, Camelia Dobrea, Irina Voican, Emanoil Ceaușu, Petre Iacob Calistru
P8 Factors associated with resilience among people living with HIV in Romania
Florin Lazăr
P9 Fever in HIV-infected patients: a thorny problem to be solved by the clinicians
Lucian Giubelan, Augustin Cupșa, Iulian Diaconescu, Florentina Dumitrescu, Dan Hurezeanu, Livia Dragonu, Irina Niculescu, Andreea Cristina Stoian, Oana Obretin, Mariana Stănescu, Mihai Jianu
P10 Th1, Th2, Th9, Th17 and Th22 cytokines in acute and chronic HIV-1 infection
Lana Gorenec, Snjezana Zidovec Lepej, Ivana Grgic, Ana Planinic, Janja Iscic Bes, Adriana Vince, Josip Begovac
P11 Dyslipidemia in HIV-infected patients treated with protease inhibitors – case report
Luminița Elena Horga
P12 Why use less treatment for the metabolic abnormalities in HIV patients-too many drugs?
Corina Itu, Luminița Elena Horga, Laura Augusta David-Aldea, Anca Ciorogar, Cristian Jianu, Mihaela Lupșe
P13 Sacral Herpes Zoster, with hyperalgesic form, in a patient with C3 stage HIV infection
Iuliana Caramangiu, Ovidiu Roșca, Monica Cialma, Andreea Ardeleanu, Iosif Marincu
P14 Factors associated with in-hospital mortality in tuberculous and cryptococcal meningitis
Raluca Jipa, Eliza Manea, Șerban Benea, Irina Lăpădat, Nicoleta Irimescu, Irina Panait, Cristian Niculae, Adriana Hristea
P15 Lipodystrophy: still present adverse event in resource-limited settings
Jovana Kusic, Djordje Jevtovic, Dubravka Salemovic, Jovan Ranin, Bozana Dimitrijevic, Gordana Dragovic
P16 TB and HIV coinfected patient, an emergent challenge - case report
Laura-Augusta Aldea-David
P17 Efficacy of prophylactic antiretroviral treatment in new-born infants from HIV-positive mothers in 2012-2014, for the North-Eastern part of Romania
Carmen Manciuc, Cristina Nicolau, Liviu Prisăcariu, Alexandra Largu
P18 Surveillance of mother to child transmission of HIV in Romania – 31 December 2015
Mariana Mărdărescu, Adrian Streinu-Cercel, Cristina Petre, Marieta Iancu, Sanda Vintilă, Daniela Vitelaru, Iosif Ionel, Claudiu Mihai Șchiopu, Alexandra-Henriette Mărdărescu
P19 The antiretroviral therapy failure and the need to select the effective treatment in the Republic of Moldova
Pavel Micsanschi, Tiberiu Holban, Ina Bîstrițchi, Lucia Pârțână, Angela Nagîț, Svetlana Popovici, Maria Talmaci, Irina Cucerova
P20 Disseminated cryptococcosis in a patient with C3 HIV stage and multiresistant to antiretroviral therapy with lethal evolution
Sorina Georgiana Mitrescu, Dana Mihalcea, Iulia Caramangiu, Ovidiu Roșca, Iosif Maricu
P21 Aspects of tuberculosis infection in HIV-positive patients from Romania – our experience
Anca Negru, Daniela Munteanu, Victoria Aramă, Raluca Mihăilescu, Ioan Diaconu, Remulus Catana, Cristina Popescu, Alina Orfanu, Anca Leuștean, Mihaela Rădulescu, Cătălin Tilișcan, Raluca Năstase, Violeta Molagic, Irina Duport, Cristina Dragomirescu, Ștefan Sorin Aramă
P22 Dyslipidemia in HIV-infected patients
Nicoleta M Negruț
P23 Challenges in the management of an HIV seropositive patient with psoriasis undergoing immunomodulator therapy
Violeta Elena Niță, Daniela Ioana Munteanu, Raluca Mihăilescu, Ioan Diaconu, Anca Negru, Cristina Popescu, Victoria Aramă
P24 Acute peritonitis as a sign of IRIS in an HIV-infected patient with MAC latent infection
Alina Orfanu, Cristina Popescu, Anca Leuștean, Anca Negru, Remulus Catana, Ioan Diaconu, Cătălin Tilișcan, Victoria Aramă, Sorin Ștefan Aramă
P25 The virologic outcome of the treatment of chronic hepatitis B among HIV co-infected patients on HAART
Ivana Pesic Pavlovia, Dubravka Salemovic, Jovan Ranin, Djordje Jevtovic
P26 A case of HIV encephalopathy with aphasia, agnosia, apraxia and right homonymous hemianopsia
Ovidiu Roșca, Andreea Ardeleanu, Iulia Caramangiu, Daniela Desaga, Valerica Bică, Sorina Mitrescu, Iosif Marincu
P27 Molecular footprints on human immunodeficiency virus -1 genome and association with phylogenetic clustering among subtype B infected patients in Serbia
Marina Siljic, Dubravka Salemovic, Valentina Nikolic, Djordje Jevtovic, Ivana Pesic-Pavlovic, Jovan Ranin, Marija Todorovic , Maja Stanojevic
P28 Neurosyphilis and human immunodeficiency virus infection: double challenge
Nina-Ioana Șincu, Anca Georgescu, Brândușa Țilea, Iringo Zaharia Kezdi, Andrea Incze, Cristina Gârbovan, Carmen Lucia Chiriac
P29 Differences between HIV-infected adults since childhood and non HIV-infected persons on managing everyday life
Anca Elena Luca, Florin Lazăr, Adrian Luca, Luminița Ene, Roxana Rădoi, Adina Talnariu, Silvia Suciu, Cristian Achim
P30 Molecular detection of Bartonella quintana in a HIV immunodepressed patient with fever and isolated lymphadenopathy - Case report
Diana Gabriela Iacob, Dragoș Florea, Simona Iacob
P31 Present epidemiological characteristics of HIV/AIDS newly diagnosed cases in South-Eastern Romania
Manuela Arbune, Miruna Drăgănescu, Alina Iancu
P32 The gender’s preferences among opportunists?
Ruxandra Moroti, Cristian M Niculae, Simona Merisor, Eliza Manea, Serban Benea, Andrada Stan, Raluca Hrisca, Raluca Jipa, Diana Tanase, Adriana Hristea
P33 Polymorphism of interleukin-28B gene in persons with chronic hepatitis C from Croatia
Ivana Grgic, Ana Planinic, Lana Gorenec, Snjezana Zidovec Lepej, Adriana Vince
doi:10.1186/s12879-016-1480-8
PMCID: PMC4928154  PMID: 27356504
11.  Reassessment of HIV-1 Acute Phase Infectivity: Accounting for Heterogeneity and Study Design with Simulated Cohorts 
PLoS Medicine  2015;12(3):e1001801.
Background
The infectivity of the HIV-1 acute phase has been directly measured only once, from a retrospectively identified cohort of serodiscordant heterosexual couples in Rakai, Uganda. Analyses of this cohort underlie the widespread view that the acute phase is highly infectious, even more so than would be predicted from its elevated viral load, and that transmission occurring shortly after infection may therefore compromise interventions that rely on diagnosis and treatment, such as antiretroviral treatment as prevention (TasP). Here, we re-estimate the duration and relative infectivity of the acute phase, while accounting for several possible sources of bias in published estimates, including the retrospective cohort exclusion criteria and unmeasured heterogeneity in risk.
Methods and Findings
We estimated acute phase infectivity using two approaches. First, we combined viral load trajectories and viral load-infectivity relationships to estimate infectivity trajectories over the course of infection, under the assumption that elevated acute phase infectivity is caused by elevated viral load alone. Second, we estimated the relative hazard of transmission during the acute phase versus the chronic phase (RHacute) and the acute phase duration (dacute) by fitting a couples transmission model to the Rakai retrospective cohort using approximate Bayesian computation. Our model fit the data well and accounted for characteristics overlooked by previous analyses, including individual heterogeneity in infectiousness and susceptibility and the retrospective cohort's exclusion of couples that were recorded as serodiscordant only once before being censored by loss to follow-up, couple dissolution, or study termination. Finally, we replicated two highly cited analyses of the Rakai data on simulated data to identify biases underlying the discrepancies between previous estimates and our own.
From the Rakai data, we estimated RHacute = 5.3 (95% credibility interval [95% CrI]: 0.79–57) and dacute = 1.7 mo (95% CrI: 0.55–6.8). The wide credibility intervals reflect an inability to distinguish a long, mildly infectious acute phase from a short, highly infectious acute phase, given the 10-mo Rakai observation intervals. The total additional risk, measured as excess hazard-months attributable to the acute phase (EHMacute) can be estimated more precisely: EHMacute = (RHacute - 1) × dacute, and should be interpreted with respect to the 120 hazard-months generated by a constant untreated chronic phase infectivity over 10 y of infection. From the Rakai data, we estimated that EHMacute = 8.4 (95% CrI: -0.27 to 64). This estimate is considerably lower than previously published estimates, and consistent with our independent estimate from viral load trajectories, 5.6 (95% confidence interval: 3.3–9.1). We found that previous overestimates likely stemmed from failure to account for risk heterogeneity and bias resulting from the retrospective cohort study design.
Our results reflect the interaction between the retrospective cohort exclusion criteria and high (47%) rates of censorship amongst incident serodiscordant couples in the Rakai study due to loss to follow-up, couple dissolution, or study termination. We estimated excess physiological infectivity during the acute phase from couples data, but not the proportion of transmission attributable to the acute phase, which would require data on the broader population's sexual network structure.
Conclusions
Previous EHMacute estimates relying on the Rakai retrospective cohort data range from 31 to 141. Our results indicate that these are substantial overestimates of HIV-1 acute phase infectivity, biased by unmodeled heterogeneity in transmission rates between couples and by inconsistent censoring. Elevated acute phase infectivity is therefore less likely to undermine TasP interventions than previously thought. Heterogeneity in infectiousness and susceptibility may still play an important role in intervention success and deserves attention in future analyses
Using simulated cohorts that account for previously unmeasured bias, Steve Bellan and colleagues provide new estimates of the duration and relative infectivity of the HIV-1 acute phase based on data from the retrospective cohort of serodiscordant couples in Rakai, Uganda.
Editors' Summary
Background.
About 35 million people are currently infected with HIV, the virus that causes AIDS, and more than 2 million people become newly infected with the virus every year, usually through having unprotected sex with an infected partner. Most people do not become ill immediately after infection, although some people develop a short flu-like illness. However, during this acute phase of infection, the amount of virus in the blood—the viral load—rises rapidly and peaks, before decreasing to a relatively stable lower level during the chronic phase of HIV infection. Chronic HIV infection, which may last for more than ten years, also has no major symptoms, but HIV slowly destroys immune system cells throughout this phase. Eventually, the immune system can no longer fight off infections by other disease-causing organisms, and HIV-positive people then develop one or more AIDS-defining conditions, including unusual infections and specific types of cancer; the HIV load also rises again during late phase infection.
Why Was This Study Done?
Antiretroviral therapy (ART) can control, but not cure, HIV infection. By decreasing the viral load, ART not only improves the health of HIV-positive individuals, but also reduces their infectiousness. Consequently, experts believe that scaling up ART could substantially reduce the rate of new HIV infections. But the successful implementation of “treatment as prevention” faces several challenges. Notably, HIV testing and treatment programs need to be widely available, and people who are HIV-positive need to adhere to ART. Another major challenge that faces treatment as prevention is that HIV transmission that occurs during the acute phase of infection is likely to evade the intervention, and it is widely accepted that HIV-positive individuals are highly infectious during this phase of infection. However, acute phase infectivity has been directly measured only once: in a retrospectively identified group of serodiscordant heterosexual couples (couples in which only one partner was HIV-positive) in Rakai, Uganda. The authors of the current study found that existing estimates of acute phase infectivity failed to take account of important aspects of the Rakai study design or of heterogeneity (variability) in infectiousness or susceptibility among the study participants. Here, the researchers use mathematical modeling to compare simulated cohorts with the Rakai data to provide new estimates of the duration and relative infectivity of the acute phase that take into account study design and heterogeneity.
What Did the Researchers Do and Find?
The researchers first used viral load trajectories and viral load–infectivity relationships to estimate infectivity trajectories over the course of infection. Using this approach, they estimated that the total additional risk attributable to the acute phase expressed as EHMacute (excess hazard-months attributable to the acute phase of infection above the hazard generated by constant untreated chronic phase infectivity) was 5.6, which is considerably lower than previous estimates (which range from 31 to 141). Next, by fitting a mathematical model designed to simulate HIV infection and transmission within couples to the Rakai data, they estimated that the relative hazard of transmission during the acute phase versus the chronic phase (RHacute) was 5.3, that the acute phase duration (dacute) was 1.7 months, and that EHMacute was 8.4. Finally, by replicating two highly cited analyses of the Rakai data on simulated data, the researchers show that the previous overestimates of acute phase infectivity likely stemmed from a failure to account for risk heterogeneity among study participants (some participants were more likely to transmit HIV or contract HIV than others because of underlying biological or behavioral differences in their infectiousness or susceptibility, respectively) and from bias arising from the retrospective cohort design of the Rakai study (serodiscordant couples who were lost to follow-up were excluded).
What Do These Findings Mean?
In common with previous estimates of acute phase infectivity, the accuracy of these findings depends on the many assumptions made by the researchers in developing their mathematical models and on the quality of the data fed into these models. Nevertheless, these findings suggest that previous estimates of the infectivity of acute phase HIV infection are substantial overestimates. Thus, the researchers suggest, elevated infectiousness early in infection alone is unlikely to undermine treatment as prevention campaigns, and the population-level benefits of treatment as prevention may be larger than predicted from earlier estimates. These revised estimates—and the impact of heterogeneity of HIV infectiousness and susceptibility to infection on HIV transmission within populations revealed by this analysis—should now be considered when designing population-scale interventions and when communicating individual-level risk of HIV transmission and infection in clinical and community settings.
Additional Information.
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001801.
This study is further discussed in a PLOS Medicine Perspective by Laith J. Abu-Raddad
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS, information about transmission and prevention, summaries of recent research findings on HIV care and treatment, and personal stories about living with AIDS/HIV
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including detailed information on the stages of HIV infection and on treatment as prevention, and personal stories about living with HIV/AIDS
The World Health Organization provides information on all aspects of HIV/AIDS (in several languages), including its guidelines on the use of ART for treating and preventing HIV infection
The UNAIDS World AIDS Day Report 2014 provides up-to-date information about the AIDS epidemic and efforts to halt it
The PLOS Medicine Collection “Investigating the Impact of Treatment on New HIV Infections” provides more information about HIV treatment as prevention
doi:10.1371/journal.pmed.1001801
PMCID: PMC4363602  PMID: 25781323
12.  Antiretroviral Pre-exposure Prophylaxis Prevents Vaginal Transmission of HIV-1 in Humanized BLT Mice 
PLoS Medicine  2008;5(1):e16.
Background
Worldwide, vaginal transmission now accounts for more than half of newly acquired HIV-1 infections. Despite the urgency to develop and implement novel approaches capable of preventing HIV transmission, this process has been hindered by the lack of adequate small animal models for preclinical efficacy and safety testing. Given the importance of this route of transmission, we investigated the susceptibility of humanized mice to intravaginal HIV-1 infection.
Methods and Findings
We show that the female reproductive tract of humanized bone marrow–liver–thymus (BLT) mice is reconstituted with human CD4+ T and other relevant human cells, rendering these humanized mice susceptible to intravaginal infection by HIV-1. Effects of HIV-1 infection include CD4+ T cell depletion in gut-associated lymphoid tissue (GALT) that closely mimics what is observed in HIV-1–infected humans. We also show that pre-exposure prophylaxis with antiretroviral drugs is a highly effective method for preventing vaginal HIV-1 transmission. Whereas 88% (7/8) of BLT mice inoculated vaginally with HIV-1 became infected, none of the animals (0/5) given pre-exposure prophylaxis of emtricitabine (FTC)/tenofovir disoproxil fumarate (TDF) showed evidence of infection (Chi square = 7.5, df = 1, p = 0.006).
Conclusions
The fact that humanized BLT mice are susceptible to intravaginal infection makes this system an excellent candidate for preclinical evaluation of both microbicides and pre-exposure prophylactic regimens. The utility of humanized mice to study intravaginal HIV-1 transmission is particularly highlighted by the demonstration that pre-exposure prophylaxis can prevent intravaginal HIV-1 transmission in the BLT mouse model.
J. Victor Garcia and colleagues show that mice with immune systems reconstituted from human bone marrow, liver, and thymus transplants provide a model for prevention of intravaginal HIV infection.
Editors' Summary
Background.
Since the first cases of acquired immunodeficiency syndrome (AIDS) in 1981, the AIDS epidemic has spread rapidly. About 33 million people are now infected with the human immunodeficiency virus (HIV), the cause of AIDS. More than half of newly acquired infections now occur in women, mostly through unprotected vaginal sex with an infected male partner. Women are biologically more susceptible than men to HIV infection during vaginal intercourse and often cannot persuade their partner to use a condom. Consequently, alternative strategies that prevent intravaginal transmission of HIV (infection through the vagina) are urgently needed, particularly strategies that women can use without their partner's agreement. A vaccine would be ideal but it could be many years before an effective HIV vaccine is available so researchers are investigating other preventative strategies such as the use of microbicides—compounds that protect against HIV when applied inside the vagina—and pre-exposure treatment (prophylaxis) with antiretroviral drugs.
Why Was This Study Done?
Before any new strategy to prevent intravaginal HIV transmission is tried by women, it has to be tested in animals. Currently, this can only be done in macaques, an expensive option. In this study, the researchers have investigated whether “humanized BLT” mice could be used instead. When HIV enters the human body during vaginal intercourse, it sticks to dendritic cells (a type of immune system cell) in the vaginal lining. These cells carry the virus to the body's lymphoid tissues (collections of immune cells), where it infects and kills CD4+ T cells (another type of immune cell). Dendritic cells and CD4+ T cells have molecules on their surface that HIV recognizes. Mice are not normally susceptible to infection with HIV because their immune system cells lack these molecules. Humanized BLT mice have a nearly human immune system—BLT stands for bone marrow, liver, thymus. They are produced by implanting pieces of human fetal liver and thymus (the organ where T cells learn to recognize foreign invaders) under the kidney capsule of immunodeficient mice (animals born without an immune system) and then transplanting human hematopoietic stem cells (the source of the major immune system cells) into the mice.
What Did the Researchers Do and Find?
When the researchers examined the female reproductive tract of humanized BLT mice for human immune system cells, they found CD4+ T cells, dendritic cells and macrophages, all of which are involved in HIV infection. Furthermore, half of the blood cells of the BLT mice were human. Most of the BLT mice, the researchers report, were susceptible to intravaginal HIV infection as shown, for example, by a rapid loss of human CD4+ T cells from their blood. However, BLT mice pretreated with antiretroviral drugs (a mixture of emtricitabine and tenofovir disoproxil fumarate) were resistant to intravaginal HIV infection. As in human HIV infections, CD4+ T cells were also depleted in several other organs of the BLT mice after intravaginal HIV infection. Again, this depletion was prevented by antiretroviral pre-exposure prophylaxis. Finally, human CD4+ T cells also disappeared from the gut-associated lymphoid tissue (an important site for HIV replication and CD4+ T cell depletion during human HIV disease) of the BLT mice after infection with HIV.
What Do These Findings Mean?
These findings show that humanized BLT mice are susceptible to intravaginal infection with HIV and that many aspects of HIV infection in these mice closely mimic infection in people. In addition, by showing that pre-exposure prophylaxis with antiretroviral drugs prevents HIV infection, these results suggest that humanized BLT mice could be used to test new strategies designed to prevent intravaginal infection. As with all animal models, any approach that works in humanized BLT mice will still have to be tested in people. Nevertheless, these findings provide preclinical evidence that pre-exposure prophylaxis with antiretroviral drugs may be an effective way to prevent intravaginal transmission of HIV and, therefore, provide valuable support for clinical trials of this approach.
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0050016.
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS and on HIV infection in women
HIVInSite has comprehensive information on all aspects of HIV/AIDS, including articles on women and HIV and on safer sex, which includes information on pre-exposure prophylaxis and microbicides
Information is available from Avert, an international AIDS charity, on HIV prevention, on women, HIV, and AIDS, and on microbicides
The US Centers for Disease Control and Prevention provides information on HIV/AIDS, including information on HIV/AIDS among women and on CDC trials of pre-exposure prophylaxis for HIV prevention (in English and some information in Spanish)
PrEP Watch is a comprehensive information source on pre-exposure prophylaxis for HIV prevention
doi:10.1371/journal.pmed.0050016
PMCID: PMC2194746  PMID: 18198941
13.  Episodic Sexual Transmission of HIV Revealed by Molecular Phylodynamics 
PLoS Medicine  2008;5(3):e50.
Background
The structure of sexual contact networks plays a key role in the epidemiology of sexually transmitted infections, and their reconstruction from interview data has provided valuable insights into the spread of infection. For HIV, the long period of infectivity has made the interpretation of contact networks more difficult, and major discrepancies have been observed between the contact network and the transmission network revealed by viral phylogenetics. The high rate of HIV evolution in principle allows for detailed reconstruction of links between virus from different individuals, but often sampling has been too sparse to describe the structure of the transmission network. The aim of this study was to analyze a high-density sample of an HIV-infected population using recently developed techniques in phylogenetics to infer the short-term dynamics of the epidemic among men who have sex with men (MSM).
Methods and Findings
Sequences of the protease and reverse transcriptase coding regions from 2,126 patients, predominantly MSM, from London were compared: 402 of these showed a close match to at least one other subtype B sequence. Nine large clusters were identified on the basis of genetic distance; all were confirmed by Bayesian Monte Carlo Markov chain (MCMC) phylogenetic analysis. Overall, 25% of individuals with a close match with one sequence are linked to 10 or more others. Dated phylogenies of the clusters using a relaxed clock indicated that 65% of the transmissions within clusters took place between 1995 and 2000, and 25% occurred within 6 mo after infection. The likelihood that not all members of the clusters have been identified renders the latter observation conservative.
Conclusions
Reconstruction of the HIV transmission network using a dated phylogeny approach has revealed the HIV epidemic among MSM in London to have been episodic, with evidence of multiple clusters of transmissions dating to the late 1990s, a period when HIV prevalence is known to have doubled in this population. The quantitative description of the transmission dynamics among MSM will be important for parameterization of epidemiological models and in designing intervention strategies.
Using viral genotype data from HIV drug resistance testing at a London clinic, Andrew Leigh Brown and colleagues derive the structure of the transmission network through phylogenetic analysis.
Editors' Summary
Background.
Human immunodeficiency virus (HIV), the cause of acquired immunodeficiency syndrome (AIDS), is mainly spread through unprotected sex with an infected partner. Like other sexually transmitted diseases, HIV/AIDS spreads through networks of sexual contacts. The characteristics of these complex networks (which include people who have serial sexual relationships with single partners and people who have concurrent sexual relationships with several partners) affect how quickly diseases spread in the short term and how common the disease is in the long term. For many sexually transmitted diseases, sexual contact networks can be reconstructed from interview data. The information gained in this way can be used for partner notification so that transmitters of the disease and people who may have been unknowingly infected can be identified, treated, and advised about disease prevention. It can also be used to develop effective community-based prevention strategies.
Why Was This Study Done?
Although sexual contact networks have provided valuable information about the spread of many sexually transmitted diseases, they cannot easily be used to understand HIV transmission patterns. This is because the period of infectivity with HIV is long and the risk of infection from a single sexual contact with an infected person is low. Another way to understand the spread of HIV is through phylogenetics, which examines the genetic relatedness of viruses obtained from different individuals. Frequent small changes in the genetic blueprint of HIV allow the virus to avoid the human immune response and to become resistant to antiretroviral drugs. In this study, the researchers use recently developed analytical methods, viral sequences from a large proportion of a specific HIV-infected population, and information on when each sample was taken, to learn about transmission of HIV/AIDS in London among men who have sex with men (MSM; a term that encompasses gay, bisexual, and transgendered men and heterosexual men who sometimes have sex with men). This new approach, which combines information on viral genetic variation and viral population dynamics, is called “molecular phylodynamics.”
What Did the Researchers Do and Find?
The researchers compared the sequences of the genes encoding the HIV-1 protease and reverse transcriptase from more than 2,000 patients, mainly MSM, attending a large London HIV clinic between 1997 and 2003. 402 of these sequences closely matched at least one other subtype B sequence (the HIV/AIDS epidemic among MSM in the UK primarily involves HIV subtype B). Further analysis showed that the patients from whom this subset of sequences came formed six clusters of ten or more individuals, as well as many smaller clusters, based on the genetic relatedness of their HIV viruses. The researchers then used information on the date when each sample was collected and a “relaxed clock” approach (which accounts for the possibility that different sequences evolve at different rates) to determine dated phylogenies (patterns of genetic relatedness that indicate when gene sequences change) for the clusters. These phylogenies indicated that at least in one in four transmissions between the individuals in the large clusters occurred within 6 months of infection, and that most of the transmissions within each cluster occurred over periods of 3–4 years during the late 1990s.
What Do These Findings Mean?
This phylodynamic reconstruction of the HIV transmission network among MSM in a London clinic indicates that the HIV epidemic in this population has been episodic with multiple clusters of transmission occurring during the late 1990s, a time when the number of HIV infections in this population doubled. It also suggests that transmission of the virus during the early stages of HIV infection is likely to be an important driver of the epidemic. Whether these results apply more generally to the MSM population at risk for transmitting or acquiring HIV depends on whether the patients in this study are representative of that group. Additional studies are needed to determine this, but if the patterns revealed here are generalizable, then this quantitative description of HIV transmission dynamics should help in the design of strategies to strengthen HIV prevention among MSM.
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0050050.
Read a related PLoS Medicine Perspective article
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
HIV InSite has comprehensive information on all aspects of HIV/AIDS, including a list of organizations that provide information for gay men and MSM
The US Centers for Disease Control and Prevention provides information on HIV/AIDS and on HIV/AIDS among MSM (in English and Spanish)
Information is available from Avert, an international AIDS charity, on HIV, AIDS, and men who have sex with men
The Center for AIDS Prevention Studies (University of California, San Francisco) provides information on sexual networks and HIV prevention
The US National Center for Biotechnology Information provides a science primer on molecular phylogenetics
UK Collaborative Group on HIV Drug Resistance maintains a database of resistance tests
HIV i-Base offers HIV treatment information for health-care professionals and HIV-positive people
The NIH-funded HIV Sequence Database contains data on genetic sequences, resistance, immunology, and vaccine trials
doi:10.1371/journal.pmed.0050050
PMCID: PMC2267814  PMID: 18351795
14.  Home-Based Versus Mobile Clinic HIV Testing and Counseling in Rural Lesotho: A Cluster-Randomized Trial 
PLoS Medicine  2014;11(12):e1001768.
Niklaus Labhardt and colleagues investigate how different HIV testing and counseling strategies, based on home visits or mobile clinics, reach different populations in a rural African setting.
Please see later in the article for the Editors' Summary
Background
The success of HIV programs relies on widely accessible HIV testing and counseling (HTC) services at health facilities as well as in the community. Home-based HTC (HB-HTC) is a popular community-based approach to reach persons who do not test at health facilities. Data comparing HB-HTC to other community-based HTC approaches are very limited. This trial compares HB-HTC to mobile clinic HTC (MC-HTC).
Methods and Findings
The trial was powered to test the hypothesis of higher HTC uptake in HB-HTC campaigns than in MC-HTC campaigns. Twelve clusters were randomly allocated to HB-HTC or MC-HTC. The six clusters in the HB-HTC group received 30 1-d multi-disease campaigns (five villages per cluster) that delivered services by going door-to-door, whereas the six clusters in MC-HTC group received campaigns involving community gatherings in the 30 villages with subsequent service provision in mobile clinics. Time allocation and human resources were standardized and equal in both groups. All individuals accessing the campaigns with unknown HIV status or whose last HIV test was >12 wk ago and was negative were eligible. All outcomes were assessed at the individual level. Statistical analysis used multivariable logistic regression. Odds ratios and p-values were adjusted for gender, age, and cluster effect.
Out of 3,197 participants from the 12 clusters, 2,563 (80.2%) were eligible (HB-HTC: 1,171; MC-HTC: 1,392). The results for the primary outcomes were as follows. Overall HTC uptake was higher in the HB-HTC group than in the MC-HTC group (92.5% versus 86.7%; adjusted odds ratio [aOR]: 2.06; 95% CI: 1.18–3.60; p = 0. 011). Among adolescents and adults ≥12 y, HTC uptake did not differ significantly between the two groups; however, in children <12 y, HTC uptake was higher in the HB-HTC arm (87.5% versus 58.7%; aOR: 4.91; 95% CI: 2.41–10.0; p<0.001). Out of those who took up HTC, 114 (4.9%) tested HIV-positive, 39 (3.6%) in the HB-HTC arm and 75 (6.2%) in the MC-HTC arm (aOR: 0.64; 95% CI: 0.48–0.86; p = 0.002). Ten (25.6%) and 19 (25.3%) individuals in the HB-HTC and in the MC-HTC arms, respectively, linked to HIV care within 1 mo after testing positive. Findings for secondary outcomes were as follows: HB-HTC reached more first-time testers, particularly among adolescents and young adults, and had a higher proportion of men among participants. However, after adjusting for clustering, the difference in male participation was not significant anymore.
Age distribution among participants and immunological and clinical stages among persons newly diagnosed HIV-positive did not differ significantly between the two groups. Major study limitations included the campaigns' restriction to weekdays and a relatively low HIV prevalence among participants, the latter indicating that both arms may have reached an underexposed population.
Conclusions
This study demonstrates that both HB-HTC and MC-HTC can achieve high uptake of HTC. The choice between these two community-based strategies will depend on the objective of the activity: HB-HTC was better in reaching children, individuals who had never tested before, and men, while MC-HTC detected more new HIV infections. The low rate of linkage to care after a positive HIV test warrants future consideration of combining community-based HTC approaches with strategies to improve linkage to care for persons who test HIV-positive.
Trial registration
ClinicalTrials.gov NCT01459120
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Annually, about 2.3 million people become newly infected with HIV, the virus that causes AIDS by gradually destroying CD4 cells and other immune system cells, thereby leaving HIV-infected individuals susceptible to other serious infections. HIV can be transmitted through unprotected sex with an infected partner, from an HIV-positive mother to her unborn child, or through the injection of drugs with shared needles. Infection with HIV is usually diagnosed by looking for antibodies to HIV in the blood or saliva. After diagnosis, the progression of HIV infection is monitored by regularly counting the number of CD4 cells in the blood. Initiation of antiretroviral therapy (ART)—a combination of drugs that keeps HIV replication in check but that does not cure the infection—is recommended when an individual's CD4 count falls below 500 cells/µl or when he or she develops signs of advanced or severe disease, such as unusual infections.
Why Was This Study Done?
To control HIV/AIDS, HIV transmission needs to be reduced, and ART delivery needs to be increased. In settings of high HIV prevalence, universal coverage of HIV testing and counseling (HTC) is essential if these goals are to be met. Unfortunately, many people refuse “facility-based” HTC (HTC delivered at health care facilities) because they fear stigmatization and discrimination. Moreover, many people in resource-limited settings rarely visit health care facilities. Community-based HTC may be one way to increase the uptake of HTC, particularly among populations that are hard to reach, such as men and first-time testers, but which form of community-based HTC will be most effective? In this cluster-randomized trial, the researchers ask whether home-based HTC (HB-HTC)—community-based HTC in which health care workers go door-to-door to offer HTC to people in their own home—results in a higher uptake of HTC than HTC delivered through community gatherings and mobile clinics (MC-HTC) in two rural areas in Lesotho. Nearly a quarter of adults are HIV-positive in Lesotho, but only 61% of people who need ART currently receive treatment. A cluster-randomized trial compares outcomes in groups (clusters) of people chosen at random to receive different interventions.
What Did the Researchers Do and Find?
The researchers allocated 12 clusters, each comprising a health center and its catchment area, to the HB-HTC or MC-HTC intervention. In the HB-HTC arm (1,171 participants), HTC teams going door-to-door delivered a multi-disease campaign that included HTC to five villages in each cluster. In the MC-HTC arm (1,392 participants), the multi-disease campaign was delivered at community gatherings with subsequent service provision in mobile clinics. Overall, HTC uptake was higher in the HB-HTC arm than in the MC-HTC arm (92.5% and 86.7% uptake, respectively). Among participants aged ≥12 years, there was no significant difference in HTC uptake between the arms, whereas among children aged <12 years, HTC uptake was significantly higher in the HB-HTC arm than in the MC-HTC arm (87.5% versus 58.7%; a significant difference is a difference unlikely to have happened by chance). Among individuals who took up HTC, 3.6% and 6.2% tested positive for HIV in the HB-HTC arm and MC-HTC arm, respectively. In both arms, only a quarter of individuals who tested positive accessed HIV care within a month of their positive test result. Finally, HB-HTC reached more first-time testers (particularly among adolescents) and tended to reach more men than MC-HTC.
What Do These Findings Mean?
These findings suggest that, in rural Lesotho, both HB-HTC and MC-HTC delivered as part of a multi-disease campaign can achieve a high uptake of HTC. Various aspects of the trial design (for example, the small number of clusters) may limit the accuracy of the findings reported here. Notably, however, these findings suggest that the choice between HB-HTC and MC-HTC should be guided by the objective of the HTC intervention in specific settings. Where equity of access is of concern and where increased HTC coverage, particularly among groups in which HTC coverage is generally poor (including men, first-time testers, and children), is paramount, HB-HTC may be the preferred option. By contrast, the MC-HTC approach may be more appropriate in settings where the detection of new HIV infections is the major goal. Finally, and importantly, the findings of this trial highlight the need for further research into strategies designed to improve the linkage between HIV testing and enrollment into care.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001768.
The World Health Organization provides information on all aspects of HIV/AIDS, including information on HIV counseling and testing (in several languages)
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS and summaries of recent research findings on HIV care and treatment
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on the global HIV/AIDS epidemic, on HIV testing, and on HIV/AIDS in Lesotho
The UK National Health Service Choices website provides information (including personal stories) about HIV/AIDS
The “UNAIDS Report on the Global AIDS Epidemic 2013” provides up-to-date information about the AIDS epidemic and efforts to halt it
Stories about living with HIV/AIDS are available through Avert and through healthtalk.org
More information about this trial is available
doi:10.1371/journal.pmed.1001768
PMCID: PMC4267810  PMID: 25513807
15.  Supervised and Unsupervised Self-Testing for HIV in High- and Low-Risk Populations: A Systematic Review 
PLoS Medicine  2013;10(4):e1001414.
By systematically reviewing the literature, Nitika Pant Pai and colleagues assess the evidence base for HIV self tests both with and without supervision.
Background
Stigma, discrimination, lack of privacy, and long waiting times partly explain why six out of ten individuals living with HIV do not access facility-based testing. By circumventing these barriers, self-testing offers potential for more people to know their sero-status. Recent approval of an in-home HIV self test in the US has sparked self-testing initiatives, yet data on acceptability, feasibility, and linkages to care are limited. We systematically reviewed evidence on supervised (self-testing and counselling aided by a health care professional) and unsupervised (performed by self-tester with access to phone/internet counselling) self-testing strategies.
Methods and Findings
Seven databases (Medline [via PubMed], Biosis, PsycINFO, Cinahl, African Medicus, LILACS, and EMBASE) and conference abstracts of six major HIV/sexually transmitted infections conferences were searched from 1st January 2000–30th October 2012. 1,221 citations were identified and 21 studies included for review. Seven studies evaluated an unsupervised strategy and 14 evaluated a supervised strategy. For both strategies, data on acceptability (range: 74%–96%), preference (range: 61%–91%), and partner self-testing (range: 80%–97%) were high. A high specificity (range: 99.8%–100%) was observed for both strategies, while a lower sensitivity was reported in the unsupervised (range: 92.9%–100%; one study) versus supervised (range: 97.4%–97.9%; three studies) strategy. Regarding feasibility of linkage to counselling and care, 96% (n = 102/106) of individuals testing positive for HIV stated they would seek post-test counselling (unsupervised strategy, one study). No extreme adverse events were noted. The majority of data (n = 11,019/12,402 individuals, 89%) were from high-income settings and 71% (n = 15/21) of studies were cross-sectional in design, thus limiting our analysis.
Conclusions
Both supervised and unsupervised testing strategies were highly acceptable, preferred, and more likely to result in partner self-testing. However, no studies evaluated post-test linkage with counselling and treatment outcomes and reporting quality was poor. Thus, controlled trials of high quality from diverse settings are warranted to confirm and extend these findings.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
About 34 million people (most living in resource-limited countries) are currently infected with HIV, the virus that causes AIDS, and about 2.5 million people become infected with HIV every year. HIV is usually transmitted through unprotected sex with an infected partner. HIV infection is usually diagnosed by looking for antibodies to HIV in blood or saliva. Early during infection, the immune system responds to HIV by beginning to make antibodies that recognize the virus and target it for destruction. “Seroconversion”—the presence of detectable amounts of antibody in the blood or saliva—usually takes 6–12 weeks. Rapid antibody-based tests, which do not require laboratory facilities, can provide a preliminary result about an individual's HIV status from a simple oral swab or finger stick sample within 20 minutes. However preliminary rapid positive results have to be confirmed in a laboratory, which may take a few days or weeks. If positive, HIV infection can be controlled but not cured by taking a daily cocktail of powerful antiretroviral drugs throughout life.
Why Was This Study Done?
To reduce the spread of HIV, it is essential that HIV-positive individuals get tested, change behaviors avoid transmitting the virus to other people by, for example, always using a condom during sex, and if positive get on to treatment that is available worldwide. Treatment also reduces transmission of virus to the partner and controls the virus in the community. However, only half the people currently living with HIV know their HIV status, a state of affairs that increases the possibility of further HIV transmission to their partners and children. HIV positive individuals are diagnosed late with advanced HIV infection that costs health care services. Although health care facility-based HIV testing has been available for decades, people worry about stigma, visibility, and social discrimination. They also dislike the lack of privacy and do not like having to wait for their test results. Self-testing (i.e., self-test conduct and interpretation) might alleviate some of these barriers to testing by allowing individuals to determine their HIV status in the privacy of their home and could, therefore, increase the number of individuals aware of their HIV status. This could possibly reduce transmission and, through seeking linkages to care, bring HIV under control in communities. In some communities and countries, stigma of HIV prevents people from taking action about their HIV status. Indeed, an oral (saliva-based) HIV self-test kit is now available in the US. But how acceptable, feasible, and accurate is self-testing by lay people, and will people who find themselves self-test positive seek counseling and treatment? In this systematic review (a study that uses pre-defined criteria to identify all the research on a given topic), the researchers examine these issues by analyzing data from studies that have evaluated supervised self-testing (self-testing and counseling aided by a health-care professional) and unsupervised self-testing (self-testing performed without any help but with counseling available by phone or internet).
What Did the Researchers Do and Find?
The researchers identified 21 eligible studies, two-thirds of which evaluated oral self-testing and a third of which evaluated blood-based self-testing. Seven studies evaluated an unsupervised self-testing strategy and 14 evaluated a supervised strategy. Most of the data (89%) came from studies undertaken in high-income settings. The study populations varied from those at high risk of HIV infection to low-risk general populations. Across the studies, acceptability (defined as the number of people who actually self-tested divided by the number who consented to self-test) ranged from 74% to 96%. With both strategies, the specificity of self-testing (the chance of an HIV-negative person receiving a negative test result is true negative) was high but the sensitivity of self-testing (the chance of an HIV-positive person receiving a positive test result is indeed a true positive) was higher for supervised than for unsupervised testing. The researchers also found evidence that people preferred self-testing to facility-based testing and oral self-testing to blood-based self testing and, in one study, 96% of participants who self-tested positive sought post-testing counseling.
What Do These Findings Mean?
These findings provide new but limited information about the feasibility, acceptability, and accuracy of HIV self-testing. They suggest that it is feasible to implement both supervised and unsupervised self-testing, that both strategies are preferred to facility-based testing, but that the accuracy of self-testing is variable. However, most of the evidence considered by the researchers came from high-income countries and from observational studies of varying quality, and data on whether people self-testing positive sought post-testing counseling (linkage to care) were only available from one evaluation of unsupervised self-testing in the US. Consequently, although these findings suggest that self-testing could engage individuals in finding our their HIV status and thereby help modify behavior thus, reduce HIV transmission in the community, by increasing the proportion of people living with HIV who know their HIV status. The researchers suggested that more data from diverse settings and preferably from controlled randomized trials must be collected before any initiatives for global scale-up of self-testing for HIV infection are implemented.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001414.
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS and summaries of recent research findings on HIV care and treatment
Information is available from Avert, an international AIDS charity on many aspects of HIV/AIDS, including information on HIV testing, and on HIV transmission and testing (in English and Spanish)
The UK National Health Service Choices website provides information about all aspects of HIV and AIDS; a “behind the headlines” article provides details about the 2012 US approval for an over-the-counter HIV home-use test
The 2012 World AIDS Day Report provides information about the percentage of people living with HIV who are aware of their HIV status in various African countries, as well as up-to-date information about the AIDS epidemic
Patient stories about living with HIV/AIDS are available through Avert; the nonprofit website Healthtalkonline also provides personal stories about living with HIV, including stories about getting a diagnosis
doi:10.1371/journal.pmed.1001414
PMCID: PMC3614510  PMID: 23565066
16.  Pregnancy and Infant Outcomes among HIV-Infected Women Taking Long-Term ART with and without Tenofovir in the DART Trial 
PLoS Medicine  2012;9(5):e1001217.
Diana Gibb and colleagues investigate the effect of in utero tenofovir exposure by analyzing the pregnancy and infant outcomes of HIV-infected women enrolled in the DART trial.
Background
Few data have described long-term outcomes for infants born to HIV-infected African women taking antiretroviral therapy (ART) in pregnancy. This is particularly true for World Health Organization (WHO)–recommended tenofovir-containing first-line regimens, which are increasingly used and known to cause renal and bone toxicities; concerns have been raised about potential toxicity in babies due to in utero tenofovir exposure.
Methods and Findings
Pregnancy outcome and maternal/infant ART were collected in Ugandan/Zimbabwean HIV-infected women initiating ART during The Development of AntiRetroviral Therapy in Africa (DART) trial, which compared routine laboratory monitoring (CD4; toxicity) versus clinically driven monitoring. Women were followed 15 January 2003 to 28 September 2009. Infant feeding, clinical status, and biochemistry/haematology results were collected in a separate infant study. Effect of in utero ART exposure on infant growth was analysed using random effects models.
382 pregnancies occurred in 302/1,867 (16%) women (4.4/100 woman-years [95% CI 4.0–4.9]). 226/390 (58%) outcomes were live-births, 27 (7%) stillbirths (≥22 wk), and 137 (35%) terminations/miscarriages (<22 wk). Of 226 live-births, seven (3%) infants died <2 wk from perinatal causes and there were seven (3%) congenital abnormalities, with no effect of in utero tenofovir exposure (p>0.4). Of 219 surviving infants, 182 (83%) enrolled in the follow-up study; median (interquartile range [IQR]) age at last visit was 25 (12–38) months. From mothers' ART, 62/9/111 infants had no/20%–89%/≥90% in utero tenofovir exposure; most were also zidovudine/lamivudine exposed. All 172 infants tested were HIV-negative (ten untested). Only 73/182(40%) infants were breast-fed for median 94 (IQR 75–212) days. Overall, 14 infants died at median (IQR) age 9 (3–23) months, giving 5% 12-month mortality; six of 14 were HIV-uninfected; eight untested infants died of respiratory infection (three), sepsis (two), burns (one), measles (one), unknown (one). During follow-up, no bone fractures were reported to have occurred; 12/368 creatinines and seven out of 305 phosphates were grade one (16) or two (three) in 14 children with no effect of in utero tenofovir (p>0.1). There was no evidence that in utero tenofovir affected growth after 2 years (p = 0.38). Attained height- and weight for age were similar to general (HIV-uninfected) Ugandan populations. Study limitations included relatively small size and lack of randomisation to maternal ART regimens.
Conclusions
Overall 1-year 5% infant mortality was similar to the 2%–4% post-neonatal mortality observed in this region. No increase in congenital, renal, or growth abnormalities was observed with in utero tenofovir exposure. Although some infants died untested, absence of recorded HIV infection with combination ART in pregnancy is encouraging. Detailed safety of tenofovir for pre-exposure prophylaxis will need confirmation from longer term follow-up of larger numbers of exposed children.
Trial registration
www.controlled-trials.com ISRCTN13968779
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Currently, about 34 million people (mostly in low- and middle-income countries) are infected with HIV, the virus that causes AIDS. At the beginning of the epidemic, more men than women were infected with HIV but now about half of all people living with HIV/AIDS are women, most of who became infected through unprotected sex with an infected partner. In sub-Saharan Africa alone, 12 million women are HIV-positive. Worldwide, HIV/AIDS is the leading cause of death among women of child-bearing age. Moreover, most of the 400,000 children who become infected with HIV every year acquire the virus from their mother during pregnancy or birth, or through breastfeeding, so-called mother-to-child transmission (MTCT). Combination antiretroviral therapy (ART)—treatment with cocktails of powerful antiretroviral drugs—reduces HIV-related illness and death among women, and ART given to HIV-positive mothers during pregnancy and delivery and to their newborn babies greatly reduces MTCT.
Why Was This Study Done?
Because of ongoing international efforts to increase ART coverage, more HIV-positive women in Africa have access to ART now than ever before. However, little is known about pregnancy outcomes among HIV-infected African women taking ART throughout pregnancy for their own health or about the long-term outcomes of their offspring. In particular, few studies have examined the effect of taking tenofovir (an antiretroviral drug that is now recommended as part of first-line ART) throughout pregnancy. Tenofovir readily crosses from mother to child during pregnancy and, in animal experiments, high doses of tenofovir given during pregnancy caused bone demineralization (which weakens bones), kidney problems, and impaired growth among offspring. In this study, the researchers analyze data collected on pregnancy and infant outcomes among Ugandan and Zimbabwean HIV-positive women who took ART throughout pregnancy in the Development of AntiRetroviral Therapy in Africa (DART) trial. This trial was designed to test whether ART could be safely and effectively delivered in Africa without access to the expensive laboratory tests that are routinely used to monitor ART toxicity and efficacy in developed countries.
What Did the Researchers Do and Find?
The pregnancy outcomes of 302 women who became pregnant during the DART trial and information on birth defects among their babies were collected as part of the DART protocol; information on the survival, growth, and development of the infants born to these women was collected in a separate infant study. Most of the women who became pregnant were taking tenofovir-containing ART before and throughout their pregnancies. 58% of the pregnancies resulted in a live birth, 7% resulted in a stillbirth (birth of a dead baby at any time from 22 weeks gestation to the end of pregnancy), and 35% resulted in a termination or miscarriage (before 22 weeks gestation). Of the 226 live births, seven infants died within 2 weeks and seven had birth defects. Similar proportions of the infants exposed and not exposed to tenofovir during pregnancy died soon after birth or had birth defects. Of the 182 surviving infants who were enrolled in the infant study, 14 subsequently died at an average age of 9 months, giving a 1-year mortality of 5%. None of the surviving children who were tested (172 infants) were HIV infected. No bone fractures or major kidney problems occurred during follow-up and prebirth exposure to tenofovir in utero had no effect on growth or weight gain at 2 years (in contrast to a previous US study).
What Do These Findings Mean?
By showing that prebirth tenofovir exposure does not affect pregnancy outcomes or increase birth defects, growth abnormalities, or kidney problems, these findings support the use of tenofovir-containing ART during pregnancy among HIV-positive African women, and suggest that it could also be used to prevent women of child-bearing age acquiring HIV-infection heterosexually. Notably, the observed 5% 1-year infant mortality is similar to the 2%–4% infant mortality normally seen in the region. The absence of HIV infection among the infants born to the DART participants is also encouraging. However, this is a small study (only 111 infants were exposed to tenofovir throughout pregnancy) and women were not randomly assigned to receive tenofovir-containing ART. Consequently, more studies are needed to confirm that tenofovir exposure during pregnancy does not affect pregnancy outcomes or have any long-term effects on infants. Such studies are essential because the use of tenofovir as a treatment for women who are HIV-positive is likely to increase and tenofovir may also be used in the future to prevent HIV acquisition in HIV-uninfected women.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001217.
Information is available from the US National Institute of Allergy and infectious diseases on all aspects of HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS, and summaries of recent research findings on HIV care and treatment (in several languages)
Information is available from Avert, an international AIDS nonprofit on many aspects of HIV/AIDS, including detailed information on HIV/AIDS treatment and care, women, HIV and AIDS, children, HIV and AIDS, and on HIV/AIDS and pregnancy (some information in English and Spanish); personal stories of women living with HIV are available
More information about the DART trial is available
Additional patient stories about living with HIV/AIDS are available through the nonprofit website Healthtalkonline
doi:10.1371/journal.pmed.1001217
PMCID: PMC3352861  PMID: 22615543
17.  HIV Shedding from Male Circumcision Wounds in HIV-Infected Men: A Prospective Cohort Study 
PLoS Medicine  2015;12(4):e1001820.
Background
A randomized trial of voluntary medical male circumcision (MC) of HIV—infected men reported increased HIV transmission to female partners among men who resumed sexual intercourse prior to wound healing. We conducted a prospective observational study to assess penile HIV shedding after MC.
Methods and Findings
HIV shedding was evaluated among 223 HIV—infected men (183 self—reported not receiving antiretroviral therapy [ART], 11 self—reported receiving ART and had a detectable plasma viral load [VL], and 29 self—reported receiving ART and had an undetectable plasma VL [<400 copies/ml]) in Rakai, Uganda, between June 2009 and April 2012. Preoperative and weekly penile lavages collected for 6 wk and then at 12 wk were tested for HIV shedding and VL using a real—time quantitative PCR assay. Unadjusted prevalence risk ratios (PRRs) and adjusted PRRs (adjPRRs) of HIV shedding were estimated using modified Poisson regression with robust variance. HIV shedding was detected in 9.3% (17/183) of men not on ART prior to surgery and 39.3% (72/183) of these men during the entire study. Relative to baseline, the proportion shedding was significantly increased after MC at 1 wk (PRR = 1.87, 95% CI = 1.12–3.14, p = 0.012), 2 wk (PRR = 3.16, 95% CI = 1.94–5.13, p < 0.001), and 3 wk (PRR = 1.98, 95% CI = 1.19–3.28, p = 0.008) after MC. However, compared to baseline, HIV shedding was decreased by 6 wk after MC (PRR = 0.27, 95% CI = 0.09–0.83, p = 0.023) and remained suppressed at 12 wk after MC (PRR = 0.19, 95% CI = 0.06–0.64, p = 0.008). Detectable HIV shedding from MC wounds occurred in more study visits among men with an HIV plasma VL > 50,000 copies/ml than among those with an HIV plasma VL < 400 copies/ml (adjPRR = 10.3, 95% CI = 4.25–24.90, p < 0.001). Detectable HIV shedding was less common in visits from men with healed MC wounds compared to visits from men without healed wounds (adjPRR = 0.12, 95% CI = 0.07–0.23, p < 0.001) and in visits from men on ART with undetectable plasma VL compared to men not on ART (PRR = 0.15, 95% CI = 0.05–0.43, p = 0.001). Among men with detectable penile HIV shedding, the median log10 HIV copies/milliliter of lavage fluid was significantly lower in men with ART—induced undetectable plasma VL (1.93, interquartile range [IQR] = 1.83–2.14) than in men not on ART (2.63, IQR = 2.28–3.22, p < 0.001). Limitations of this observational study include significant differences in baseline covariates, lack of confirmed receipt of ART for individuals who reported ART use, and lack of information on potential ART initiation during follow—up for those who were not on ART at enrollment.
Conclusion
Penile HIV shedding is significantly reduced after healing of MC wounds. Lower plasma VL is associated with decreased frequency and quantity of HIV shedding from MC wounds. Starting ART prior to MC should be considered to reduce male-to-female HIV transmission risk. Research is needed to assess the time on ART required to decrease shedding, and the acceptability and feasibility of initiating ART at the time of MC.
In this prospective cohort study, Aaron Tobian and colleagues examine the associations between male circumcision wound healing, as well as plasma viral load, and HIV shedding from male circumcision wounds.
Editors' Summary
Background
About 35 million people are currently infected with HIV, the virus that causes AIDS by destroying immune system cells, and every year, 2 million more people become HIV-positive. Antiretroviral therapy (ART) can keep HIV in check, but there is no cure for AIDS. Consequently, prevention of HIV acquisition and transmission is an important component of efforts to control the AIDS epidemic. Because HIV is most often spread through unprotected sex with an infected partner, individuals can reduce their risk of becoming HIV-positive by abstaining from sex, by having only one or a few partners, and by using male or female condoms. In addition, three trials undertaken in sub-Saharan Africa a decade ago showed that male circumcision—the surgical removal of the foreskin, a loose fold of skin that covers the head of the penis—can halve the HIV acquisition rate in men. Thus, since 2007, the World Health Organization (WHO) has recommended voluntary medical male circumcision for individuals living in countries with high HIV prevalence as part of its HIV prevention strategy.
Why Was This Study Done?
With the rollout of voluntary medical male circumcision programs, circumcision has become more normative (regarded as acceptable), and HIV-positive men are increasingly requesting circumcision because they want to avoid any stigma associated with being uncircumcised and because circumcision provides health benefits. WHO recommends that, although circumcision should not be promoted for HIV-positive men, voluntary circumcision programs should operate on HIV-positive men if they request circumcision. However, in a trial of circumcision of HIV-infected men, HIV transmission to their female partners increased if the couples had sexual intercourse before the circumcision wound had healed. Moreover, in studies of current male circumcision programs, two-thirds of married men and a third of all men reported that they resumed sexual intercourse before their circumcision wounds had healed. Thus, better understanding of how male circumcision increases HIV transmission to female partners is essential, and improved ways to prevent transmission in the post-surgical period are needed. Here, in a prospective observational study (an investigation that collects data over time from people undergoing a specific procedure), the researchers assess HIV shedding from the penis after circumcision.
What Did the Researchers Do and Find?
The researchers evaluated penile HIV shedding among 223 HIV-infected men (183 men who self-reported not being on ART and 40 men who self-reported being on ART, 29 of whom had no detectable virus in their blood) living in Rakai, Uganda, by examining preoperative and postoperative penile lavage (wash) samples. Viral shedding was detected in 9.3% of the men not on ART before surgery and in 39.3% of these men during the entire study. Relative to baseline, a greater proportion of men shed virus at one, two, and three weeks after circumcision, but a lower proportion shed virus at six and twelve weeks after circumcision. HIV shedding was more frequent among men with a high amount of virus in their blood (a high viral load) than among men with a low viral load. Moreover, the frequency of HIV shedding was lower in visits from men with healed circumcision wounds than in visits from men with unhealed wounds, and in visits from men on ART with no detectable virus in their blood than in visits from men not on ART men. Finally, among men with detectable penile HIV shedding, men on ART with no detectable virus in their blood shed fewer copies of virus than men not on ART.
What Do These Findings Mean?
The findings suggest that healed circumcision wounds are associated with reduced penile HIV shedding in HIV-positive men compared to unhealed circumcision wounds and HIV shedding prior to circumcision In addition, they suggest that a lower HIV viral load in the blood is associated with a decreased frequency and quantity of HIV shedding from circumcision wounds. Because this was an observational study, these findings cannot prove that healed wounds or reduced blood viral load actually caused reduced penile HIV shedding. Moreover, the accuracy of these findings may be affected by the lack of information on ART initiation during follow-up among men not initially on ART and by reliance on ART self-report. Nevertheless, these findings highlight the importance of counseling HIV-positive men undergoing circumcision to avoid sexual intercourse until their circumcision wound heals. In addition, these findings suggest that it might be possible to reduce HIV transmission among HIV-positive men immediately after circumcision by starting these individuals on ART before circumcision. Further research is needed to assess how long before circumcision ART should be initiated and to assess the acceptability and feasibility of initiating ART concurrent with circumcision.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001820.
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS, summaries of recent research findings on HIV care and treatment, information on male circumcision for the prevention of HIV transmission, and personal stories about living with HIV/AIDS
Information is available from Avert, an international AIDS charity on many aspects of HIV/AIDS, including information on HIV prevention, on voluntary medical male circumcision for HIV prevention, and on HIV/AIDS in sub-Saharan Africa; Avert also provides personal stories about living with HIV/AIDS
The World Health Organization provides information on all aspects of HIV/AIDS (in several languages), including on voluntary medical male circumcision for HIV prevention
The UNAIDS Fast-Track Strategy to End the AIDS Epidemic by 2030 provides up-to-date information about the AIDS epidemic and efforts to halt it
The Clearinghouse on Male Circumcision for HIV Prevention provides up-to-date information and resources on male circumcision for HIV prevention
doi:10.1371/journal.pmed.1001820
PMCID: PMC4412625  PMID: 25919012
18.  HLA Alleles Associated with Delayed Progression to AIDS Contribute Strongly to the Initial CD8+ T Cell Response against HIV-1 
PLoS Medicine  2006;3(10):e403.
Background
Very little is known about the immunodominance patterns of HIV-1-specific T cell responses during primary HIV-1 infection and the reasons for human lymphocyte antigen (HLA) modulation of disease progression.
Methods and Findings
In a cohort of 104 individuals with primary HIV-1 infection, we demonstrate that a subset of CD8+ T cell epitopes within HIV-1 are consistently targeted early after infection, while other epitopes subsequently targeted through the same HLA class I alleles are rarely recognized. Certain HLA alleles consistently contributed more than others to the total virus-specific CD8+ T cell response during primary infection, and also reduced the absolute magnitude of responses restricted by other alleles if coexpressed in the same individual, consistent with immunodomination. Furthermore, individual HLA class I alleles that have been associated with slower HIV-1 disease progression contributed strongly to the total HIV-1-specific CD8+ T cell response during primary infection.
Conclusions
These data demonstrate consistent immunodominance patterns of HIV-1-specific CD8+ T cell responses during primary infection and provide a mechanistic explanation for the protective effect of specific HLA class I alleles on HIV-1 disease progression.
A subset of CD8+ T cell epitopes within HIV-1 are consistently targeted early after infection. This could explain some of the protective effect of certain HLA class I alleles on HIV-1 disease progression.
Editors' Summary
Background.
Nearly 15,000 new HIV infections occur each day. There is no cure for HIV, and the treatments currently used to prevent people with HIV from dying are expensive and unavailable to many who need them. There is also no vaccine to prevent HIV. An effective vaccine would somehow induce the immune system to prevent the virus from reaching destructive levels in the body, but how to design such a vaccine is unknown.
In most people infected with HIV, the immune system doesn't keep the AIDS virus in check over the long term. It has been known for a long time, however, that the body somehow brings the virus under control within a few weeks following infection, after which, in the absence of treatment, the amount of virus gradually increases again over time. Exactly why the amount of virus drops after initial infection is not fully understood, but there is good evidence that the white blood cells called CD8 T lymphocytes, which can kill other cells infected with viruses, are at least partially responsible for initially bringing HIV infection under control.
In order for a CD8 T lymphocyte to recognize and kill an infected cell, that cell has to display some part of the infecting virus on its surface. There are many possible fragments of HIV that can activate CD8 T cells, although some of these fragments appear more effective than others at provoking a strong killer response. Also, in order to activate CD8 T cells the viral fragments must bind to and be presented by a particular kind of protein called HLA on the surface of the infected cells. There are hundreds of varieties of HLA in the human population, allowing our immune systems to recognize many parts of many different viruses. (Each person can have up to six different kinds of HLA class I on the surface of his or her cells). A few specific types of HLA have been found to provide some advantage in keeping the AIDS virus under control, possibly because they present fragments of the virus that are particularly good at activating CD8 T cells.
Why Was This Study Done?
The researchers wanted to find out whether specific HLA types and specific protein fragments (peptides) of the AIDS virus are particularly important in helping CD8 T cells control HIV. Specifically, they wanted to find out the very earliest protein fragments recognized, since these might be particularly important in keeping the virus in check. They also wanted to see if these particular HLA-peptide combinations might affect the long-term health of people with HIV infection. Finding specific combinations of peptide and HLA that give rise to strong control of HIV could help in the design of an effective AIDS vaccine.
What Did the Researchers Do and Find?
The researchers studied CD8 T cells in blood samples from 104 people in the early stages of HIV infection. They used DNA analysis to determine which HLA types were present in each participant, and then chose, from among 173 different protein fragments of HIV, the peptides that are known to bind to and be presented by the participant's HLA types. The ability of these peptides to activate the participant's CD8 T cells was measured in the laboratory.
These studies found that for many types of HLA, there were a few specific viral peptides that triggered most of the CD8 T cell activity found in early HIV infection, when the amount of virus in the blood is being lowered by this response. A few types of HLA were found to contribute more strongly than others to CD8 T-cell activity in early HIV infection. These same types of HLA are also found in people who tend to remain healthier for a longer time after becoming infected with HIV.
What Do These Findings Mean?
This study provides evidence that ability of CD8 T cells to keep HIV under control in the first few months following infection depends on a person's HLA composition, and that this early CD8 T cell activity sets the stage for the long-term balance between the body and the virus. Knowing the particular peptide–HLA combinations that dominate the early immune response (when the immune system appears to be bringing the virus under control) might be of use in designing an HIV vaccine. Because this study was done in people already infected with HIV, however, it remains unclear whether a vaccine based on this knowledge would actually prevent new HIV infection or improve health after infection, even in people with “good” HLA types.
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0030403.
The UCSF Center for HIV Information's HIV InSite includes resources on HIV immunology and vaccine development
The Los Alamos Natural Laboratory HIV Molecular Immunology Database contains information for researchers on HIV peptides, HLA, and CD8 T cell responses
The International AIDS Vaccine Initiative (IAVI) Web site provides policy and scientific information on the global AIDS vaccine effort
The Massachuetts General Hospital Web site contains information about their HIV-1 research programs
doi:10.1371/journal.pmed.0030403
PMCID: PMC1626551  PMID: 17076553
19.  The Role of Viral Introductions in Sustaining Community-Based HIV Epidemics in Rural Uganda: Evidence from Spatial Clustering, Phylogenetics, and Egocentric Transmission Models 
PLoS Medicine  2014;11(3):e1001610.
Using different approaches to investigate HIV transmission patterns, Justin Lessler and colleagues find that extra-community HIV introductions are frequent and likely play a role in sustaining the epidemic in the Rakai community.
Please see later in the article for the Editors' Summary
Background
It is often assumed that local sexual networks play a dominant role in HIV spread in sub-Saharan Africa. The aim of this study was to determine the extent to which continued HIV transmission in rural communities—home to two-thirds of the African population—is driven by intra-community sexual networks versus viral introductions from outside of communities.
Methods and Findings
We analyzed the spatial dynamics of HIV transmission in rural Rakai District, Uganda, using data from a cohort of 14,594 individuals within 46 communities. We applied spatial clustering statistics, viral phylogenetics, and probabilistic transmission models to quantify the relative contribution of viral introductions into communities versus community- and household-based transmission to HIV incidence. Individuals living in households with HIV-incident (n = 189) or HIV-prevalent (n = 1,597) persons were 3.2 (95% CI: 2.7–3.7) times more likely to be HIV infected themselves compared to the population in general, but spatial clustering outside of households was relatively weak and was confined to distances <500 m. Phylogenetic analyses of gag and env genes suggest that chains of transmission frequently cross community boundaries. A total of 95 phylogenetic clusters were identified, of which 44% (42/95) were two individuals sharing a household. Among the remaining clusters, 72% (38/53) crossed community boundaries. Using the locations of self-reported sexual partners, we estimate that 39% (95% CI: 34%–42%) of new viral transmissions occur within stable household partnerships, and that among those infected by extra-household sexual partners, 62% (95% CI: 55%–70%) are infected by sexual partners from outside their community. These results rely on the representativeness of the sample and the quality of self-reported partnership data and may not reflect HIV transmission patterns outside of Rakai.
Conclusions
Our findings suggest that HIV introductions into communities are common and account for a significant proportion of new HIV infections acquired outside of households in rural Uganda, though the extent to which this is true elsewhere in Africa remains unknown. Our results also suggest that HIV prevention efforts should be implemented at spatial scales broader than the community and should target key populations likely responsible for introductions into communities.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
About 35 million people (25 million of whom live in sub-Saharan Africa) are currently infected with HIV, the virus that causes AIDS, and about 2.3 million people become newly infected every year. HIV destroys immune system cells, leaving infected individuals susceptible to other infections. HIV infection can be controlled by taking antiretroviral drugs (antiretroviral therapy, or ART) daily throughout life. Although originally available only to people living in wealthy countries, recent political efforts mean that 9.7 million people in low- and middle-income countries now have access to ART. However, ART does not cure HIV infection, so prevention of viral transmission remains extremely important. Because HIV is usually transmitted through unprotected sex with an infected partner, individuals can reduce their risk of infection by abstaining from sex, by having one or a few partners, and by using condoms. Male circumcision also reduces HIV transmission. In addition to reducing illness and death among HIV-positive people, ART also reduces HIV transmission.
Why Was This Study Done?
Effective HIV control requires an understanding of how HIV spreads through sexual networks. These networks include sexual partnerships between individuals in households, between community members in different households, and between individuals from different communities. Local sexual networks (household and intra-community sexual partnerships) are sometimes assumed to be the dominant driving force in HIV spread in sub-Saharan Africa, but are viral introductions from sexual partnerships with individuals outside the community also important? This question needs answering because the effectiveness of interventions such as ART as prevention partly depends on how many new infections in an intervention area are attributable to infection from partners residing in that area and how many are attributable to infection from partners living elsewhere. Here, the researchers use three analytical methods—spatial clustering statistics, viral phylogenetics, and egocentric transmission modeling—to ask whether HIV transmission in rural Uganda is driven predominantly by intra-community sexual networks. Spatial clustering analysis uses the geographical coordinates of households to measure the tendency of HIV-infected people to cluster spatially at scales consistent with community transmission. Viral phylogenetic analysis examines the genetic relatedness of viruses; if transmission is through local networks, viruses in newly infected individuals should more closely resemble viruses in other community members than those in people outside the community. Egocentric transmission modelling uses information on the locations of recent sexual partners to estimate the proportions of new transmissions from household, intra-community, and extra-community partners.
What Did the Researchers Do and Find?
The researchers applied their three analytical methods to data collected from 14,594 individuals living in 46 communities (governmental administrative units) in Rakai District, Uganda. Spatial clustering analysis indicated that individuals who lived in households with individuals with incident HIV (newly diagnosed) or prevalent HIV (previously diagnosed) were 3.2 times more likely than the general population to be HIV-positive themselves. Spatial clustering outside households was relatively weak, however, and was confined to distances of less than half a kilometer. Viral phylogenetic analysis indicated that 44% of phylogenetic clusters (viruses with related genetic sequences found in more than one individual) were within households, but that 40% of clusters crossed community borders. Finally, analysis of the locations of self-reported sexual partners indicated that 39% of new viral transmissions occurred within stable household partnerships, but that among people newly infected by extra-household partners, nearly two-thirds were infected by partners from outside their community.
What Do These Findings Mean?
The results of all three analyses suggest that HIV introductions into communities are frequent and are likely to play an important role in sustaining HIV transmission in the Rakai District. Specifically, within this rural HIV-endemic region (a region where HIV infection is always present), viral introductions combined with intra-household transmission account for the majority of new infections, although community-based sexual networks also play a critical role in HIV transmission. These findings may not be generalizable to the broader Ugandan population or to other regions of Africa, and their accuracy is likely to be limited by the use of self-reported sexual partner data. Nevertheless, these findings indicate that the dynamics of HIV transmission in rural Uganda (and probably elsewhere) are complex. Consequently, to halt the spread of HIV, prevention efforts will need to be implemented at spatial scales broader than individual communities, and key populations that are likely to introduce HIV into communities will need to be targeted.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001610.
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS, and summaries of recent research findings on HIV care and treatment
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on HIV and AIDS in Uganda and on HIV prevention strategies (in English and Spanish)
The UNAIDS Report on the Global AIDS Epidemic 2013 provides up-to-date information about the AIDS epidemic and efforts to halt it
The Center for AIDS Prevention Studies (University of California, San Francisco) has a fact sheet about sexual networks and HIV prevention
Wikipedia provides information on spatial clustering analysis (note that Wikipedia is a free online encyclopedia that anyone can edit; available in several languages)
A PLOS Computational Biology Topic Page (a review article that is a published copy of record of a dynamic version of the article as found in Wikipedia) about viral phylodynamics is available
Personal stories about living with HIV/AIDS are available through Avert, NAM/aidsmap, and Healthtalkonline
doi:10.1371/journal.pmed.1001610
PMCID: PMC3942316  PMID: 24595023
20.  Selection of an HLA-C*03:04-Restricted HIV-1 p24 Gag Sequence Variant Is Associated with Viral Escape from KIR2DL3+ Natural Killer Cells: Data from an Observational Cohort in South Africa 
PLoS Medicine  2015;12(11):e1001900.
Background
Viruses can evade immune surveillance, but the underlying mechanisms are insufficiently understood. Here, we sought to understand the mechanisms by which natural killer (NK) cells recognize HIV-1-infected cells and how this virus can evade NK-cell-mediated immune pressure.
Methods and Findings
Two sequence mutations in p24 Gag associated with the presence of specific KIR/HLA combined genotypes were identified in HIV-1 clade C viruses from a large cohort of infected, untreated individuals in South Africa (n = 392), suggesting viral escape from KIR+ NK cells through sequence variations within HLA class I—presented epitopes. One sequence polymorphism at position 303 of p24 Gag (TGag303V), selected for in infected individuals with both KIR2DL3 and HLA-C*03:04, enabled significantly better binding of the inhibitory KIR2DL3 receptor to HLA-C*03:04-expressing cells presenting this variant epitope compared to the wild-type epitope (wild-type mean 18.01 ± 10.45 standard deviation [SD] and variant mean 44.67 ± 14.42 SD, p = 0.002). Furthermore, activation of primary KIR2DL3+ NK cells from healthy donors in response to HLA-C*03:04+ target cells presenting the variant epitope was significantly reduced in comparison to cells presenting the wild-type sequence (wild-type mean 0.78 ± 0.07 standard error of the mean [SEM] and variant mean 0.63 ± 0.07 SEM, p = 0.012). Structural modeling and surface plasmon resonance of KIR/peptide/HLA interactions in the context of the different viral sequence variants studied supported these results. Future studies will be needed to assess processing and antigen presentation of the investigated HIV-1 epitope in natural infection, and the consequences for viral control.
Conclusions
These data provide novel insights into how viruses can evade NK cell immunity through the selection of mutations in HLA-presented epitopes that enhance binding to inhibitory NK cell receptors. Better understanding of the mechanisms by which HIV-1 evades NK-cell-mediated immune pressure and the functional validation of a structural modeling approach will facilitate the development of novel targeted immune interventions to harness the antiviral activities of NK cells.
An analysis from a cohort in South Africa reveals how the HIV virus may escape NK cell immunity by acquiring mutations in HLA-mediated epitopes, which affect binding to NK cell receptors.
Editors' Summary
Background
Throughout life, our immune system—a complex network of cells, tissues, and organs—protects us from attack by viruses, bacteria, parasites, and fungi. The body’s first line of defense against these “pathogens” is the innate immune system, a collection of cells and proteins that is always ready to identify and kill a wide range of foreign invaders. As well as directly killing pathogens, the innate immune system activates the adaptive immune response, which recognizes and kills specific pathogens and is responsible for immunological memory. Most pathogens are dispatched quickly and effectively by the two arms of the immune system, but some infectious agents have found ways to evade the immune response. For example, infection with HIV-1, the virus that causes AIDS, results in prolonged, continuous viral replication even though the human body mounts a vigorous HIV-1-specific immune response. In large part, HIV-1’s evasion of the immune response reflects its ability to kill virus-specific CD4 lymphocytes, which are needed to help other immune system cells kill HIV-1-infected cells. In addition, the proteins on the surface of HIV-1 that are recognized by the human immune system (viral antigens) frequently acquire changes (mutations) that make it harder for the immune system to clear HIV-1 from the human body.
Why Was This Study Done?
Viruses evade immune surveillance in many ways, and if we understood the mechanisms underlying immune evasion better, it might be possible to develop targeted immune interventions to deal with viruses such as HIV-1. Here, the researchers investigate how natural killer (NK) cells, a type of lymphocyte that is an important component of the innate antiviral immune response, recognize HIV-infected cells and how HIV-1 evades NK-cell-mediated immune pressure. NK cell activation is determined by the integration of inhibitory and activating signals delivered to the cells by several different receptor families, including the family of killer-cell immunoglobulin-like receptors (KIRs). KIRs mainly bind to human leukocyte antigen (HLA) class I molecules (ligands) on their target cells. HLA class I proteins display fragments (epitopes; peptides recognized by the immune system) of pathogens present in infected cells on the cell surface so that the immune system knows that that cell needs destroying. The binding of distinct KIRs to HLA class I ligands depends on both the sequence of the HLA class I molecule and the sequence of the epitope presented by that HLA class I molecule. Thus, the researchers hypothesized that HIV-1 might evade NK-cell-mediated immune surveillance by acquiring mutations within epitopes presented by HLA class I molecules that enhance the engagement of inhibitory KIRs on NK cells, thereby inhibiting NK cell activity.
What Did the Researchers Do and Find?
To investigate this model, the researchers asked whether any polymorphisms (naturally occurring genetic variations) in the HIV-1 gene encoding the p24 Gag protein were selected on a population level in HIV-1-infected individuals expressing specific combinations of KIRs and HLA class I ligands. Using statistical methods to identify KIR/HLA combined genotypes in a large group of untreated HIV-1-infected individuals from South Africa, they showed that a specific sequence polymorphism in p24 Gag was selected for in individuals expressing both HLA-C*03:04 and KIR2DL3. Functional studies showed that the selection of this variant HIV-1 epitope resulted in better binding of KIR2DL3, an inhibitory KIR, to HLA-C*03:04 than the wild-type epitope. Moreover, the activation of KIR2DL3-positive NK cells from healthy donors in response to HLA-C*03:04-positive target cells presenting the variant epitope was significantly reduced compared to the activation of KIR2DL3-positive NK cells in response to target cells presenting the wild-type epitope.
What Do These Findings Mean?
Further studies are needed to assess the consequences of this and other viral sequence variants for viral fitness, the processing and presentation of the mutant epitope during natural infections, and the control of HIV-1 replication in patients. However, these findings provide new insights into how HIV-1 (and possibly other viruses that have a high mutation rate) might evade NK cell immunity through the selection of mutations in HLA-presented epitopes that enhance the binding of inhibitory KIRs to HLA class I/peptide complexes. A better understanding of this molecular mechanism for evasion of immune surveillance should facilitate the development of targeted immune interventions (for example, the use of KIR-blocking antibodies, some of which are already being clinically tested for the treatment of cancer) to maximize the antiviral activities of NK cells.
Additional Information
This list of resources contains links that can be accessed when viewing the PDF on a device or via the online version of the article at http://dx.doi.org/10.1371/journal.pmed.1001900.
The US National Institute of Allergy and Infectious Diseases provides a simple description of the human immune system and information on all aspects of HIV infection and AIDS
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS; Avert also provides personal stories about living with HIV/AIDS
The British Society for Immunology provides short articles about various aspects of immunology, including general information about host–pathogen interactions and immune evasion and specific information about HIV and immune evasion
Wikipedia has pages on natural killer cells, KIRs, and HLA molecules (note that Wikipedia is a free online encyclopedia that anyone can edit; available in several languages)
doi:10.1371/journal.pmed.1001900
PMCID: PMC4648589  PMID: 26575988
21.  Afri-Can Forum 2 
Mukudu, Hillary | Martinson, Neil | Sartorius, Benn | Coetzee, Jenny | Dietrich, Janan | Mokgatswana, Kgaugelo | Jewkes, Rachel | Gray, Glenda E. | Dugas, Marylène | Béhanzin, Luc | Guédou, Fernand A. | Gagnon, Marie-Pierre | Alary, Michel | Rutakumwa, Rwamahe | Mbonye, Martin | Kiwanuka, Thadeus | Nakamanya, Sarah | Muhumuza, Richard | Nalukenge, Winfred | Seeley, Janet | Atujuna, Millicent | Wallace, Melissa | Brown, Ben | Bekker, Linda Gail | Newman, Peter A. | Harryparsad, Rushil | Olivier, Abraham J. | Jaspan, Heather B. | Wilson, Douglas | Dietrich, Janan | Martinson, Neil | Mukudu, Hillary | Mkhize, Nonhlanhla | Morris, Lynn | Cianci, Gianguido | Dinh, Minh | Hope, Thomas | Passmore, Jo-Ann S. | Gray, Clive M. | Henrick, Bethany M. | Yao, Xiao-Dan | Rosenthal, Kenneth L. | Henrick, Bethany M. | Yao, Xiao-Dan | Drannik, Anna G. | Abimiku, Alash’le | Rosenthal, Kenneth L. | Chanzu, Nadia | Mwanda, Walter | Oyugi, Julius | Anzala, Omu | Mbow, Moustapha | Jallow, Sabelle | Thiam, Moussa | Davis, Alberta | Diouf, Assane | Ndour, Cheikh T. | Seydi, Moussa | Dieye, Tandakha N. | Mboup, Souleymane | Goodier, Martin | Rilley, Eleanor | Jaye, Assan | Yao, Xiao-Dan | Omange, RW. | Henrick, Bethany M. | Lester, Richard T. | Kimani, Joshua | Ball, T. Blake | Plummer, Francis A. | Rosenthal, Kenneth L. | Béhanzin, Luc | Guédou, Fernand A. | Geraldo, Nassirou | Mastétsé, Ella Goma | Sossa, Jerôme Charles | Zannou, Marcel Djimon | Alary, Michel | Osawe, Sophia | Okpokoro, Evaezi | Okolo, Felicia | Umaru, Stephen | Abimiku, Rebecca | Audu, Sam | Datong, Pam | Abimiku, Alash’le | Nyange, Jacquelyn | Olenja, Joyce | Mutua, Gaudensia | Jaoko, Walter | Omosa-Manyonyi, Gloria | Farah, Bashir | Khaniri, Maureen | Anzala, Omu | Cockcroft, Anne | Tonkin, Kendra | Girish, Indu | Mhati, Puna | Cunningham, Ashley | Andersson, Neil | Farah, Bashir | Indangasi, Jackton | Jaoko, Walter | Mutua, Gaudensia | Khaniri, Maureen | Nyange, Jacquelyn | Anzala, Omu | Diphoko, Thabo | Gaseitsiwe, Simani | Maiswe, Victoria | Iketleng, Thato | Maruapula, Dorcas | Bedi, Keabetswe | Moyo, Sikhulile | Musonda, Rosemary | Wainberg, Mark | Makhema, Joseph | Novitsky, Vladimir | Marlink, Richard | Essex, Max | Okoboi, Stephen | Ssali, Livingstone | Kalibala, Sam | Birungi, Josephine | Egessa, Aggrey | Wangisi, Jonathan | Okullu, Lyavala Joanne | Bakanda, Celestin | Obare, Francis | Boer, I. Marion Sumari-de | Semvua, Hadija H. | van den Boogaard, Jossy | Kiwango, Krisanta W. | Ngowi, Kennedy M. | Nieuwkerk, Pythia T. | Aarnoutse, Rob E. | Kiwelu, Ireen | Muro, Eva | Kibiki, Gibson S. | Datiri, Ruth | Choji, Grace | Osawe, Sophia | Okpokoro, Evaezi | Okolo, Felicia | Umaru, Stephen | Abimiku, Rebecca | Audu, Samuel | Datong, Pam | Abimiku, Alash’le | Fomsgaard, A. | Karlsson, I. | Jensen, K. J. | Jensen, S. S. | Leo-Hansen, C. | Jespersen, S. | Da Silva Té, D. | Rodrigues, C. M. | da Silva, Z. J. | Janitzek, C. M. | Gerstoft, J. | Kronborg, G. | Okpokoro, Evaezi | Osawe, Sophia | Daitiri, Ruth | Choji, Grace | Umaru, Stephen | Okolo, Felicia | Datong, Pam | Abimiku, Alash’le | Emily, Nyariki | Joyce, Olenja | Robert, Lorway R. | Anzala, Anzala | Viljoen, Katie | Wendoh, Jerome | Kidzeru, Elvis | Karaoz, Ulas | Brodie, Eoin | Botha, Gerrit | Mulder, Nicola | Gray, Clive | Cameron, William | Stintzi, Alain | Jaspan, Heather | Levett, Paul N. | Alexander, David | Gulzar, Naveed | Grewal, Prabvir S. | Poon, Art F. Y. | Brumme, Zabrina | Harrigan, P. Richard | Brooks, James I. | Sandstrom, Paul A. | Calvez, Stryker | Sanche, Stephen E. | Scott, Jamie K. | Swartz, Leslie | Kagee, Ashraf | Lesch, Anthea | Kafaar, Zuhayr | De Wet, Anneliese | Okpokoro, Evaezi | Osawe, Sophia | Daitiri, Ruth | Choji, Grace | Umaru, Stephen | Okolo, Felicia | Datong, Pam | Abimiku, Alash’le | Dietrich, Janan | Smith, Tricia | Cotton, Laura | Hornschuh, Stefanie | van der Watt, Martin | Miller, Cari L. | Gray, Glenda | Smit, Jenni | Jaggernath, Manjeetha | Ndung’u, Thumbi | Brockman, Mark | Kaida, Angela | Akolo, Maureen | Kimani, Joshua | Gelmon, Larry | Chitwa, Michael | Osero, Justus | Cockcroft, Anne | Marokoane, Nobantu | Kgakole, Leagajang | Maswabi, Boikhutso | Mpofu, Neo | Ansari, Umaira | Andersson, Neil | Nakinobe, Elizabeth | Miiro, George Mukalazi | Zalwango, Flavia | Nakiyingi-Miiro, Jessica | Kaleebu, Potiano | Semwanga, John Ross | Nyanzi, Emily | Musoke, Saidat Namuli | Nakinobe, Elizabeth | Miiro, George | Mbidde, Edward Katongole | Lutalo, Tom | Kaleebu, Pontiano | Handema, Ray | Chianzu, Graham P. | Thiam, Moussa | Diagne-Gueye, Diabou | Ndiaye, Mame K. | Mbow, Moustapha | Ndiaye, Birahim P. | Traore, Ibrahima | Dia, Mamadou C. | Thomas, Gilleh | Tour-Kane, Coumba | Mboup, Souleymane | Jaye, Assan | Nyanzi, Emily | Mbidde, Edward Katongole | Kaleebu, Pontiano | Mpendo, Juliet | Kimani, Joshua | Birungi, Josephine | Muyindike, Winnie | Kambugu, Andrew | Sebastian, Hachizovu | Ray, Handema | Mike, Chaponda | Bertin, Kabuya Jean | Modest, Mulenga | Thiam, Moussa | Janha, Omar | Davis, Alberta | Amambua-Ngwa, Alfred | Nwakanma, Davis C. | Mboup, Souleymane | Jaye, Assan | Jespersen, Sanne | Hønge, Bo Langhoff | Esbjörnsson, Joakim | Medina, Candida | Da Silva TÉ, David | Correira, Faustino Gomes | Laursen, Alex Lund | Østergaard, Lars | Andersen, Andreas | Aaby, Peter | Erikstrup, Christian | Wejse, Christian | Dieye, Siry | Sarr, Moussa | Sy, Haby | Mbodj, Helene D. | Ndiaye, Marianne | Ndiaye, Amy | Moussa, Seydi | Jaye, Assan | Mboup, Souleymane | Nyombi, Balthazar M. | Shao, Elichilia R. | Chilumba, Innocent B. | Moyo, Sikhulile | Gaseitsiwe, Simani | Musonda, Rosemary | Datong, Pam | Inyang, Bucky | Osawe, Sophia | Izang, Abel | Cole, Chundung | Okolo, Felicia | Cameron, Bill | Rosenthal, Kenneth | Gray, Clive | Jaspan, Heather | Abimiku, Alash’le | Seraise, Boitumelo | Andrea-Marobela, Kerstin | Moyo, Sikhulile | Musonda, Rosemary | Makhema, Joseph | Essex, Max | Gaseitsiwe, Simani
BMC Infectious Diseases  2016;16(Suppl 2):315.
Table of contents
A1 Introduction to the 2nd synchronicity forum of GHRI/CHVI-funded Canadian and African HIV prevention and vaccine teams
O1 Voluntary medical male circumcision for prevention of heterosexual transmission of HIV in adult males in Soweto: What do indicators and incidence rate show?
Hillary Mukudu, Neil Martinson, Benn Sartorius
O2 Developing a peer-led community mobilization program for sex workers in Soweto: HIV risk and demographics
Jenny Coetzee, Janan Dietrich, Kgaugelo Mokgatswana, Rachel Jewkes, Glenda E. Gray
O3 Salient beliefs about adherence: A qualitative survey conducted as part of the demonstration study on "treatment as prevention" (TasP) and "pre-exposure prophylaxis" (PrEP) among female sex workers (FSWS) in Cotonou, Benin
Marylène Dugas, Luc Béhanzin, Fernand A. Guédou, Marie-Pierre Gagnon, Michel Alary
O4 Relative perception of risk as a driver of unsafe sexual practices among key populations: Cases of fisherfolk and women and their partners involved in multiple sexual partnerships in Uganda
Rwamahe Rutakumwa, Martin Mbonye, Thadeus Kiwanuka, Sarah Nakamanya, Richard Muhumuza, Winfred Nalukenge, Janet Seeley
O5 Exploring the acceptability of new biomedical HIV prevention technologies among MSM, adolescents and heterosexual adults in South Africa
Millicent Atujuna, Melissa Wallace, Ben Brown, Linda Gail Bekker, Peter A. Newman
O6 HIV-susceptible target cells in foreskins after voluntary medical male circumcision in South Africa
Rushil Harryparsad, Abraham J. Olivier, Heather B. Jaspan, Douglas Wilson, Janan Dietrich, Neil Martinson, Hillary Mukudu, Nonhlanhla Mkhize, Lynn Morris, Gianguido Cianci, Minh Dinh, Thomas Hope, Jo-Ann S. Passmore, Clive M. Gray
O7 HIV-1 proteins activate innate immune responses via TLR2 heterodimers
Bethany M. Henrick, Xiao-Dan Yao, Kenneth L. Rosenthal, the INFANT Study Team
O8 Characterization of an innate factor in human milk and mechanisms of action against HIV-1
Bethany M. Henrick, Xiao-Dan Yao, Anna G. Drannik, Alash’le Abimiku, Kenneth L. Rosenthal, the INFANT Study Team
O9 Secretor status and susceptibility to HIV infections among female sex workers in Nairobi, Kenya
Nadia Chanzu, Walter Mwanda, Julius Oyugi, Omu Anzala
O10 Natural Killer cell recall responsiveness to Gag-HIV-1 peptides of HIV-1 exposed but uninfected subjects are associated with peripheral CXCR6+ NK cell subsets
Moustapha Mbow, Sabelle Jallow, Moussa Thiam, Alberta Davis, Assane Diouf, Cheikh T. Ndour, Moussa Seydi, Tandakha N. Dieye, Souleymane Mboup, Martin Goodier, Eleanor Rilley, Assan Jaye
O11 Profiles of resistance: Local innate mucosal immunity to HIV-1 in commercial sex workers
Xiao-Dan Yao, RW. Omange, Bethany M. Henrick, Richard T. Lester, Joshua Kimani, T. Blake Ball, Francis A. Plummer, Kenneth L. Rosenthal
O12 Early antiretroviral therapy and pre-exposure prophylaxis for HIV prevention among female sex workers in Cotonou, Benin: A demonstration project
Luc Béhanzin, Fernand A. Guédou, Nassirou Geraldo, Ella Goma Mastétsé, Jerôme Charles Sossa, Marcel Djimon Zannou, Michel Alary
O13 Building capacity for HIV prevention trials: Preliminary data from a Nigerian cohort of HIV exposed sero-negatives (HESN)
Sophia Osawe, Evaezi Okpokoro, Felicia Okolo, Stephen Umaru, Rebecca Abimiku, Sam Audu, Pam Datong, Alash’le Abimiku
O14 Equipping healthcare professionals with skills required for the conduct of clinical trials in an effort to build capacity. Lessons learned
Jacquelyn Nyange, Joyce Olenja, Gaudensia Mutua, Walter Jaoko, Gloria Omosa-Manyonyi, Bashir Farah, Maureen Khaniri, Omu Anzala
O15 Educational technology to support active learning for HIV researchers and planners
Anne Cockcroft, Kendra Tonkin, Indu Girish, Puna Mhati, Ashley Cunningham, Neil Andersson
O16 From Lake Kivu (Rwanda) and Lake Malawi (Tanzania) to the shores of Lake Victoria (Uganda): Strengthening laboratory capacity through Good Clinical Laboratory Practice training
Bashir Farah, Jackton Indangasi, Walter Jaoko, Gaudensia Mutua, Maureen Khaniri, Jacquelyn Nyange, Omu Anzala
O17 Rilpivirine and etravirine resistance mutations in HIV-1 subtype C infected patients on a non-nucleoside reverse transcriptase inhibitor-based combination antiretroviral therapy in Botswana
Thabo Diphoko, Simani Gaseitsiwe, Victoria Maiswe, Thato Iketleng, Dorcas Maruapula, Keabetswe Bedi, Sikhulile Moyo, Rosemary Musonda, Mark Wainberg, Joseph Makhema, Vladimir Novitsky, Richard Marlink, Max Essex
O18 From home-based HIV testing to initiation of treatment: The AIDS Support Organization (TASO) Experience with Home-based HIV Counselling and Testing (HBHCT) among Adolescents in Uganda, 2005-2011
Stephen Okoboi, Livingstone Ssali, Sam Kalibala, Josephine Birungi, Aggrey Egessa, Jonathan Wangisi, Lyavala Joanne Okullu, Celestin Bakanda, Francis Obare41
O19 Feasibility study on using real time medication monitoring among HIV infected and Tuberculosis patients in Kilimanjaro, Tanzania
I. Marion Sumari-de Boer, Hadija H. Semvua, Jossy van den Boogaard, Krisanta W. Kiwango, Kennedy M. Ngowi, Pythia T. Nieuwkerk, Rob E. Aarnoutse, Ireen Kiwelu, Eva Muro, Gibson S. Kibiki
O20 Deaths still among sero-discordant cohort in Nigeria despite Access to treatment
Ruth Datiri, Grace Choji, Sophia Osawe, Evaezi Okpokoro, Felicia Okolo, Stephen Umaru, Rebecca Abimiku, Samuel Audu, Pam Datong, Alash’le Abimiku
O21 Therapeutic HIV-1 vaccine trials in Denmark and Guinea-Bissau
Fomsgaard A, Karlsson I, Jensen KJ, Jensen SS, Leo-Hansen C, Jespersen S, Da Silva Té D, Rodrigues CM, da Silva ZJ, Janitzek CM, Gerstoft J, Kronborg G, the WAPHIR Group
O22 Willingness to participate in a HIV vaccine Trial among HIV exposed sero-negative (HESN) persons in Jos, Nigeria
Evaezi Okpokoro, Sophia Osawe, Ruth Daitiri, Grace Choji, Stephen Umaru, Felicia Okolo, Pam Datong, Alash'le Abimiku
O23 Clinical research volunteers’ perceptions and experiences of screening for enrolment at KAVI-Institute of Clinical Research, Kenya
Nyariki Emily, Olenja Joyce, Lorway R. Robert, Anzala Anzala
O24 Gut microbiome, HIV-exposure, and vaccine responses in South African infants
Katie Viljoen, Jerome Wendoh, Elvis Kidzeru, Ulas Karaoz, Eoin Brodie, Gerrit Botha, Nicola Mulder, Clive Gray, William Cameron, Alain Stintzi, Heather Jaspan, for the INFANT study team
O25 Analysis of HIV pol diversity in the concentrated HIV epidemic in Saskatchewan
Paul N. Levett, David Alexander, Naveed Gulzar, Prabvir S. Grewal, Art F. Y. Poon, Zabrina Brumme, P. Richard Harrigan, James I. Brooks, Paul A. Sandstrom, Stryker Calvez, Stephen E. Sanche, Jamie K. Scott
P1 Evaluating a HIV vaccine research community engagement programme at two HIV prevention research centres in the Western Cape
Leslie Swartz, Ashraf Kagee, Anthea Lesch, Zuhayr Kafaar, Anneliese De Wet
P2 Validating HIV acquisition risk score using a cohort HIV exposed sero-negative persons in a discordant relationship in Jos, Nigeria, West Africa
Evaezi Okpokoro, Sophia Osawe, Ruth Daitiri, Grace Choji, Stephen Umaru, Felicia Okolo, Pam Datong, Alash'le Abimiku
P3 Bridging the gap between adults and adolescents and youth adults (AYA) – Employing a youth-centred approach to investigate HIV risk among AYA in Soweto and Durban, South Africa
Janan Dietrich, Tricia Smith, Laura Cotton, Stefanie Hornschuh, Martin van der Watt, Cari L. Miller, Glenda Gray, Jenni Smit, Manjeetha Jaggernath, Thumbi Ndung’u, Mark Brockman, Angela Kaida, on behalf of the AYAZAZI study teams
P4 Neighbours to sex workers: A key population that has been ignored
Maureen Akolo, Joshua Kimani, Prof Larry Gelmon, Michael Chitwa, Justus Osero
P5 Young women’s access to structural support programmes in a district of Botswana
Anne Cockcroft, Nobantu Marokoane, Leagajang Kgakole, Boikhutso Maswabi, Neo Mpofu, Umaira Ansari, Neil Andersson
P6 Voices for action from peri-urban Ugandan students, teachers and parents on HIV/STI prevention: Qualitative research results
Nakinobe Elizabeth, Miiro George Mukalazi, Zalwango Flavia, Nakiyingi-Miiro Jessica, Kaleebu Potiano
P7 Engaging Social Media as an education tool on the fly: The use of Facebook for HIV and Ebola prevention and awareness amongst adolescents in Uganda
John Ross Semwanga, Emily Nyanzi, Saidat Namuli Musoke, Elizabeth Nakinobe, George Miiro, Edward Katongole Mbidde, Tom Lutalo, Pontiano Kaleebu
P8 Circulating HIV-1 subtypes among sexual minority populations in Zambia
Ray Handema, Graham P. Chianzu
P9 The Development of HIV Bio-bank resource management to support clinical trial and Intervention research: WAPHIR experience
Moussa Thiam, Diabou Diagne-Gueye, Mame K. Ndiaye, Moustapha Mbow, Birahim P. Ndiaye, Ibrahima Traore, Mamadou C. Dia, Gilleh Thomas, Coumba Tour-Kane, Souleymane Mboup, Assan Jaye
P10 Capacity building for clinical trials as a novel approach for scaling up HIV prevention research initiatives in East Africa: achievements and challenges
Emily Nyanzi, Edward Katongole Mbidde, Pontiano Kaleebu, Juliet Mpendo, Joshua Kimani, Josephine Birungi, Winnie Muyindike, Andrew Kambugu
P11 Community and media perspective of research; an advocacy workshop on HIV prevention research
Hachizovu Sebastian, Handema Ray, Chaponda Mike, Kabuya Jean Bertin, Mulenga Modest
P12 Development of a quantitative HIV-1 and HIV-2 real time PCR (qRT-PCR) viral load assay
Moussa Thiam, Omar Janha, Alberta Davis, Alfred Amambua-Ngwa, Davis C. Nwakanma, Souleymane Mboup, Assan Jaye
P13 Differential effects of sex in a West African Cohort of HIV-1, HIV-2 and HIV-1/2 dual infected patients: Men are worse off
Sanne Jespersen, Bo Langhoff Hønge, Joakim Esbjörnsson, Candida Medina, David Da Silva TÉ, Faustino Gomes Correira, Alex Lund Laursen, Lars Østergaard, Andreas Andersen, Peter Aaby, Christian Erikstrup, Christian Wejse, for the Bissau HIV Cohort study group
P14 HIV-infected adolescents in transition from pediatric to adult HIV care in Dakar, Senegal: sample characteristics and immunological and virological profiles
Siry Dieye, Moussa Sarr, Haby Sy, Helene D Mbodj, Marianne Ndiaye, Amy Ndiaye, Seydi Moussa, Assan Jaye, Souleymane Mboup100
P15 Molecular characterization of vertically transmitted HIV-1 among children born to HIV-1 seropositive mothers in Northern Tanzania
Balthazar M. Nyombi, Elichilia R. Shao, Innocent B. Chilumba, Sikhulile Moyo, Simani Gaseitsiwe, Rosemary Musonda
P16 Breast-fed HIV-1 exposed infants play catch up. A preliminary report
Pam Datong, Bucky Inyang, Sophia Osawe, Abel Izang, Chundung Cole, Felicia Okolo, Bill Cameron, Kenneth Rosenthal, Clive Gray, Heather Jaspan, Alash’le Abimiku, the INFANT study team
P17 The frequency of N348I mutation in patient failing combination antiretroviral treatment In Botswana
Boitumelo Seraise, Kerstin Andrea-Marobela, Sikhulile Moyo, Rosemary Musonda, Joseph Makhema, Max Essex, Simani Gaseitsiwe
doi:10.1186/s12879-016-1466-6
PMCID: PMC4943497  PMID: 27410689
22.  HIV-1 Drug Resistance Emergence among Breastfeeding Infants Born to HIV-Infected Mothers during a Single-Arm Trial of Triple-Antiretroviral Prophylaxis for Prevention of Mother-To-Child Transmission: A Secondary Analysis 
PLoS Medicine  2011;8(3):e1000430.
Analysis of a substudy of the Kisumu breastfeeding trial by Clement Zeh and colleagues reveals the emergence of HIV drug resistance in HIV-positive infants born to HIV-infected mothers treated with antiretroviral drugs.
Background
Nevirapine and lamivudine given to mothers are transmitted to infants via breastfeeding in quantities sufficient to have biologic effects on the virus; this may lead to an increased risk of a breastfed infant's development of resistance to maternal antiretrovirals. The Kisumu Breastfeeding Study (KiBS), a single-arm open-label prevention of mother-to-child HIV transmission (PMTCT) trial, assessed the safety and efficacy of zidovudine, lamivudine, and either nevirapine or nelfinavir given to HIV-infected women from 34 wk gestation through 6 mo of breastfeeding. Here, we present findings from a KiBS trial secondary analysis that evaluated the emergence of maternal ARV-associated resistance among 32 HIV-infected breastfed infants.
Methods and Findings
All infants in the cohort were tested for HIV infection using DNA PCR at multiple study visits during the 24 mo of the study, and plasma RNA viral load for all HIV-PCR–positive infants was evaluated retrospectively. Specimens from mothers and infants with viral load >1,000 copies/ml were tested for HIV drug resistance mutations. Overall, 32 infants were HIV infected by 24 mo of age, and of this group, 24 (75%) infants were HIV infected by 6 mo of age. Of the 24 infants infected by 6 mo, nine were born to mothers on a nelfinavir-based regimen, whereas the remaining 15 were born to mothers on a nevirapine-based regimen. All infants were also given single-dose nevirapine within 48 hours of birth. We detected genotypic resistance mutations in none of eight infants who were HIV-PCR positive by 2 wk of age (specimens from six infants were not amplifiable), for 30% (6/20) at 6 wk, 63% (14/22) positive at 14 wk, and 67% (16/24) at 6 mo post partum. Among the 16 infants with resistance mutations by 6 mo post partum, the common mutations were M184V and K103N, conferring resistance to lamivudine and nevirapine, respectively. Genotypic resistance was detected among 9/9 (100%) and 7/15 (47%) infected infants whose mothers were on nelfinavir and nevirapine, respectively. No mutations were detected among the eight infants infected after the breastfeeding period (age 6 mo).
Conclusions
Emergence of HIV drug resistance mutations in HIV-infected infants occurred between 2 wk and 6 mo post partum, most likely because of exposure to maternal ARV drugs through breast milk. Our findings may impact the choice of regimen for ARV treatment of HIV-infected breastfeeding mothers and their infected infants.
Trial Registration
ClinicalTrials.gov NCT00146380
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Globally, more than 2 million children are infected with the human immunodeficiency virus (HIV) that causes acquired immunodeficiency syndrome (AIDS), and half a million children are newly infected every year. These infections are mainly the result of mother-to-child transmission (MTCT) of HIV during pregnancy, labor and delivery, or through breastfeeding. MTCT can be greatly reduced by treating HIV-positive mothers and their babies with antiretroviral drugs (ARVs). Without ARVs, up to half of babies born to HIV-positive mothers become infected with HIV. This rate of transmission falls to below 5% if a combination of three ARVs is given to the mother throughout pregnancy. Unfortunately, this triple-ARV therapy is too expensive for use in the resource-limited countries where most MTCT occurs. Instead, many such countries have introduced simpler, shorter ARV regimens such as a daily dose of zidovudine (a nucleoside reverse transcriptase inhibitor or NRTI) given to HIV-positive women during late pregnancy coupled with single-dose nevirapine (a non-nucleoside reverse transcriptase inhibitor or NNRTI) at the onset of labor, zidovudine and lamivudine (another NRTI) during labor and delivery, and single-dose nevirapine given to the baby at birth.
Why Was This Study Done?
More than 95% of HIV-exposed children are born in resource-limited settings where breastfeeding is the norm and is crucial for child survival even though it poses a risk of HIV transmission. Consequently, several recent studies have investigated whether MTCT can be further reduced by giving the mother ARVs while she is breastfeeding. In the Kisumu Breastfeeding Study (KiBS), for example, researchers assessed the effects of giving zidovudine, lamivudine, and either nevirapine or nelfinavir (a protease inhibitor) to HIV-infected women from 34 weeks of pregnancy through 6 months of breastfeeding. The results of KiBS indicate that this approach might be a safe, feasible way to reduce MTCT (see the accompanying paper by Thomas and colleagues). However, low amounts of nevirapine and lamivudine are transferred from mother to infant in breast milk and this exposure to ARVs could induce the development of resistance to ARVs among HIV-infected infants. In this KiBS substudy, the researchers investigate whether HIV drug resistance emerged in any of the HIV-positive infants in the parent study.
What Did the Researchers Do and Find?
In KiBS, 32 infants were HIV-positive at 24 months old; 24 were HIV-positive at 6 months old when their mothers stopped taking ARVs and when breastfeeding was supposed to stop. The researchers analyzed blood samples taken from these infants at various ages and from their mothers for the presence of HIV drug resistance mutations (DNA changes that make HIV resistant to killing by ARVs). They detected no resistance mutations in samples taken from 2-week old HIV-positive infants or from the infants who became infected after the age of 6 months. However, they found resistance mutations in a third and two-thirds of samples taken from 6-week and 6-month old HIV-positive infants, respectively. The commonest mutations conferred resistance to lamivudine and nevirapine. Moreover, resistance mutations were present in samples taken from all the HIV-positive infants whose mothers who had received nelfinavir but in only half those taken from infants whose mothers who had received nevirapine. Finally, most of the mothers of HIV-positive infants had no HIV drug resistance mutations, and only one mother-infant pair had an overlapping pattern of HIV drug resistance mutations.
What Do These Findings Mean?
These findings indicate that, in this KiBS substudy, the emergence of HIV drug resistance mutations in HIV-infected infants whose mothers were receiving ARVs occurred between 2 weeks and 6 months after birth. The pattern of mutations suggests that drug resistance most likely arose through exposure of the infants to low levels of ARVs in breast milk rather than through MTCT of drug-resistant virus. These findings need confirming but suggest that infants exposed to ARVs through breast milk—a situation that may become increasingly common given the reduction in MTCT seen in KiBS and other similar trials—should be carefully monitored for HIV infection. Providers should consider the mothers' regimen when choosing treatment for infants who are found to be HIV-infected despite maternal triple drug prophylaxis. Infants exposed to a maternal regimen with NNRTI drugs should receive first-line therapy with lopinavir/ritonavir, a protease inhibitor. The significance of the NRTI mutations such as M184V with regard to response to therapy needs further evaluation. The M184V mutation may result in hypersensitization to other NRTI drugs and delay or reverse zidovudine resistance. Given the limited availability of alternative drugs for infants in resource-limited settings, provision of the standard WHO-recommended first-line NRTI backbone, which includes 3TC, with enhanced monitoring of the infant to ensure virologic suppression, could be considered. Such an approach should reduce both illness and morbidity among infants who become HIV positive through breastfeeding.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/ 10.1371/journal.pmed.1000430.
The accompanying PLoS Medicine Research article by Thomas and colleagues describes the primary findings of the Kisumu Breastfeeding Study
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
HIV InSite has comprehensive information on HIV/AIDS
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on children, HIV, and AIDS and on preventing mother-to-child transmission of HIV (in English and Spanish)
UNICEF also has information about children and HIV and AIDS (in several languages)
The World Health organization has information on mother-to-child transmission of HIV (in several languages), and guidance on the use of ARVs for preventing MTCT
doi:10.1371/journal.pmed.1000430
PMCID: PMC3066134  PMID: 21468304
23.  Nevirapine- Versus Lopinavir/Ritonavir-Based Initial Therapy for HIV-1 Infection among Women in Africa: A Randomized Trial 
PLoS Medicine  2012;9(6):e1001236.
In a randomized control trial, Shahin Lockman and colleagues compare nevirapine-based therapy with lopinavir/ritonavir-based therapy for HIV-infected women without previous exposure to antiretroviral treatment.
Background
Nevirapine (NVP) is widely used in antiretroviral treatment (ART) of HIV-1 globally. The primary objective of the AA5208/OCTANE trial was to compare the efficacy of NVP-based versus lopinavir/ritonavir (LPV/r)-based initial ART.
Methods and Findings
In seven African countries (Botswana, Kenya, Malawi, South Africa, Uganda, Zambia, and Zimbabwe), 500 antiretroviral-naïve HIV-infected women with CD4<200 cells/mm3 were enrolled into a two-arm randomized trial to initiate open-label ART with tenofovir (TDF)/emtricitabine (FTC) once/day plus either NVP (n = 249) or LPV/r (n = 251) twice/day, and followed for ≥48 weeks. The primary endpoint was time from randomization to death or confirmed virologic failure ([VF]) (plasma HIV RNA<1 log10 below baseline 12 weeks after treatment initiation, or ≥400 copies/ml at or after 24 weeks), with comparison between treatments based on hazard ratios (HRs) in intention-to-treat analysis. Equivalence of randomized treatments was defined as finding the 95% CI for HR for virological failure or death in the range 0.5 to 2.0. Baseline characteristics were (median): age = 34 years, CD4 = 121 cells/mm3, HIV RNA = 5.2 log10copies/ml. Median follow-up = 118 weeks; 29 (6%) women were lost to follow-up. 42 women (37 VFs, five deaths; 17%) in the NVP and 50 (43 VFs, seven deaths; 20%) in the LPV/r arm reached the primary endpoint (HR 0.85, 95% CI 0.56–1.29). During initial assigned treatment, 14% and 16% of women receiving NVP and LPV/r experienced grade 3/4 signs/symptoms and 26% and 22% experienced grade 3/4 laboratory abnormalities. However, 35 (14%) women discontinued NVP because of adverse events, most in the first 8 weeks, versus none for LPV/r (p<0.001). VF, death, or permanent treatment discontinuation occurred in 80 (32%) of NVP and 54 (22%) of LPV/r arms (HR = 1.7, 95% CI 1.2–2.4), with the difference primarily due to more treatment discontinuation in the NVP arm. 13 (45%) of 29 women tested in the NVP versus six (15%) of 40 in the LPV/r arm had any drug resistance mutation at time of VF.
Conclusions
Initial ART with NVP+TDF/FTC demonstrated equivalent virologic efficacy but higher rates of treatment discontinuation and new drug resistance compared with LPV/r+TDF/FTC in antiretroviral-naïve women with CD4<200 cells/mm3.
Trial registration
ClinicalTrials.gov NCT00089505
Please see later in the article for the Editors' Summary
Editors' Summary
Background
About 34 million people (mostly living in low- or middle-income countries) are currently infected with HIV, the virus that causes AIDS. HIV destroys CD4 lymphocytes and other immune cells, leaving infected individuals susceptible to other infections. Early in the AIDS epidemic, most HIV-infected people died within 10 years of infection. Then, in 1996, antiretroviral therapy (ART)—cocktails of drugs that attack different parts of HIV—became available. For people living in affluent countries, HIV/AIDS became a chronic condition. But, because ART was expensive, for people living in developing countries, HIV/AIDS remained a fatal illness. In 2006, the international community set a target of achieving universal access to ART by 2010 and, although this target has not been reached, by the end of 2010, 6.6 million of the estimated 15 million people in need of ART in developing countries were receiving one of the ART regimens recommended by the World Health Organization (WHO) in its 2010 guidelines.
Why Was This Study Done?
A widely used combination for the initial treatment of HIV-infected people (particularly women) in resource-limited settings is tenofovir and emtricitabine (both nucleotide reverse transcriptase inhibitors; reverse transcriptase is essential for HIV replication) and nevirapine (NVP, a non-nucleoside reverse transcriptase inhibitor). However, little is known about the efficacy of this NVP-based ART combination. Moreover, its efficacy and toxicity has not been compared with regimens containing lopinavir/ritonavir (LPV/r). LPV/r, which inhibits the viral protease that is essential for HIV replication, is available in resource-limited settings but is usually reserved for second-line treatment. LPV/r-based ART is more expensive than NVP-based ART but if it were more effective or better tolerated than NVP-based ART, then first-line treatment with LPV/r-based ART might be cost-effective in resource-limited settings. Conversely, evidence of the clinical equivalence of NVP-based and LPV/r-based ART would provide support for NVP-based ART as an initial therapy. In this randomized equivalence trial, the researchers compare the efficacy and toxicity of NVP-based and LVP/r-based initial therapy for HIV infection among antiretroviral-naïve African women. In a randomized trial, patients are assigned different treatments by the play of chance and followed to compare the effects of these treatments; an equivalence trial asks whether the effects of two treatments are statistically equivalent.
What Did the Researchers Do and Find?
The researchers followed 500 antiretroviral-naïve HIV-infected women with a low CD4 cell count living in seven African countries, half of whom received NVP-based ART and half of whom received LPV/r-based ART, for an average of 118 weeks and recorded the time to virologic failure (the presence of virus in the blood above pre-specified levels) or death among the participants. Forty-two women in the NVP arm reached this primary endpoint (37 virologic failures and five deaths) compared to 50 women in the LPV/r arm (43 virologic failures and seven deaths), a result that indicates equivalent virologic efficacy according to preset statistical criteria. During the initial assigned treatment, similar proportions of women in both treatment arms developed serious drug-related signs and symptoms and laboratory abnormalities. However, whereas 14% of the women in the NVP arm discontinued treatment because of adverse effects, none of the women in the LPV/r arm discontinued treatment. Finally, nearly half of the women tested in the NVP arm but only 15% of the women tested in the LVP/r arm had developed any drug resistance at the time of virologic failure.
What Do These Findings Mean?
These findings indicate that, among HIV-infected, treatment-naïve African women, initial NVP-based ART is as effective as LPV/r-based ART in terms of virologic failure and death although more women in the NVP arm discontinued treatment or developed new drug resistance than in the LPV/r arm. Several limitations of this study may affect the accuracy of these findings. In particular, some of the study participants may have been exposed to single-dose NVP during childbirth to prevent mother-to-child transmission of HIV; in a parallel randomized trial, the researchers found that LPV/r-based ART was superior to NVP-based ART among women with prior exposure to single-dose NVP. Moreover, the duration of the current study means the long-term effects of the two treatments cannot be compared. Nevertheless, these findings support the WHO recommendation of NVP-based ART with careful early toxicity monitoring as an initial affordable and effective HIV treatment regiment in resource-limited settings, until access to better-tolerated and more potent regimens is possible.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001236.
Information is available from the US National Institute of Allergy and Infectious Diseases on all aspects of HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS, and summaries of recent research findings on HIV care and treatment (in several languages)
Information is available from Avert, an international AIDS charity on many aspects of HIV/AIDS, including detailed information on HIV treatment and care (in English and Spanish)
WHO provides information about universal access to AIDS treatment (in English, French and Spanish); its 2010 ART guidelines can be downloaded
More information about this trial, the OCTANE trial, is available
MedlinePlus provides detailed information about nevirapine and lopinavir/ritinovir (in English and Spanish)
Patient stories about living with HIV/AIDS are available through Avert; the nonprofit website Healthtalkonline also provides personal stories about living with HIV, including stories about taking anti-HIV drugs and the challenges of anti-HIV drugs
doi:10.1371/journal.pmed.1001236
PMCID: PMC3373629  PMID: 22719231
24.  HIV among People Who Inject Drugs in the Middle East and North Africa: Systematic Review and Data Synthesis 
PLoS Medicine  2014;11(6):e1001663.
Laith Abu-Raddad and colleagues assess the current state of knowledge of the HIV epidemic among people who inject drugs in the Middle East and North Africa.
Please see later in the article for the Editors' Summary
Background
It is perceived that little is known about the epidemiology of HIV infection among people who inject drugs (PWID) in the Middle East and North Africa (MENA). The primary objective of this study was to assess the status of the HIV epidemic among PWID in MENA by describing HIV prevalence and incidence. Secondary objectives were to describe the risk behavior environment and the HIV epidemic potential among PWID, and to estimate the prevalence of injecting drug use in MENA.
Methods and Findings
This was a systematic review following the PRISMA guidelines and covering 23 MENA countries. PubMed, Embase, regional and international databases, as well as country-level reports were searched up to December 16, 2013. Primary studies reporting (1) the prevalence/incidence of HIV, other sexually transmitted infections, or hepatitis C virus (HCV) among PWIDs; or (2) the prevalence of injecting or sexual risk behaviors, or HIV knowledge among PWID; or (3) the number/proportion of PWID in MENA countries, were eligible for inclusion. The quality, quantity, and geographic coverage of the data were assessed at country level. Risk of bias in predefined quality domains was described to assess the quality of available HIV prevalence measures. After multiple level screening, 192 eligible reports were included in the review. There were 197 HIV prevalence measures on a total of 58,241 PWID extracted from reports, and an additional 226 HIV prevalence measures extracted from the databases.
We estimated that there are 626,000 PWID in MENA (range: 335,000–1,635,000, prevalence of 0.24 per 100 adults). We found evidence of HIV epidemics among PWID in at least one-third of MENA countries, most of which are emerging concentrated epidemics and with HIV prevalence overall in the range of 10%–15%. Some of the epidemics have however already reached considerable levels including some of the highest HIV prevalence among PWID globally (87.1% in Tripoli, Libya). The relatively high prevalence of sharing needles/syringes (18%–28% in the last injection), the low levels of condom use (20%–54% ever condom use), the high levels of having sex with sex workers and of men having sex with men (15%–30% and 2%–10% in the last year, respectively), and of selling sex (5%–29% in the last year), indicate a high injecting and sexual risk environment. The prevalence of HCV (31%–64%) and of sexually transmitted infections suggest high levels of risk behavior indicative of the potential for more and larger HIV epidemics.
Conclusions
Our study identified a large volume of HIV-related biological and behavioral data among PWID in the MENA region. The coverage and quality of the data varied between countries. There is robust evidence for HIV epidemics among PWID in multiple countries, most of which have emerged within the last decade and continue to grow. The lack of sufficient evidence in some MENA countries does not preclude the possibility of hidden epidemics among PWID in these settings. With the HIV epidemic among PWID in overall a relatively early phase, there is a window of opportunity for prevention that should not be missed through the provision of comprehensive programs, including scale-up of harm reduction services and expansion of surveillance systems.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
About 35 million people worldwide are currently infected with HIV, the virus that causes AIDS, and around 2.3 million people become newly infected every year. HIV is mainly transmitted through unprotected sex with an infected partner. However, people who inject drugs (PWID) have a particularly high risk of HIV infection because blood transfer through needle and syringe sharing can transmit the virus. Worldwide, 5%–10% of all HIV-positive people are PWID but in some regions of the world the fraction of all HIV-positive people that are PWID is even higher. To meet the global health challenge of the high HIV prevalence (the proportion of a population that has a specific disease) among PWID, the Joint United Nations Programme on HIV/AIDS (UNAIDS) and other international bodies endorse harm reduction strategies to prevent risky injection behaviors among PWID. These strategies include education and the provision of clean needles, syringes, and opioid substitution therapy.
Why Was This Study Done?
To maximize the effect of these harm-reduction strategies in specific regions, it is important to understand the status of the HIV epidemic among PWID. Although surveillance systems provide the information on HIV infection needed to track the progress of HIV epidemics among PWID in many regions, little is known about the HIV epidemic among PWID in the Middle East and North Africa (MENA, a geographical region that encompasses countries that share historical, socio-cultural, linguistic, and religious characteristics). Several factors contribute to the likelihood of individuals injecting drugs in MENA. For example, Afghanistan (a MENA country) produces most of the world's supply of heroin, which is largely trafficked through Iran and Pakistan (also MENA countries). In this systematic review and data synthesis, the researchers use predefined criteria to identify all the published and unpublished data on HIV prevalence and incidence (the number of new cases of a disease in a population in a given time) among PWID in MENA and combine (synthesize) these data to assess the status of the HIV epidemic in this key population for HIV transmission in MENA.
What Did the Researchers Do and Find?
The researchers identified 192 reports that reported the prevalence/incidence of HIV, other sexually transmitted infections and infection with hepatitis C virus (HCV, another virus transmitted through drug injection) among PWID, the prevalence of injecting or sexual risk behaviors among PWID, or the number/proportion of PWID in MENA. From these data, the researchers estimated that there are about 600,000 PWID in MENA (a prevalence of 0.24 per 100 adults, which is comparable with figures from other regions). The data provided evidence for HIV epidemics among PWID in at least a third of MENA countries, mainly emerging concentrated epidemics (epidemics that are still growing but in which HIV infection and transmission are already considerable). HIV prevalence among PWID in MENA varied considerably, reaching an extremely high prevalence of 87.1% in Tripoli, Libya. The data also revealed a high injecting and sexual risk environment among PWID in MENA (for example, on average, about a quarter of PWID shared a needle or syringe in their most recent injection and only a third reported ever using condoms) that, together with a high prevalence of HCV and sexually transmitted infections among PWID, indicates the potential for more and larger HIV epidemics.
What Do These Findings Mean?
These findings indicate that substantial amounts of HIV-related data have been collected from PWID in MENA but that the coverage and quality of these data vary widely between countries. They provide robust evidence for growing HIV epidemics, most of which have emerged within the past decade, among PWID in several MENA countries, but do not preclude the possibility of hidden epidemics among PWID in additional MENA countries. Overall, these findings suggest that the HIV epidemic among PWID in MENA is at a relatively early stage. This window of opportunity to control the emerging epidemics should not be missed, warn the researchers. HIV surveillance among PWID in MENA must be expanded to detect and monitor emerging and growing HIV epidemics, they suggest, and to inform effective HIV policy and programming. Improvements in HIV prevention and treatment among PWID in MENA are essential, they conclude, to confront the growing HIV problem in this population and, to prevent the onward transmission of HIV from PWID to other population groups.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001663.
A 2010 report produced by the World Bank, UNAIDS, and WHO provides information on the status of the HIV epidemic in the Middle East and North Africa; the UNAIDS Middle East and North Africa Regional Report on AIDS 2011 provides further information
The 2013 UNAIDS World AIDS Day Report provides up-to-date information about the AIDS epidemic and efforts to halt it
The Middle East and North Africa Harm Reduction Association (MENAHRA) provides information about harm reduction efforts, services, and programs in the Middle East and North Africa; Harm Reduction International provides information about harm reduction concepts, strategies, programs, and publications globally
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS, and summaries of recent research findings on HIV care and treatment
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on people who inject drugs and HIV/AIDS and on harm reduction and HIV prevention (in English and Spanish)
The US National Institute on Drug Abuse also provides information about drug abuse and HIV/AIDS (in English and Spanish)
Personal stories about living with HIV/AIDS are available through Avert, Nam/aidsmap, and Healthtalkonline
doi:10.1371/journal.pmed.1001663
PMCID: PMC4061009  PMID: 24937136
25.  The Infectiousness of Tuberculosis Patients Coinfected with HIV 
PLoS Medicine  2008;5(9):e188.
Background
The current understanding of airborne tuberculosis (TB) transmission is based on classic 1950s studies in which guinea pigs were exposed to air from a tuberculosis ward. Recently we recreated this model in Lima, Perú, and in this paper we report the use of molecular fingerprinting to investigate patient infectiousness in the current era of HIV infection and multidrug-resistant (MDR) TB.
Methods and Findings
All air from a mechanically ventilated negative-pressure HIV-TB ward was exhausted over guinea pigs housed in an airborne transmission study facility on the roof. Animals had monthly tuberculin skin tests, and positive reactors were removed for autopsy and organ culture for M. tuberculosis. Temporal exposure patterns, drug susceptibility testing, and DNA fingerprinting of patient and animal TB strains defined infectious TB patients. Relative patient infectiousness was calculated using the Wells-Riley model of airborne infection. Over 505 study days there were 118 ward admissions of 97 HIV-positive pulmonary TB patients. Of 292 exposed guinea pigs, 144 had evidence of TB disease; a further 30 were tuberculin skin test positive only. There was marked variability in patient infectiousness; only 8.5% of 118 ward admissions by TB patients were shown by DNA fingerprinting to have caused 98% of the 125 characterised cases of secondary animal TB. 90% of TB transmission occurred from inadequately treated MDR TB patients. Three highly infectious MDR TB patients produced 226, 52, and 40 airborne infectious units (quanta) per hour.
Conclusions
A small number of inadequately treated MDR TB patients coinfected with HIV were responsible for almost all TB transmission, and some patients were highly infectious. This result highlights the importance of rapid TB drug-susceptibility testing to allow prompt initiation of effective treatment, and environmental control measures to reduce ongoing TB transmission in crowded health care settings. TB infection control must be prioritized in order to prevent health care facilities from disseminating the drug-resistant TB that they are attempting to treat.
Using a guinea pig detection system above an HIV-tuberculosis ward, Rod Escombe and colleagues found that most transmitted tuberculosis originated from patients with inadequately treated multidrug-resistant tuberculosis.
Editors' Summary
Background.
Every year, more than nine million people develop tuberculosis—a contagious infection usually of the lungs—and nearly two million people die from the disease. Tuberculosis is caused by Mycobacterium tuberculosis. These bacteria are spread in airborne droplets when people with the disease cough or sneeze. Most people infected with M. tuberculosis never become ill—their immune system contains the infection. However, the bacteria remain dormant within the body and can cause tuberculosis years later if host immunity declines. The symptoms of tuberculosis include a persistent cough, weight loss, and night sweats. Diagnostic tests for the disease include chest X-rays, the tuberculin skin test, and sputum cultures (in which bacteriologists try to grow M. tuberculosis from mucus brought up from the lungs by coughing). Tuberculosis can usually be cured by taking several powerful antibiotics daily for several months.
Why Was This Study Done?
Scientists performed definitive experiments on airborne tuberculosis transmission in the 1950s by exposing guinea pigs to the air from a tuberculosis ward. They found that a minority of patients actually transmit tuberculosis, that the infectiousness of transmitters varies greatly, and that effective antibiotic treatment decreases infectiousness. Since the 1950s, however, multidrug-resistant (MDR) and more recently extensively drug-resistant (XDR) strains of M. tuberculosis have become widespread. Treatment of drug-resistant tuberculosis is much more difficult than normal tuberculosis, requiring even more antibiotics, and for long periods, up to 2 years and beyond. In addition, HIV (the virus that causes AIDS) has emerged. HIV weakens the immune system so HIV-positive people are much more likely to develop active tuberculosis (and to die from the disease, which also speeds the development of HIV/AIDS) than people with a healthy immune system. Have these changes altered tuberculosis transmission between people? The answer to this question might help to optimize the control of tuberculosis infection, particularly in hospitals. In this study, the researchers investigate current patterns of tuberculosis infectiousness among HIV-positive patients by recreating the 1950s guinea pig model for tuberculosis transmission in a hospital in Lima, Perú.
What Did the Researchers Do and Find?
The researchers passed all the air from an HIV–tuberculosis ward over guinea pigs housed in an animal facility on the hospital's roof. The guinea pigs were tested monthly with tuberculin skin tests, and tissues from positive animals were examined for infection with M. tuberculosis. Sputum was also collected daily from the patients on the ward. The researchers then used the timing of patient admissions and guinea pig infections, together with the drug susceptibility patterns and DNA fingerprints of the M. tuberculosis strains isolated from the animals and the patients, to identify which patients had infected which guinea pigs. Finally, they used a mathematical equation to calculate the relative infectiousness of each patient in airborne infectious units (“quanta”) per hour. During the 505 study days, although 97 HIV-positive patients with tuberculosis were admitted to the ward, just ten patients were responsible for virtually all the characterized cases of tuberculosis among the guinea pigs. Six of these patients had MDR tuberculosis that had been suboptimally treated. The average patient infectiousness over the entire study period was 8.2 quanta per hour—six times greater than the average infectiousness recorded in the 1950s. Finally, the three most infectious patients (all of whom had suboptimally treated MDR tuberculosis) produced 226, 52, and 40 quanta per hour.
What Do These Findings Mean?
These findings show that a few inadequately treated HIV-positive patients with MDR tuberculosis caused nearly all the tuberculosis transmission to guinea pigs during this study. They also show for the first time that tuberculosis infectiousness among HIV-positive patients is very variable. The increase in the average patient infectiousness in this study compared to that seen in the 1950s hints at the possibility that HIV infection might increase tuberculosis infectiousness. However, studies that directly compare the tuberculosis infectiousness of HIV-positive and HIV-negative patients are needed to test this possibility. More importantly, this study demonstrates the potentially high infectiousness of inadequately treated MDR TB patients and their importance in ongoing TB transmission. These findings suggest that rapid, routine testing of antibiotic susceptibility should improve tuberculosis control by ensuring that patients with MDR TB are identified and treated effectively and quickly. Finally, they re-emphasize the importance of implementing environmental control measures (for example, adequate natural or mechanical ventilation of tuberculosis wards, or crowded waiting rooms or emergency departments where tuberculosis patients may be found) to prevent airborne tuberculosis transmission in health-care facilities, particularly in areas where many patients are HIV positive and/or where MDR tuberculosis is common.
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0050188.
The US National Institute of Allergy and Infectious Diseases provides information on all aspects of tuberculosis, including multidrug-resistance tuberculosis, and on tuberculosis and HIV
The US Centers for Disease Control and Prevention provide several fact sheets and other information resources about all aspects of tuberculosis (in English and Spanish)
The World Health Organization's 2008 report on global tuberculosis control—surveillance, planning, financing provides a snapshot of the current state of the global tuberculosis epidemic and links to information about all aspects of tuberculosis and its control (in several languages)
HIVInsite provides detailed information about coinfection with HIV and tuberculosis
• Avert, an international AIDS charity, also provides information about the interaction between HIV and tuberculosis
Tuberculosis Infection-Control in the Era of Expanding HIV Care and Treatment is a report from the World Health Organization
doi:10.1371/journal.pmed.0050188
PMCID: PMC2535657  PMID: 18798687

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