CCR5 is the primary coreceptor for HIV entry. Early after infection, the HIV viral population diversifies rapidly into a quasispecies. It is not known whether the initial efficiency of the viral quasispecies to utilize CCR5 is associated with HIV disease progression or if it changes in an infected individual over time. The CCR5 and CXCR4 utilization efficiencies (R5-UE and X4-UE) of the HIV quasispecies were examined using a pseudovirus, single-round infection assay for samples obtained from known seroconverters from Rakai district, Uganda (n=88). Initial and longitudinal R5-UE values were examined to assess the association of R5-UE with HIV disease progression using multivariate Cox proportional hazard models. Longitudinal samples were analyzed for 35 seroconverters who had samples available from multiple time points. There was no association between initial or longitudinal changes in R5-UE and the hazard of HIV disease progression (p=0.225 and p=0.942, respectively). In addition, R5-UE increased significantly over time after HIV seroconversion (p<0.001), regardless of HIV subtype or the emergence of CXCR4-tropic virus. These data demonstrate that the R5-UE of the viral quasispecies early in HIV infection is not associated with disease progression, and that R5-UE levels increase in HIV-infected individuals over time.
The Post-exposure Prophylaxis in Infants (PEPI)-Malawi trial evaluated infant antiretroviral regimens for prevention of post-natal HIV transmission. A multi-assay algorithm (MAA) that includes the BED capture immunoassay, an avidity assay, CD4 cell count, and viral load was used to identify women who were vs. were not recently infected at the time of enrollment (MAA recent, N = 73; MAA non-recent, N = 2,488); a subset of the women in the MAA non-recent group known to have been HIV infected for at least 2 years before enrollment (known non-recent, N = 54). Antibody maturation and viral diversification were examined in these women.
Samples collected at enrollment (N = 2,561) and 12–24 months later (N = 1,306) were available for serologic analysis using the BED and avidity assays. A subset of those samples was used for analysis of viral diversity, which was performed using a high resolution melting (HRM) diversity assay. Viral diversity analysis was performed using all available samples from women in the MAA recent group (61 enrollment samples, 38 follow-up samples) and the known non-recent group (43 enrollment samples, 22 follow-up samples). Diversity data from PEPI-Malawi were also compared to similar data from 169 adults in the United States (US) with known recent infection (N = 102) and known non-recent infection (N = 67).
In PEPI-Malawi, results from the BED and avidity assays increased over time in the MAA recent group, but did not change significantly in the MAA non-recent group. At enrollment, HIV diversity was lower in the MAA recent group than in the known non-recent group. HRM diversity assay results from women in PEPI-Malawi were similar to those from adults in the US with known duration of HIV infection.
Antibody maturation and HIV diversification patterns in African women provide additional support for use of the MAA to identify populations with recent HIV infection.
Viral suppression and viral breakthrough impact the humoral immune response to HIV infection. We evaluated the impact of viral suppression and viral breakthrough on results obtained with two cross-sectional HIV incidence assays.
All samples were collected from adults in the US who were HIV infected for >2 years. Samples were tested with the BED capture enzyme immunoassay (BED-CEIA) which measures the proportion of IgG that is HIV-specific, and with an antibody avidity assay based on the Genetic Systems 1/2+ O ELISA. We tested 281 samples: (1) 30 samples from 18 patients with natural control of HIV-1 infection known as elite controllers or suppressors (2) 72 samples from 18 adults on antiretroviral therapy (ART), with 1 sample before and 2–6 samples after ART initiation, and (3) 179 samples from 20 virally-suppressed adults who had evidence of viral breakthrough receiving ART (>400 copies/ml HIV RNA) and with subsequent viral suppression.
For elite suppressors, 10/18 had BED-CEIA values <0.8 normalized optical density units (OD-n) and these values did not change significantly over time. For patients receiving ART, 14/18 had BED-CEIA values that decreased over time, with a median decrease of 0.42 OD-n (range 0.10 to 0.63)/time point receiving ART. Three patterns of BED-CEIA values were observed during viral breakthrough: (1) values that increased then returned to pre-breakthrough values when viral suppression was re-established, (2) values that increased after viral breakthrough, and (3) values that did not change with viral breakthrough.
Viral suppression and viral breakthrough were associated with changes in BED-CEIA values, reflecting changes in the proportion of HIV-specific IgG. These changes can result in misclassification of patients with long-term HIV infection as recently infected using the BED-CEIA, thereby influencing a falsely high value for cross-sectional incidence estimates.
Recent studies suggest HIV-1 inter-subtype differences in co-receptor usage. We examined the correlation between HIV-1 subtype and co-receptor usage among treatment-naïve HIV-1 subjects in Singapore. Additionally, we investigated whether the subtype co-receptor association was influenced by stage of infection.
V3 sequences of HIV-1 envelope protein gp120 were obtained from 110 HIV treatment-naïve patients and genotypic co-receptor tropism determination was performed using Geno2pheno. Two false-positive rate (FPR) cut-offs, 10% and 5.75% were selected for tropism testing.
Subtype assignment of viral strains from 110 HIV-infected individuals based on partial sequencing of HIV-1 pol, gp120 and gp41 were as follows: 27 subtype B, 64 CRF01_AE, 10 CRF51_01B, and 9 other subtypes. At FPR=10%, 10 (100%) CRF51_01B-infected subjects and 26 (40.6%) CRF01_AE-infected subjects had CXCR4-using virus, compared to 7 (25.9%) subtype B subjects and 1 (11.1%) CRF33_01B-infected subject (P < 0.001). At FPR=5.75%, 10 (100%) CRF51_01B-infected subjects and 20 (31.3%) CRF01_AE-infected subjects had CXCR4-using virus, compared to 4 (14.8%) subtype B and 1 (11.1%) CRF33_01B-infected subjects (P < 0.001). Among those with evidence of seroconversion within 2 years prior to study enrolment, 100% of CRF51_01B-infected subjects had CXCR4-using virus, independent of Geno2pheno FPR.
CRF51_01B and CRF01_AE-infected individuals have higher prevalence of CXCR4-usage compared to subtype B infected individuals. Further studies examining these differences could help optimise the use of CCR5-antagonist in populations with these subtypes, and increase our understanding of HIV-1 biology.
CXCR4 usage; HIV-1; treatment-naïve
To investigate HIV-1 molecular epidemiology in Singapore, we sequenced portions of three regions of the HIV-1 genome (protease HXB2: 2163 to 2620, gp120 HXB2: 6904 to 7628, and gp41 HXB2: 7817 to 8264) from 212 plasma samples collected between February 2008 and August 2009. From these samples, 109 (51.4%) generated interpretable data in all regions. Sixty-one (56.0%) were identified as CRF01_AE, 26 (23.9%) as subtype B and 14 (12.8%) as possible novel recombinant forms. The main novel recombinant pattern, detected in 13 sequences, had subtype B in protease and gp41 and CRF01_AE in gp120. There was intermixing of subtypes within transmission risk groups. However, 85% of subjects infected with the novel recombinant forms self-identified as men who have sex with men or bisexuals compared with only 41% of individuals infected with CRF01_AE and 62% infected with subtype B (p = 0.001).
We previously developed a multi-assay algorithm (MAA) to identify recent HIV infection that includes the BED-Capture Enzyme Immunoassay, an avidity assay based on the Genetic Systems HIV-1/HIV-2+O Enzyme Immunoassay, CD4 cell count, and HIV viral load. We used this MAA to evaluate the association between recent maternal HIV infection and in utero transmission of HIV.
Plasma samples were collected at delivery from 2,561 HIV-infected women in the PEPI-Malawi trial. The MAA described above was used to identify women with recent HIV infection. Logistic regression models assessed association between recent HIV infection and in utero HIV transmission (defined as a positive infant HIV DNA test at birth).
Seventy-three women were identified as recently infected using the MAA. Those women were younger and had lower parity than women who were identified as not recently infected using the MAA (P<0.0001 for age and parity). The frequency of in utero HIV transmission was 17.8% among women identified as recently infected, compared to 6.7% among women identified as not recently infected (13/73 vs. 166/2488, P=0.001). In a multivariate model, three factors were independently associated with in utero HIV transmission: recent infection (adjusted odds ratio [AOR]: 2.49, 95% CI: 1.30–4.78, P=0.006), log10 HIV viral load at delivery (AOR: 2.01, 95% CI: 1.60–2.51, P<0.0001), and younger age (per 10 year increase, AOR: 0.66, 95% CI: 0.43–0.93, P=0.02).
Results obtained using a MAA suggest that recent maternal HIV acquisition is strongly associated with in utero HIV transmission, independent of HIV viral load at delivery.
HIV; incidence; multiassay algorithm; mother-to-child transmission; Malawi
Herpes simplex virus type 2 (HSV-2) infection is one of the most commonly sexually transmitted infections worldwide. While glycoprotein G-2 ELISA based assays are commonly used for the serologic detection of HSV-2 infections, they have low specificity in developing countries. Euroline Western blot (WB) is a commercially available assay that is easy to perform; however, little is known about its performance characteristics. This study evaluated Euroline WB for the detection of HSV-2 antibodies compared to University of Washington Western blot in three geographically different regions, Baltimore, Maryland, Rakai, Uganda, and Kunming, China. Among the 135 American men attending an STD clinic in Baltimore, Maryland, 72% (n=97) were HSV-2 positive by Euroline WB. The Euroline WB had a sensitivity of 97.8% and a specificity of 81.8%. Among the 273 commercial sex workers in Kunming, 62.3% were HSV-2 positive by Euroline WB. The Euroline WB had a sensitivity of 96.9% and a specificity of 89.1%. Among the 437 Ugandans in Rakai, 67.3% were HSV-2 positive by Euroline WB. The Euroline WB had a sensitivity of 98.7% and a specificity of 65.4%. The Euroline WB has a consistently high sensitivity, but specificity varied significantly among the different locations.
HIV superinfection, which occurs when a previously infected individual acquires a new distinct HIV strain, has been described in a number of populations. Previous methods to detect superinfection have involved a combination of labor-intensive assays with various rates of success. We designed and tested a next-generation sequencing (NGS) protocol to identify HIV superinfection by targeting two regions of the HIV viral genome, p24 and gp41. The method was validated by mixing control samples infected with HIV subtype A or D at different ratios to determine the inter- and intrasubtype sensitivity by NGS. This amplicon-based NGS protocol was able to consistently identify distinct intersubtype strains at ratios of 1% and intrasubtype variants at ratios of 5%. By using stored samples from the Rakai Community Cohort Study (RCCS) in Uganda, 11 individuals who were HIV seroconcordant but virally unlinked from their spouses were then tested by this method to detect superinfection between 2002 and 2005. Two female cases of HIV intersubtype superinfection (18.2%) were identified. These results are consistent with other African studies and support the hypothesis that HIV superinfection occurs at a relatively high rate. Our results indicate that NGS can be used for detection of HIV superinfection within large cohorts, which could assist in determining the incidence and the epidemiologic, virologic, and immunological correlates of this phenomenon.
HIV and hepatitis B virus (HBV) co-infection poses important public health considerations in resource-limited settings. Demographic data and sera from adult participants of the Rakai Health Sciences Program Cohort in Southwestern Uganda were examined to determine HBV seroprevalence patterns in this area of high HIV endemicity prior to the introduction of antiretroviral therapy. Commercially available EIAs were used to detect prevalent HBV infection (positive for HBV core antibody [anti-HBc] and/or positive HBV surface antigen [HBsAg]), and chronic infection (positive for HBsAg). Of 438 participants, 181 (41%) had prevalent HBV infection while 21 (5%) were infected chronically. Fourteen percent of participants were infected with HIV. Fifty three percent showed evidence of prevalent HBV infection compared to 40% among participants infected with HIV (p=0.067). Seven percent of participants infected with HIV were HBsAg positive compared to 4% among participants not infected with HIV (p=0.403). The prevalence of prevalent HBV infection was 55% in adults aged >50 years old, and 11% in persons under 20 years. In multivariable analysis, older age, HIV status and serologic syphilis were significantly associated with prevalent HBV infection. Transfusion status and receipt of injections were not significantly associated with HBV infection. Contrary to expectations that HBV exposure in Uganda occurred chiefly during childhood, prevalent HBV infection was found to increase with age and was associated sexually transmitted diseases (HIV and syphilis.) Therefore vaccination against HBV, particularly susceptible adults with HIV or at risk of HIV/STDs should be a priority.
Hepatitis B virus HBV; HIV; Sexual transmission; Uganda; Africa
Cross-sectional assessment of HIV incidence relies on laboratory methods to discriminate between recent and non-recent HIV infection. Because HIV diversifies over time in infected individuals, HIV diversity may serve as a biomarker for assessing HIV incidence. We used a high resolution melting (HRM) diversity assay to compare HIV diversity in adults with different stages of HIV infection. This assay provides a single numeric HRM score that reflects the level of genetic diversity of HIV in a sample from an infected individual.
HIV diversity was measured in 203 adults: 20 with acute HIV infection (RNA positive, antibody negative), 116 with recent HIV infection (tested a median of 189 days after a previous negative HIV test, range 14–540 days), and 67 with non-recent HIV infection (HIV infected >2 years). HRM scores were generated for two regions in gag, one region in pol, and three regions in env.
Median HRM scores were higher in non-recent infection than in recent infection for all six regions tested. In multivariate models, higher HRM scores in three of the six regions were independently associated with non-recent HIV infection.
The HRM diversity assay provides a simple, scalable method for measuring HIV diversity. HRM scores, which reflect the genetic diversity in a viral population, may be useful biomarkers for evaluation of HIV incidence, particularly if multiple regions of the HIV genome are examined.
To determine if mishandling prior to testing would make a sample from a chronically infected subject appear recently infected when tested by cross-sectional HIV incidence assays.
Serum samples from 31 subjects with chronic HIV infection were tested. Samples were subjected to different handling conditions, including incubation at 4°C, 25°C and 37°C, for 1, 3, 7 or 15 days prior to testing. Samples were also subjected to 1,3, 7 and 15 freeze-thaw cycles prior to testing. Samples were tested using the BED capture enzyme immuno assay (BED-CEIA), Vironostika-less sensitive (V-LS), and an avidity assay using the Genetic Systems HIV-1/HIV-2 plus O EIA (avidity assay).
Compared to the sample that was not subjected to any mishandling conditions, for the BED-CEIA, V-LS and avidity assay, there was no significant change in test results for samples incubated at 4°C or 25°C prior to testing. No impact on test results occurred after 15 freeze-thaw cycles. A decrease in assay results was observed when samples were held for 3 days or longer at 37°C prior to testing.
Samples can be subjected up to 15 freeze-thaw cycles without affecting the results the BED-CEIA, Vironostika-LS, or avidity assays. Storing samples at 4°C or 25°C for up to fifteen days prior to testing had no impact on test results. However, storing samples at 37°C for three or more days did affect results obtained with these assays.
Recent data shows that HIV-1 is characterised by variation in viral virulence factors that is heritable between infections, which suggests that viral virulence can be naturally selected at the population level. A trade-off between transmissibility and duration of infection appears to favour viruses of intermediate virulence. We developed a mathematical model to simulate the dynamics of putative viral genotypes that differ in their virulence. As a proxy for virulence, we use set-point viral load (SPVL), which is the steady density of viral particles in blood during asymptomatic infection. Mutation, the dependency of survival and transmissibility on SPVL, and host effects were incorporated into the model. The model was fitted to data to estimate unknown parameters, and was found to fit existing data well. The maximum likelihood estimates of the parameters produced a model in which SPVL converged from any initial conditions to observed values within 100–150 years of first emergence of HIV-1. We estimated the 1) host effect and 2) the extent to which the viral virulence genotype mutates from one infection to the next, and found a trade-off between these two parameters in explaining the variation in SPVL. The model confirms that evolution of virulence towards intermediate levels is sufficiently rapid for it to have happened in the early stages of the HIV epidemic, and confirms that existing viral loads are nearly optimal given the assumed constraints on evolution. The model provides a useful framework under which to examine the future evolution of HIV-1 virulence.
Recent studies have suggested that virulence in HIV-1 is partly a characteristic of the virus which is carried from one infection to the next. An infection with intermediate virulence will produce more transmissions during the infectious lifetime because it optimises the trade-off between rate of transmission and duration of infection. Natural selection acts on the heritable variation to increase the relative prevalence of strains with intermediate virulence. In this study we model the evolution of virulence in the viral population as these more successful strains are preferentially transmitted. We fit this model to data from transmitting couples, and find that the model fits the data well. We use this fit to estimate the contribution of the host and the virus to virulence, which complements recent estimates of the heritability of virulence. We also estimate the rate at which the viral determinants of virulence evolve between infections, and this provides predictions for how rapidly the virulence of HIV-1 evolves in a population. We suggest that natural selection on transmissibility results in substantial evolution of virulence in the population. This is sufficiently rapid for virulence to have reached current levels over the available timescale of the human epidemic.
HIV-1 subtype D (HIV-1D) progresses to disease faster and has lower transmissibility than subtype A (HIV-1A). We examined whether these differences could lead to a population level change in the distribution of these subtypes over time. HIV-1 viral RNA was extracted from stored serum samples from HIV-positive subjects participating in a population-based cohort study in Rakai, Uganda in 1994 and 2002. Portions of the viral proteins gag and gp41 were sequenced and subtyped. HIV-1 subtype assignments were generated for 773 subjects in 1994 and 812 subjects in 2002. The change in subtype distribution of the population as a whole as well as quartile age groups were examined for significant changes using a linear model. There was a significant decrease in the proportion of subjects infected with HIV-1D from 70.2% to 62.4% and a significant increase in subjects infected with HIV-1A from 16.7% to 23.3% over the 8-year period (p = 0.005). The most marked changes in proportion of HIV-1D and A were seen in the younger individuals (<25 and 25–30 years; p < 0.05). The percentages of subjects infected with HIV-1C and recombinant subtypes did not change significantly. Over this 8-year period, the overall viral population in this region evolved toward the less virulent HIV-1A strain, most likely as a consequence of the faster disease progression and lower transmissibility of HIV-1D.
Project Accept is a community randomized, controlled trial to evaluate the efficacy of community mobilization, mobile testing, same-day results, and post-test support for the prevention of HIV infection in Thailand, Tanzania, Zimbabwe, and South Africa. We evaluated the accuracy of in-country HIV rapid testing and determined HIV prevalence in the Project Accept pilot study.
Two HIV rapid tests were performed in parallel in local laboratories. If the first two rapid tests were discordant (one reactive, one non-reactive), a third HIV rapid test or enzyme immunoassay was performed. Samples were designated HIV NEG if the first two tests were non-reactive, HIV DISC if the first two tests were discordant, and HIV POS if the first two tests were reactive. Samples were re-analyzed in the United States using a panel of laboratory tests.
HIV infection status was correctly determined based on-in country testing for 2,236 (99.5%) of 2,247 participants [7 (0.37%) of 1,907 HIV NEG samples were HIV-positive; 2 (0.63%) of 317 HIV POS samples were HIV-negative; 2 (8.3%) of 24 HIV DISC samples were incorrectly identified as HIV-positive based on the in-country tie-breaker test]. HIV prevalence was: Thailand: 0.6%, Tanzania: 5.0%, Zimbabwe 14.7%, Soweto South Africa: 19.4%, Vulindlela, South Africa: 24.4%, (overall prevalence: 14.4%).
In-country testing based on two HIV rapid tests correctly identified the HIV infection status for 99.5% of study participants; most participants with discordant HIV rapid tests were not infected. HIV prevalence varied considerably across the study sites (range: 0.6% to 24.4%).
ClinicalTrials.gov registry number NCT00203749.
Microbial translocation has been implicated as a contributing factor to the heightened immune activation observed during HIV-1 disease progression. When examined in a longitudinal study of HIV-1 seroconverters in Rakai, Uganda microbial translocation was not associated with HIV-1 disease progression. However, the role of general immune activation in HIV disease progression in this population was not fully examined.
Longitudinal serum samples of HIV-1 seroconverters in three HIV-1 disease progression groups [long-term nonprogressors (LTNP), standard progressors (SP), and rapid progressors (RP)] from Rakai, Uganda, were tested for levels of C-reactive protein (CRP), a marker for immune activation.
CRP levels significantly increased in the SP group (p<0.0001), but not in the RP group or the LTNP group. CRP levels during the first year post-HIV-seroconversion in the RP group were significantly higher than those observed in the LTNP group (p<0.05). For the entire population CRP levels negatively correlated with Lipopolysaccharide levels (p<0.05) and were not associated with endotoxin antibody levels.
This study suggests that in this population increased immune activation is significantly associated with HIV-1 disease progression, but not microbial translocation.
Liver disease is a leading cause of mortality among HIV-infected persons in the US and Europe; however, data regarding effects of HIV and anti-retroviral therapy (ART) on liver disease in Africa remains sparse.
500 HIV-infected participants in an HIV care program in Rakai, Uganda were frequency-matched by age, gender and site to 500 HIV-uninfected participants in a population cohort. All participants underwent transient elastography (FibroScan®) to quantify liver stiffness measurements (LSM) and identify participants with significant liver fibrosis, defined as LSM ≥9.3 kPa (≈ Metavir F ≥2). 962 (96 %) of participants had valid LSM data. Risk factors for liver fibrosis were identified by estimating adjusted prevalence risk ratios (adjPRR) and 95% confidence intervals (CI) using modified Poisson multivariate regression.
The prevalence of significant fibrosis was 17% among HIV-infected and 11% in HIV-uninfected participants (p =0.008). In multivariate analysis, HIV infection was associated with a 50% increase in liver fibrosis (adjPRR 1.5, 95%CI 1.1–2.1; p=0.010). Fibrosis was also associated with male gender (adjPRR 1.4, 95% CI 1.0–1.9; p=0.045), herbal medicine use (adjPRR 2.0, 95%CI 1.2–3.3; p=0.005), heavy alcohol consumption (adjPRR 2.3, 95% CI 1.3–3.9; 0.005), occupational fishing (adjPRR 2.5, 1.2–5.3; p=0.019), and chronic HBV infection (adjPRR 1.7, 95% CI 1.0–3.1; p=0.058). Among HIV-infected participants, ART appeared to reduce fibrosis risk (adjPRR 0.6, 95% CI 0.4–1.0; p=0.030).
The burden of liver fibrosis among rural Ugandans is high, particularly among persons with HIV infection. These data suggest that liver disease may represent a significant cause of HIV-related morbidity and mortality in Africa; clarifying the etiology of liver disease in this population is a research priority.
HIV; fibrosis; hepatitis co-infection; liver; Uganda
HIV incidence is the rate of new infections in a population over time. HIV incidence is a critical indicator needed to assess the status and trends of the HIV epidemic in populations and guide and assess the impact of prevention interventions.
Several methods exist for estimating population-level HIV incidence: direct observation of HIV incidence through longitudinal follow-up of persons at risk for new HIV infection, indirect measurement of HIV incidence using data on HIV prevalence and mortality in a population, and direct measurement of HIV incidence through use of tests for recent infection (TRIs) that can differentiate “recent” from “non-recent” infections based on biomarkers in cross-sectional specimens. Given the limitations in measuring directly observed incidence and the assumptions needed for indirect measurements of incidence, there is an increasing demand for TRIs for HIV incidence surveillance and program monitoring and evaluation purposes.
Over ten years since the introduction of the first TRI, a number of low-, middle-, and high-income countries have integrated this method into their HIV surveillance systems to monitor HIV incidence in the population. However, the accuracy of these assays for measuring HIV incidence has been unsatisfactory to date, mainly due to misclassification of chronic infections as recent infection on the assay. To improve the accuracy of TRIs for measuring incidence, countries are recommended to apply case-based adjustments, formula-based adjustments using local correction factors, or laboratory-based adjustment to minimize error related to assay misclassification. Multiple tests may be used in a recent infection testing algorithm (RITA) to obtain more accurate HIV incidence estimates.
There continues to be a high demand for improved TRIs and RITAs to monitor HIV incidence, determine prevention priorities, and assess impact of interventions. Current TRIs have noted limitations, but with appropriate adjustments, interpreted in parallel with other epidemiologic data, may still provide useful information on new infections in a population. New TRIs and RITAs with improved accuracy and performance are needed and development of these tools should be supported.
In Rakai, Uganda, HIV+ men were randomized to immediate (intervention) or delayed circumcision (controls). Penile swabs were assayed for high risk human papillomavirus (HR-HPV) by Roche HPV Linear Array at enrollment and 24 months (intervention n=103, control n=107). Rate ratios (RR) of HR-HPV were estimated by Poisson regression. At 24 months, HR-HPV prevalence was intervention 55.3% and control 71.7% (RR=0.77, 95%CI 0.62–0.97). Multiple HR-HPV infections were intervention 22.4% and controls 42.5% (RR=0.53, 95%CI 0.33–0.83). New HR-HPV genotypes were acquired by 42.0% of intervention and 57.0% of control arm men (RR=0.74, 95%CI 0.54–1.01, p=0.06). Multiple new HR-HPV genotypes were acquired by 9.9% intervention and 24.7% control arm men (RR = 0.40, 95%CI 0.19–0.84, p = 0.01). Circumcision did not affect the acquisition of single HR-HPV infections (RR=1.00, 95%CI 0.65–1.53) or clearance of HR-HPV (RR=1.09, 95%CI 0.94–1.27). Circumcision of HIV+ men reduced the prevalence and incidence of multiple HR-HPV infections.
Uncircumcised HIV-negative men aged 15-49 years were randomized to immediate circumcision (n=441) or delayed circumcision (n=399). HPV was detected by Roche HPV Linear Array at enrollment, 6, 12 and 24 months. Incident HR-HPV was estimated in men who acquired a new HR-HPV genotype. HR-HPV clearance was determined in men with prior genotype-specific HR-HPV infections. Rate ratios (RR) and 95% confidence intervals (95%CI) of HR-HPV acquisition were estimated by Poisson multiple regression
Enrollment characteristics were comparable between groups. HR-HPV incidence was 19.7/100 py in the intervention (70/355.8 py) and 29.4/100 py (125/424.8 py) in the control arm (RR=0.67, 95%CI 0.51-0.89, p = 0.006.) The incidence of multiple HR-HPV infections was 6.7/100 py in the intervention and 14.8/100 py in control arm (RR = 0.45, 95%CI 0.28-0.73), but there was no significant effect on single infections (RR=0.89, 95%CI 0.60-1.30). HR-HPV incidence was lower in the intervention arm for all genotypes and demographic/behavioral subgroups. The clearance of pre-existing HR-HPV infections was 215.8/100py (205/95 py) in intervention and 159.1/100py (255/160.25 py) in control arm men (adjRR=1.39, 95%CI 1.17-1.64).
Male circumcision reduces the incidence of multiple HR-HPV infections and increases clearance of HR-HPV infections in HIV-uninfected men.
The trial was registered with ClinicalTrials.gov numbers NCT00425984
HIV-1 disease progression is associated with persistent immune activation. However, the nature of this association is incompletely understood. Here, we investigated immune activation in the CD4 T cell compartment of chronically HIV-1 infected individuals from Rakai, Uganda. Levels of CD4 T cell activation, assessed as co-expression of PD-1, CD38 and HLA-DR, correlated directly to viral load and inversely to CD4 count. Deeper characterization of these cells indicated an effector memory phenotype with relatively frequent expression of Ki67 despite their PD-1 expression, and levels of these cells were inversely associated with FoxP3+ regulatory T cells. We therefore use the term deregulated effector memory (DEM) cells to describe them. CD4 T cells with a DEM phenotype could be generated by antigen stimulation of recall responses in vitro. Responses against HIV-1 and CMV antigens were enriched among the DEM CD4 T cells in patients, and the diverse Vβ repertoire of DEM CD4 T cells suggested they include diverse antigen-specificities. Furthermore, the levels of DEM CD4 T cells correlated directly to soluble CD14 (sCD14) and IL-6, markers of innate immune activation, in plasma. The size of the activated DEM CD4 T cell subset was predictive of the rate of disease progression, whereas IL-6 was only weakly predictive and sCD14 was not predictive. Taken together, these results are consistent with a model where systemic innate immune activation and chronic antigen stimulation of adaptive T cell responses both play important roles in driving pathological CD4 T cell immune activation in HIV-1 disease.
It remains controversial as to whether HIV-1 subtypes influence disease progression. Singapore offers a unique opportunity to address this issue due to the presence of co-circulating subtypes. We compared subtype CRF01_AE and non-CRF01_AE infected patients, with regards to estimated annual rate of CD4+ T-cell loss and time from estimated data of seroconversion (EDS) to antiretroviral therapy (ART).
We recruited ART-naive patients with known dates of seroconversion between October 2002 and December 2007 at the Singapore Communicable Disease Centre, the national reference treatment centre. Multilevel mixed-effects models were used to analyse the rate of CD4+ T-cell decline. Time from EDS to ART was analyzed with the Kaplan-Meier survival method and compared with Cox proportional hazards models.
54 patients with previously assigned HIV-1 subtypes (24 CRF01_AE, 17 B, 8 B', 1 CRF33_01B, 3 CRF34_01B and 1 G) were observed for 89 patient-years. Subtype CRF01_AE and non-CRF01_AE infected patients did not differ in age, gender, risk factor, rate of symptomatic seroconversion, baseline CD4+ T-cell count, log10 viral load or haemoglobin concentration. The estimated annual rate of CD4+ T-cell loss was 58 cells/mm3/year (95% CI: 7 to 109; P = 0.027) greater in subtype CRF01_AE infected patients compared to non-CRF01_AE patients, after adjusting for age, baseline CD4+ T-cell count and baseline log10 viral load. The median time from EDS to ART was 1.8 years faster comparing CRF01_AE to non-CRF01_AE infected patient with a 2.5 times (95% CI: 1.2-5.0; P = 0.013) higher hazard for ART initiation, after controlling for age, baseline CD4+ T-cell count and baseline log10 viral load.
Infecting subtype significantly impacted the rate of CD4+ T-cell loss and time to treatment in this cohort. Studies to understand the biological basis for this difference could further our understanding of HIV pathogenesis.
High prevalences of reduced glomerular filtration rate (GFR) have been reported from HIV-infected individuals in sub-Saharan Africa when initiating antiretroviral therapy. However little is known about natural history HIV-related kidney disease or about background rates of reduced GFR in HIV-negative individuals in this region.
We estimated GFR from first and last available stored serum samples from 1202 HIV-infected and 664 age-matched and sex-matched HIV-negative individuals in a community-based cohort of HIV-infected and HIV-negative individuals in Rakai, Uganda, between 1994 and 2003. We assessed the prevalence and incidence of mildly (60–89 ml·min−1·1.73 m−2) and moderately (<60 ml·min−1 · 1.73 m−2) reduced GFR using standard analytical methods.
At baseline, 8.4% of HIV-infected and 4.7% of HIV-negative individuals had mildly or moderately reduced GFR (P = 0.002). During follow-up, the rates of decline to a lower GFR category were of 32.4 and 20.3 per 1000 person-years in HIV-infected and HIV-negative subjects, respectively (P = 0.019).
In an unselected community sample of HIV-infected individuals followed in Rakai, Uganda, before the availability of antiretroviral therapy, the prevalence of decreased GFR and the incidence of a decline in GFR category during follow-up were both significantly higher in HIV-infected subjects compared with HIV-negative subjects, although moderately reduced GFR was uncommon.
Africa; chronic kidney disease; cohort study; HIV infection; Uganda
To determine whether heterosexual transmission of HIV differs according to HIV-1 subtype
Retrospective observational cohort
HIV-1 subtype effects on heterosexual HIV-1 transmission were determined among 268 HIV-discordant couples retrospectively identified from a population cohort in Rakai, Uganda. HIV-1 subtype (gag & gp41 sequencing and MHA) and viral loads (RT-PCR) were determined. Adjusted incidence rate ratios (Adj.IRR) of HIV transmission by subtype were estimated by multivariable Poisson regression adjusting for characteristics of index HIV positive and negative partners.
Adjusting for index HIV positive partners age, viral load (VL), stage of disease, genital ulcer (GUD), and HIV negative partners GUD and non use of condoms, subtype A viruses were associated with a higher rate of transmission than subtype D (Adj.IRR, 1.98; 95% CI, 1.17-3.34), but no differences in transmission were observed between recombinant viruses and subtype D (adj. RR, 1.53, p=0.25). Index positive partners' age <30 years (Adj.IRR, 3.44; 95% CI, 1.75 - 6.78) and VL (Adj.IRR, 2.37; 95% CI, 1.75-3.21), and index negative partners GUD (Adj.IRR, 1.71; 95% CI, 1.08 - 2.70) and non
-use of condoms (Adj.IRR, 1.94, 95% CI, 1.15 - 3.28) were significant determinants of HIV transmission.
In Rakai, Uganda, subtype A viruses have a significantly higher rate of heterosexual transmission than subtype D viruses. Differential subtype transmission efficiency may be important for HIV vaccine evaluation and could contribute to subtype-specific HIV epidemics in sub-Saharan Africa.
HIV-1 subtype; discordant couples; HIV transmission; Uganda
To evaluate the utility of a single quantitative PCR (qPCR) measurement of HSV (HSV-1&2) DNA in cervicovaginal lavage (CVL) specimens collected from women with predominantly chronic HSV-2 infection in assessing genital HSV shedding and the clinical course of genital herpes (GH) within a cohort with semiannual schedule of follow up and collection of specimens.
Two previously described methods used for detection of HSV DNA in mucocutaneous swab samples were adapted for quantification of HSV DNA in CVLs. Single CVL specimens from 509 women were tested. Presence and quantity of CVL HSV DNA were explored in relation to observed cross-sectional and longitudinal clinical data.
The PCR assay was sensitive and reproducible with a limit of quantification of ~50 copies per milliliter of CVL. Overall, 7% of the samples were positive for HSV-2 DNA with median log10 HSV-2 DNA copy number of 3.9 (IQR: 2.6-5.7). No HSV-1 was detected. Presence and quantity of HSV-2 DNA in CVL directly correlated with the clinical signs and symptoms of presence of active symptomatic disease with frequent recurrences.
Single qPCR measurement of HSV DNA in CVL fluids of women with chronic HSV-2 infection provided useful information for assessing GH in the setting of infrequent sampling of specimens. Observed positive correlation of the presence and quantity of HSV-2 DNA with the presence of active and more severe course of HSV-2 infection may have clinical significance in the evaluation and management of HSV-2 infected patients.