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1.  HIV infection among young parturient women in Brazil: prevalence and associated risk factors 
AIDS and behavior  2014;18(0 1):10.1007/s10461-013-0534-9.
Our goal was to estimate prevalence of HIV among young women in labor. A national, probability-based, cross-sectional study was performed among pregnant women, aged 15–24 years, who were attending Brazilian public hospitals. The study included 2,071 of 2,400 women selected (86.3% participation). Mean age was 20.2 years (SD = 2.7). HIV prevalence was 0.7% (95% CI, 0.4%–1.1%). Living in the North region of the country and having previous sexually transmitted infections were associated with HIV infection. Our survey of young pregnant women found higher prevalence than expected for women of all ages in Brazil (0.42%), indicating that the epidemic persists among heterosexuals.
PMCID: PMC3818388  PMID: 23754614
HIV; pregnancy; Brazil; risk factors; youth
2.  Syphilis and HIV co-infection in patients who attend an AIDS outpatient clinic in Vitoria, Brazil 
AIDS and behavior  2014;18(0 1):10.1007/s10461-013-0533-x.
Our goal was to determine the prevalence of, and risk factors associated with, syphilis in HIV-infected patients who attend an AIDS outpatient clinic in Vitoria, Brazil. We conducted a cross-sectional study—including interviews for demographic, behavioral, and clinical characteristics—and blood collection (venipuncture and fingerstick) for VDRL and treponemal tests (rapid test) in a total of 438 patients. The mean age was 43.0 years (SD = 11), and mean years of school was 8.1 (SD = 4.2). The prevalence of syphilis was 5.3% (95% CI, 3.3%–7.3%). The treponemal test was positive in 18.9% of participants. In multivariate analysis, prevalent syphilis infection was independently associated with male gender (AOR 4.6, 95% CI, 1.1–20.0), a history of male-male sex (AOR 1.8, 95% CI, 1.6–4.1), current use of antiretroviral therapy (AOR 5.5, 95% CI, 1.7–16.7), and history of treated syphilis infection (AOR 5.5, 95% CI, 2.0–15.8). Syphilis prevalence was high in patients living with HIV/AIDS who attend an AIDS clinic; therefore, routine STI counseling and screening should be included in their care.
PMCID: PMC3818508  PMID: 23732958
syphilis; HIV; co-infection; prevalence; screening
3.  The effects of female sex, viral genotype and IL28B genotype on spontaneous clearance of acute hepatitis C virus infection 
Hepatology (Baltimore, Md.)  2013;59(1):109-120.
Although 20–40% of persons with acute HCV infection demonstrate spontaneous clearance, the time-course and factors associated with clearance remain poorly understood. We investigated the time to spontaneous clearance and predictors among participants with acute HCV using Cox proportional hazards analyses. Data for this analysis were drawn from an international collaboration of nine prospective cohorts evaluating outcomes following acute HCV infection. Among 632 participants with acute HCV, 35% were female, 82% were Caucasian, 49% had IL28B CC genotype (rs12979860), 96% had injected drugs ever, 47% were infected with HCV genotype 1 and 5% had HIV co-infection. Twenty-eight percent were HCV antibody negative/RNA positive at the time of acute HCV detection (early acute HCV). During follow-up, spontaneous clearance occurred in 173 of 632 and at one year following infection, 25% (95%CI: 21%, 29%) had cleared virus. Among those with clearance, the median time to clearance was 16.5 weeks (IQR: 10.5, 33.4 weeks), with 34%, 67% and 83% demonstrating clearance at three, six and twelve months. Adjusting for age, factors independently associated with time to spontaneous clearance included female sex [adjusted hazards ratio (AHR) 2.16; 95%CI 1.48, 3.18], IL28B CC genotype (vs. CT/TT, AHR 2.26; 95%CI 1.52, 3.34), and HCV genotype 1 (vs. non-genotype 1, AHR 1.56; 95%CI 1.06, 2.30). The effect of IL28B genotype and HCV genotype on spontaneous clearance was greater among females compared to males.
Female sex, favorable IL28B genotype and HCV genotype 1 are independent predictors of spontaneous clearance. Further research is required to elucidate the observed sex-based differences in HCV control.
PMCID: PMC3972017  PMID: 23908124
injection drug use; hepatitis C virus; HIV; incident infection; longitudinal studies
4.  Hepatitis C Virus Serosorting in People Who Inject Drugs: Sorting Out the Details 
The Journal of Infectious Diseases  2013;208(12):1929-1931.
PMCID: PMC3836470  PMID: 24136791
injection drugs; testing; nucleic acid test
5.  Cohort Profile: The International Collaboration of Incident HIV and Hepatitis C in Injecting Cohorts (InC3) Study 
The International Collaboration of Incident HIV and Hepatitis C in Injecting Cohorts (InC3) Study is an international multi-cohort project of pooled biological and behavioural data from nine prospective cohorts of people who inject drugs (PWID). InC3 brings together researchers from Australia, Canada, USA and the Netherlands with expertise in epidemiology, biostatistics, clinical and behavioural sciences, virology and immunology to investigate research questions relevant to hepatitis C virus (HCV) and HIV outcomes. InC3 was established to: (i) create a merged multi-cohort study of pooled data from well-characterized cohorts of PWID with prospective data on HIV and HCV infections, with a particular focus on HCV; (ii) facilitate new studies not possible within individual cohorts; and (iii) bring together researchers across disciplines to answer a broad range of research questions. Study cohorts identify acute HCV cases through follow-up of high-risk HCV antibody–negative PWID or through clinical referral networks. To date, data from 1986 to 2010 have been received from all contributing cohorts, with 821 HCV-infected and 1216 HCV-uninfected participants (overall, n = 2037). Data collected include demographics, host genetics, HCV ribonucleic acid testing, alanine aminotransferase testing, HIV/hepatitis B virus testing, HCV therapy, loss to follow-up and mortality. Potential collaborators should contact the InC3 PI Dr Kimberley Page ( for further information.
PMCID: PMC3887561  PMID: 23203695
6.  Undisclosed Human Immunodeficiency Virus Risk Factors Identified through a Computer-based Questionnaire Program among Blood Donors in Brazil 
Transfusion  2013;53(11):2734-2743.
HIV risk factor screening among blood donors remains a cornerstone for the safety of blood supply and is dependent on prospective donor self-disclosure and an attentive predonation interview. Residual risk of HIV transmission through blood transfusion is higher in Brazil than in many other countries. Audio computer-assisted structured-interview (ACASI) has been shown to increase self-reporting of risk behaviors.
Study design and methods
This cross-sectional study was conducted between January 2009 and March 2011 at four Brazilian blood centers to identify the population of HIV-negative eligible blood donors that answered face-to-face interviews without disclosing risks, but subsequently disclosed deferrable risk factors by ACASI. Compared to the donor interview, the ACASI contained expanded content on demographics, sexual behavior and other HIV risk factors questions.
901 HIV-negative blood donors were interviewed. On the ACASI, 13% of donors (N=120) declared a risk factor that would have resulted in deferral that was not disclosed during the face-to-face assessment. The main risk factors identified were recent unprotected sex with an unknown or irregular partner (49 donors), sex with a person with exposure to blood/ fluids (26 donors), multiple sexual partners (19 donors), and male-male sexual behavior (10 donors). Independent factors associated with the disclosure of any risk factor for HIV were age (≥40 years vs. 18–25 years, AOR=0.45; 95% CI 0.23–0.88) and blood center (Hemope vs. Hemominas, AOR=2.51; 95% CI 1.42–4.44).
ACASI elicited increased disclosure of HIV risk factors among blood donors. ACASI may be a valuable modality of interview to be introduced in Brazilian blood banks.
PMCID: PMC3708980  PMID: 23521083
HIV; transfusion; blood donors; ACASI; Brazil; risk factors
7.  Intimate Injection Partnerships Are at Elevated Risk of High-Risk Injecting: A Multi-Level Longitudinal Study of HCV-Serodiscordant Injection Partnerships in San Francisco, CA 
PLoS ONE  2014;9(10):e109282.
It is increasingly recognized that the risk for HIV and hepatitis C (HCV) transmission among people who inject drugs (PWID), such as syringe sharing, occurs in the context of relationships between (at least) two people. Evidence suggests that the risk associated with injection behavior varies with injection partner types.
We utilized longitudinal dyad-level data from a study of young PWID from San Francisco (2006 to 2013) to investigate the relationship-level factors influencing high-risk injecting within HCV-serodiscordant injection partners (i.e., individuals who injected together ≥5 times in the prior month). Utilizing data from 70 HCV-serodiscordant injection partnerships, we used generalized linear models to examine relationship-level predictors (i.e., partnership composition, partnership closeness, and partnership dynamics) of: (1) receptive syringe sharing (RSS); and (2) receptive cooker use (RCU), as reported by the HCV-negative injection partner.
As reported by the “at-risk” HCV-negative injection partner, receptive syringe sharing (RSS) and receptive cooker use (RCU) were 19% and 33% at enrollment, and 11% and 12% over all visits (total follow-up time 55 person-years) resulting in 13 new HCV-infections (incidence rate: 23.8/100 person-years). Person-level factors, injection partnership composition, and partnership dynamics were not significantly associated with either RSS or RCU. Instead, intimate injection partnerships (those who lived together and were also in a sexual relationship) were independently associated with a 5-times greater risk of both RSS and a 7-times greater risk of RCU when compared to injecting only partnerships.
Our findings suggest a positive, and amplified effect of relationship factors on injecting drug risk behaviors among young PWID injection partnerships. The majority of interventions to reduce injection drug use related harms focus on individual-based education to increase drug use knowledge. Our findings support the need to expand harm reduction strategies to relationship-based messaging and interventions.
PMCID: PMC4186818  PMID: 25286346
9.  KIR Genotypic Diversity Can Track Ancestries in Heterogeneous Populations: A Potential Confounder for Disease Association Studies 
Immunogenetics  2011;64(2):97-109.
Killer cell immunoglobulin-like receptors (KIR) are encoded by highly polymorphic genes that regulate the activation of natural killer (NK) cells and other lymphocyte subsets, and likely play key roles in innate and adaptive immunity. Association studies increasingly implicate KIR in disease predisposition and outcome but could be confounded by unknown KIR genetic structure in heterogeneous populations. To examine this we characterized the diversity of 16 KIR genes in 712 Northern Californians (NC) stratified by selfassigned ethnicities, and compared the profiles of KIR polymorphism with other US and global populations using a reference database. Sixty-eight distinct KIR genotypes were characterized: 58 in 457 Caucasians (NCC); 17 in 47 African Americans (NCAA); 21 in 80 Asians (NCA); 20 in 74 Hispanics (NCH) and 18 in 54 “other” ethnicities (NCO). KIR genotype patterns and frequencies in the 4 defined ethnicities were compared with each other and with 34 global populations by phylogenetic analysis. Although there were no population-specific genotypes, the KIR genotype frequency patterns faithfully traced the ancestry of NCC, NCAA and NCA but not of NCH whose ancestries are known to be more heterogeneous. KIR genotype frequencies can therefore track ethnic ancestries in modern urban populations. Our data emphasize the importance of selecting ethnically matched controls in KIR based studies to avert spurious associations.
PMCID: PMC4143378  PMID: 21898189
KIR genotype frequency; Polymorphism; Northern California population; Ethnicity
10.  Injection Drug Use and Hepatitis C Virus Infection in Young Adult Injectors: Using Evidence to Inform Comprehensive Prevention 
The hepatitis C virus (HCV) virus epidemic is ongoing in the United States and globally. Incidence rates remain high, especially in young adult injection drug users. New outbreaks of HCV in the United States among young adults, in predominantly suburban and rural areas, have emerged and may be fueling an increase in HCV. This paper discusses some key HCV prevention strategies that to date have not been widely researched or implemented, and wherein future HCV prevention efforts may be focused: (1) reducing sharing of drug preparation equipment; (2) HCV screening, and testing and counseling; (3) risk reduction within injecting relationships; (4) injection cessation and “breaks”; (5) scaled-up needle/syringe distribution, HCV treatment, and vaccines, according to suggestions from mathematical models; and (6) “combination prevention.” With ongoing and expanding transmission of HCV, there is little doubt that there is a need for implementing what is in the prevention “toolbox” as well as adding to it. Strong advocacy and resources are needed to overcome challenges to providing the multiple and comprehensive programs that could reduce HCV transmission and associated burden of disease worldwide in people who inject drugs.
PMCID: PMC3722077  PMID: 23884063
hepatitis C virus; prevention; injection drug users; syringe access; counseling and testing; harm reduction; HCV treatment; HCV vaccine; combination prevention
11.  Increased hepatitis C virus vaccine clinical trial literacy following a brief intervention among people who inject drugs 
Drug and alcohol review  2012;32(4):419-425.
Background and Aims
While people who inject drugs are at high risk of hepatitis C virus (HCV) infection and will be the target population for future HCV vaccine trials, little is known about clinical trial literacy (CTL) in this group. We assessed the impact of a brief intervention (BI) designed to improve HCV vaccine CTL among people who inject drugs in Sydney, Australia.
Design and Methods
People who inject drugs enrolled in a community-based prospective observational study between November 2008 and September 2010 (n = 102) completed a CTL assessment followed immediately by the BI. Post-test assessment was conducted at 24 weeks.
The median age of the sample was 27 years, 73% were male and 60% had 10 or less years of schooling. The median time since first injection was five years and 20% reported daily or more frequent injecting. The mean number of correct responses increased from 5.3 to 6.3/10 (t = −.4.2; 101df, P < 0.001) 24 weeks post-intervention. Statistically significant differences were observed for three knowledge items with higher proportions of participants correctly answering questions related to randomisation (P = 0.002), blinding (P = 0.005) and vaccine-induced seropositivity (P = 0.003) post-intervention.
Discussion and Conclusions
A significant increase in HCV vaccine CTL was observed, suggesting that new and relatively novel concepts can be learned and recalled in this group. These findings support the feasibility of future trials among this population.
PMCID: PMC3567229  PMID: 23113829
hepatitis C virus; injecting drug use; clinical trial literacy; brief intervention; vaccine preparedness study
12.  Preference, acceptability and implications of the rapid hepatitis C screening test among high-risk young people who inject drugs 
BMC Public Health  2014;14:645.
People who inject drugs (PWID) are at highest risk for hepatitis C virus (HCV) infection, yet many remain unaware of their infection status. New anti-HCV rapid testing has high potential to impact this.
Young adult (<30 years) active PWID were offered either the rapid OraQuick® or standard anti-HCV test involving phlebotomy, then asked to complete a short questionnaire about testing perceptions and preferences. Sample characteristics, service utilization, and injection risk exposures are assessed with the HCV testing choice as the outcome, testing preferences, and reasons for preference.
Of 129 participants: 82.9% (n = 107) chose the rapid test. There were no significant differences between those who chose rapid vs. standard testing. A majority (60.2%) chose the rapid test for quick results; most (60.9%) felt the rapid test was accurate, and less painful (53.3%) than the tests involving venipuncture.
OraQuick® anti-HCV rapid test was widely accepted among young PWID. Our results substantiate the valuable potential of anti-HCV rapid testing for HCV screening in this high risk population.
PMCID: PMC4091768  PMID: 24965699
Hepatitis C virus; Rapid testing; Injection drug users
13.  Injecting Risk Behavior among Traveling Young Injection Drug Users: Travel Partner and City Characteristics 
Young injection drug users (IDUs), a highly mobile population, engage in high levels of injecting risk behavior, yet little is understood about how such risk behavior may vary by the characteristics of the cities to which they travel, including the existence of a syringe exchange program (SEP), as well as travel partner characteristics. In 2004–2005, we conducted a 6-month prospective study to investigate the risk behavior of 89 young IDUs as they traveled, with detailed information gathered about 350 city visits. In multivariable analyses, travel to larger urban cities with a population of 500,000–1,000,000 was significantly associated with injecting drugs (adjusted odds ratio (AOR) = 3.71; 95 % confidence interval (CI), 1.56–8.82), ancillary equipment sharing (AES; AOR = 7.05; 95 % CI, 2.25–22.06) and receptive needle sharing (RNS; AOR = 5.73; 95 % CI, 1.11–27.95), as compared with visits to smaller cities with populations below 50,000. Region of the country, and the existence of a SEP within the city visited, were not independently associated with injecting drugs, AES, or RNS during city visits. Traveling with more than one injecting partner was associated with injecting drugs during city visits (AOR = 2.77; 95 % CI, 1.46–5.27), when compared with traveling alone. Additionally, both non-daily and daily/almost daily alcohol use during city visits were associated with AES (AOR = 3.37; 95 % CI, 1.42–7.68; AOR = 3.03; 95 % CI, 1.32–6.97, respectively) as compared with no alcohol consumption. Traveling young IDUs are more likely to inject when traveling with other IDUs and to engage in higher risk injection behavior when they are in large cities. Risk behavior occurring in city visits, including equipment sharing and alcohol consumption, suggests further need for focused interventions to reduce risk for viral infection among this population.
PMCID: PMC3665972  PMID: 22744293
Young IDUs; Travelers; Injecting risk; Ancillary equipment sharing; Receptive needle sharing; City characteristics; Travel partners
14.  Biomarker validation of recent unprotected sexual intercourse in a prospective study of young women engaged in sex work in Phnom Penh, Cambodia 
Sexually transmitted diseases  2013;40(6):462-468.
A study of female sex workers in Phnom Penh, Cambodia found self-reported condom use to be of questionable validity, particularly among amphetamine-type stimulant (ATS) users and those with multiple partners.
Accurate measurement of unprotected sex is essential in HIV prevention research. Since 2001, the 100% Condom Use Program targeting female sex workers (FSW) has been a central element of the Cambodian National HIV/AIDS Strategy. We sought to assess the validity of self-reported condom use using the rapid prostate-specific antigen (PSA) test among Cambodian FSW.
From 2009 to 2010 we enrolled 183 FSW in Phnom Penh in a prospective study of HIV risk behavior. PSA test results from the OneStep ABAcard® were compared to self-reported condom use in the past 48 hours at quarterly follow-up visits.
Among women positive for seminal fluid at the first follow-up visit, 42% reported only protected sex or no sex in the detection period. Discordant results were more likely among brothel and street-based FSW vs. entertainment (56% vs. 17%), recent (last 3 months) ATS users (53% vs. 20%), and those with >5 partners in the past month (58% vs. 13%). In multivariable regression models, positive PSA results were associated with recent ATS use (Adjusted Risk Ratio (ARR) = 1.5; 95% confidence interval (CI):1.1 – 2.2), having a non-paying last sex partner (ARR=1.7; CI:1.2 – 2.5), and sex work venue (ARR=3.0; CI:1.4 – 6.5). Correspondingly, women with a non-paying last sex partner were more likely to report unprotected sex (ARR=1.5; CI:1.1 – 2.2), but no associations were found with sex work venue or ATS use.
Results confirm the questionable validity of self-reported condom use among FSW. The PSA biomarker assay is an important monitoring tool in HIV/STI research including prevention trials.
PMCID: PMC3891890  PMID: 23680902
15.  Higher risk of incident hepatitis C virus among young women who inject drugs compared with young men in association with sexual relationships: a prospective analysis from the UFO Study cohort 
BMJ Open  2014;4(5):e004988.
Female injection drug users (IDUs) may report differences in injection behaviours that put them at greater risk for hepatitis C virus (HCV). Few studies have examined these in association with HCV incidence.
Longitudinal data from a cohort of 417 HCV-uninfected IDU aged 30 or younger were analysed. Cox proportional hazards was used to model female sex as a predictor of new HCV infection. General estimating equation (GEE) analysis was used to model female sex as a predictor of HCV-associated risk behaviour prospectively.
Women were significantly more likely than men to become infected with HCV during study follow-up (HR 1.4, p<0.05), and were also more likely than men to report high-risk injecting behaviours, especially in the context of sexual and injecting relationships. Sex differences in injecting behaviours appeared to explain the relationship between sex and HCV infection.
Young women’s riskier injection practices lead to their higher rates of HCV infection. Further study on the impact of intimate partnership on women’s risk behaviour is warranted.
PMCID: PMC4039809  PMID: 24875490
Public Health
16.  Frequent Longitudinal Sampling of Hepatitis C Virus Infection in Injection Drug Users Reveals Intermittently Detectable Viremia and Reinfection 
Defining clear hepatitis C virus (HCV) infection outcomes, including reinfection and viral intercalation after clearance of infection, requires ongoing, frequent follow-up, most importantly with longitudinal viral sequencing. Patients who have cleared HCV infection may demonstrate sustained viral clearance despite ongoing HCV exposure.
Background. Detection of hepatitis C virus (HCV) reinfection and intercalation (ie, intermittent recurrent bouts of viremia with homologous virus interspersed with aviremic periods) requires extensive and frequent evaluation and viral sequencing.
Methods. HCV infection outcomes were studied prospectively in active injection drug users with recurrent HCV RNA–positive tests after serial negative results. HCV viremia and viral sequences (Core/E1) were assessed from monthly blood samples.
Results. Viral clearance, reinfection, and intercalating infection were all detected. Among 44 participants with apparently resolved HCV (26 incident HCV clearers and 18 enrolled with already resolved infection), 36 (82%) remained persistently HCV RNA negative, but 8 demonstrated intermittent recurrent viremia. Four of these (50%) had confirmed reinfection with a heterologous virus; 3 demonstrated viral intercalation, and 1 was not classifiable as either. Estimated incidence of first reinfection was 5.4 per 100 person-years (95% confidence interval, 2.0–14.5). Six (75%) participants, including 3 of 4 with reinfection, demonstrated sustained viral clearance for a median of 26 months since last HCV RNA test.
Conclusions. These results show that frequent monitoring and viral sequencing are required to correctly assess HCV outcomes and estimate incidence of reinfection (which was previously overestimated). Sustained clearance may take many months and occur after episodes of reinfection and viral intercalation. Three of 4 subjects who had confirmed reinfection showed evidence of long-term clearance. Viral intercalation occurs with significant frequency. Further studies of these events, especially immunological, are needed to inform HCV clinical care and vaccine development.
PMCID: PMC3540042  PMID: 23090930
hepatitis C virus; viral sequencing; reinfection; intercalation; young IDU
17.  Hazardous alcohol consumption among young adult IDU and its association with high risk behaviors* 
Drug and alcohol dependence  2012;127(0):143-149.
Heavy alcohol consumption has been associated with risk-taking behaviors in intravenous drug users (IDU). However, limited information exists on the relationship between alcohol use and injecting and sexual risk in young adult IDU (<30 years) who are at risk for hepatitis C virus (HCV) and HIV infection.
We conducted a cross-sectional study of young adult IDU in San Francisco (2006-2012) who had not previously tested positive for HCV. Participants completed a structured interview and HCV testing. We examined whether hazardous drinking (Alcohol Use Disorders Test – Consumption [AUDIT-C] 3-9 for women and 4-9 for men) and probable dependent drinking (AUDIT-C 10-12) levels were associated with injecting and sexual risk behaviors and HCV status, indicated by adjusted odds ratios (AOR) in separate models adjusted for potential confounders.
Of the 326 participants, 139 (42.6%) were hazardous drinkers and 82 (25.2%) were probable dependent drinkers; thus over two-thirds evidenced problem drinking. Being a hazardous drinker was significantly associated with injecting drug residue from another's drug preparation equipment (AOR 1.93). Probable dependent drinking was significantly associated sharing non-sterile drug preparation equipment (AOR 2.59), and inversely, with daily/near daily injecting (AOR 0.42). Both heavy drinking levels were associated with having ≥2 sexual partners (AOR 2.43 and 2.14). Drinking category was not associated with HCV test results.
The young adult IDU reported consuming alcohol at very high levels, which was associated with some unsafe sexual and injecting behaviors. Our study demonstrates the urgent need to intervene to reduce alcohol consumption in this population.
PMCID: PMC3762448  PMID: 22819868
Young Intravenous Drug Users; Alcohol; Alcohol Dependence; Injecting Risk Behaviors
18.  People who Inject Drugs, HIV Risk, and HIV Testing Uptake in Sub-Saharan Africa 
Dramatic rises in injection drug use (IDU) in sub-Saharan Africa account for increasingly more infections in a region already overwhelmed by the HIV epidemic. There is no known estimate of the number of people who inject drugs (PWID) in the region, or the associated HIV prevalence in PWID. We reviewed literature with the goal of describing high-risk practices and exposures in PWID in sub-Saharan Africa, as well as current HIV prevention activities aimed at drug use. The literature search looked for articles related to HIV risk, injection drug users, stigma, and HIV testing in sub-Saharan Africa. This review found evidence demonstrating high rates of HIV in IDU populations in sub-Saharan Africa, high-risk behaviors of the populations, lack of knowledge regarding HIV, and low HIV testing uptake. There is an urgent need for action to address IDU in order to maintain recent decreases in the spread of HIV in sub-Saharan Africa.
PMCID: PMC3800507  PMID: 23164598
HIV risk; HIV testing; injection drug use; stigma; sub-Saharan Africa
19.  Research Participation as Work: Comparing the Perspectives of Researchers and Economically Marginalized Populations 
American journal of public health  2012;102(7):1254-1259.
We examined the historical and regulatory framework of research with human participants in the United States, and described some possible unintended consequences of this framework in the context of paying young injection drug users for their time participating in behavioral and medical research. We drew upon our own experiences while conducting a long-running epidemiological study of hepatitis C virus infection.
We found that existing ethical and regulatory framings of research participation may lead to injustices from the perspectives of research participants.
We propose considering research participation as a specialized form of work and the use of community advisory boards to facilitate discussion about appropriate compensation for research participation among economically marginalized populations.
PMCID: PMC3478002  PMID: 22594754
20.  Sex work and HIV in Cambodia: trajectories of risk and disease in two cohorts of high-risk young women in Phnom Penh, Cambodia 
BMJ Open  2013;3(9):e003095.
HIV prevalence among Cambodian female sex workers (FSW) is among the highest in Southeast Asia. We describe HIV prevalence and associated risk exposures in FSW sampled serially in Phnom Penh, Cambodia (Young Women's Health Study (YWHS)), before and after the implementation of a new law designed to combat human trafficking and sexual exploitation.
Cross-sectional analysis of baseline data from two prospective cohorts.
Community-based study in Phnom Penh, Cambodia.
Women aged 15–29 years, reporting ≥2 sexual partners in the last month and/or engaged in transactional sex in the last 3 months, were enrolled in the studies in 2007 (N=161; YWHS-1), and 2009 (N=220; YWHS-2) following information sessions where 285 and 345 women attended.
Primary outcomes
HIV prevalence, sexual risk behaviour, amphetamine-type stimulant (ATS) and alcohol use, and work-related factors were compared in the two groups, enrolled before and after implementation of the new law.
Participants in the two cohorts were similar in age (median 25 years), but YWHS-2 women reported fewer sex partners, more alcohol use and less ATS use. A higher proportion of YWHS-2 compared with YWHS-1 women worked in entertainment-based venues (68% vs 31%, respectively). HIV prevalence was significantly lower in the more recently sampled women: 9.2% (95% CI 4.5% to 13.8%) vs 23% (95% CI 16.5% to 29.7%).
Sex work context and risk have shifted among young FSW in Phnom Penh, following implementation of anti-prostitution and anti-trafficking laws. While both cohorts were recruited using the same eligibility criteria, more recently sampled women had lower prevalence of sexual risk and HIV infection. Women engaging more directly in transactional sex have become harder to sample and access. Future prevention research and programmes need to consider how new policies and demographic changes in FSW impact HIV transmission.
PMCID: PMC3773643  PMID: 24022389
21.  The Impact of Human T-Cell Lymphotropic Virus I Infection on Clinical and Immunologic Outcomes in Patients Coinfected With HIV and Hepatitis C Virus 
HIV, hepatitis C (HCV), and human T-cell lymphotropic virus I (HTLV-1) are associated with high global burdens of disease, notably in resource-poor locales. They share similar routes of transmission and cause chronic infections with associated morbidity. We performed a cross-sectional study to assess the impact of HTLV-1 infection on clinical outcomes in HIV/HCV-coinfected patients.
We enrolled 102 (72.3%) with HIV/HCV coinfection (Group 1) and 39 (27.7%) triply infected with HIV, HCV, and HTLV-1 (Group 2). We reviewed medical records of two groups of patients followed in two outpatients services in Salvador, Brazil. We collected and compared demographic, behavioral-related information, immunologic, virologic, and histologic parameters for HIV-1 and HCV infection.
Demographics, virologic, and immunologic characteristics were similar in the two groups; a higher proportion of triply infected patients (Group 2) reported any history of injection drug use compared with dually infected (Group 1) patients (75% vs 45.8%; P = 0.003). No differences were seen between groups in HIV clinical outcomes (CD4 count and viral load). Alanine aminotransferase levels were significantly higher in HIV/HCV-coinfected patients (P = 0.045). Liver fibrosis damage based on Metavir scores was similar between groups (0.97) but was worse with lower CD4 cell count (under 200 cells/mm3) (P = 0.01).
HIV/HTLV-1 and HIV/HCV coinfections may worsen clinical related outcomes, but virologic and immunologic outcomes were similar in both groups. Hepatic measures were worse in patients with more severe immunosuppression.
PMCID: PMC3747031  PMID: 21857319
HIV-1 and HCV coinfection; HIV-1; HCV; and HTLV-1 triple infection
22.  HIV vaccine trial willingness among injection and non-injection drug users in two urban centres, Barcelona and San Francisco 
Vaccine  2011;29(10):1991-1996.
Being able to recruit high-risk volunteers who are also willing to consider future participation in vaccine trials are critical features of vaccine preparedness studies. We described data from two cohorts of injection- and non-injection drug users in Barcelona, Spain [Red Cross centre] and in San Francisco, USA, [UFO-VAX study] at high risk of HIV/HCV infection to assess behaviour risk exposure and willingness to participate in future preventive HIV vaccine trials. We successfully identified drug-using populations that would be eligible for future HIV vaccine efficacy trials, based on reported levels of risk during screening and high levels of willingness to participate. In both groups, Red Cross and UFO-VAX respectively, HCV infection was highly prevalent at baseline (41% and 34%), HIV baseline seroprevalence was 4.2% and 1.5%, and high levels of willingness were seen (83% and 78%).
PMCID: PMC3747033  PMID: 21241735
HIV; HIV vaccines; IDUs; Injection and non-injection drug users; Willingness to participate in future trials
23.  Candidate hepatitis C vaccine trials and people who inject drugs: Challenges and opportunities 
Vaccine  2010;28(45):7273-7278.
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People who inject drugs (PWID) are at high risk of HCV. Limited evidence of the effectiveness of prevention interventions and low uptake of treatment in this group highlight the need for increased investment in biomedical interventions, notably safe and efficacious vaccines. While several candidates are currently in development, field trials in PWID present challenges, including ethical issues associated with trial literacy, informed consent and standards of care. Significant biological and social factors and differences between HIV and HCV suggest that HCV warrants targeted vaccine preparedness research to lay the groundwork for successful implementation of future trials.
PMCID: PMC3729933  PMID: 20831914
Hepatitis C virus; Vaccine; People who inject drugs
24.  Dental Disease Prevalence among Methamphetamine and Poly-drug Users in an Urban Setting: A Pilot Study 
Rampant tooth decay has been reported among methamphetamine users. We investigated the prevalence of dental disease and associated risk behaviors in methamphetamine users compared to heroin users.
This pilot project is a cross-sectional study of an on-going cohort of young adult injection-drug users (IDUs) in San Francisco. An oral health questionnaire was administered by a research-assistant, and two dentists performed clinical examinations to record the Decayed-Missing-Filled-Surfaces (DMFS) index, presence of residual roots, the Simplified Oral Hygiene Index, and salivary hypofunction.
The prevalence of dental disease among 58 young adult IDUs was strikingly high compared to the U.S. general population, however, there was no difference in the level of dental disease between the methamphetamine and heroin users in this study. The mean DMFS and number of decayed surfaces exceeded 28 in both groups.
While no difference in dental disease between methamphetamine and heroin users was detected, we found a high prevalence of caries and caries-associated behaviors in this sample of young adult IDUs.
Clinical Implications
Given the high level of dental disease observed in this population of young adult IDUs, one next step may be to explore the feasibility and effectiveness of providing low-intensity preventative measures (e.g., distribution of chlorhexidine rinses, xylitol gum, application of fluoride varnishes) through outreach workers.
PMCID: PMC3729940  PMID: 22942146
Caries; drug abuse; oral health
25.  Young Women Engaged in Sex Work in Phnom Penh, Cambodia, Have High Incidence of HIV and Sexually Transmitted Infections, and Amphetamine-Type Stimulant Use: New Challenges to HIV Prevention and Risk 
Sexually transmitted diseases  2011;38(1):33-39.
To estimate prevalence and incidence of HIV and sexually transmitted infections (STI) and associated risk factors among young women working as sex workers (SWs) in Phnom Penh, Cambodia.
A prospective study of young (<29 years) women working as SWs in brothels, entertainment establishments, and freelance. Sociodemographics, sexual risk, and use of amphetamine-type stimulants (ATS) (“yama” and “crystal”) were assessed by self-report. HIV and STI (Chlamydia trachomatis and Neisseria gonorrhoeae) testing were conducted on blood and urine specimens, respectively.
Baseline prevalences of HIV, C. trachomatis, and N. gonorrhoeae were 23%, 11.5%, and 7.8%, respectively. HIV incidence was 3.6 per 100 person-years (95% confidence interval [CI], 1.2%– 11.1%); STI incidence was 21.2 per 100 person-years (95% CI, 12.6%– 35.8%). At baseline, 26.5% reported recent ATS use. HIV infection was associated with freelance SW (adjusted odds ratio, 5.85; 95% CI, 1.59–21.58) and younger age of first sex (≤15 years; adjusted odds ratio, 3.06; 95% CI, 1.01–8.46). Incident STI was associated with duration (per year) of SW (adjusted hazard ratio, 1.1; 95% CI, 1.1–1.2) and recent yama use (adjusted hazard ratio, 3.9; 95% CI, 1.5–10.3).
HIV and STI infection rates were high among SWs working in various settings; freelancers had highest risk. ATS use was associated with incident STI. Venue of sex work and drug prevention should be considered in prevention programs.
PMCID: PMC3729941  PMID: 21085056

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