Background Hepatitis C virus (HCV) infection, clearance and reinfection are best studied in injection drug users (IDU) who have the highest incidence and are representative of most infections. Methods A prospective cohort of HCV negative young IDU was followed from 2000 to 2007, to identify acute and incident HCV and prospectively study infection outcomes. Results Among 1,191 young IDU screened, 731 (61.4%) were HCV negative, and 520 (71.1%) were enrolled into follow-up. Cumulative HCV incidence was 26.7 per 100 person years of observation (PYO) (95% CI, 21.5, 31.6). 95 (70.4%) of 135 acute/incident HCV infections were followed; 21% cleared HCV. Women had a significantly higher incidence of viral clearance compared to men (age-adjusted relative hazard 2.91, 95% CI, 1.68, 5.03) and also showed a significantly faster rate of early HCV viremia decline. Estimated reinfection rate was 24.6 per 100 PYO (95% CI, 11.7, 51.6). Among seven individuals, multiple episodes of HCV reinfection and re-clearance were observed. Conclusions In this large sample of young IDU, females show demonstrative differences in their rates of viral clearance and kinetics of early viral decline. Recurring reinfection and re-clearance suggest possible protection against persistent infection. These results should inform HCV clinical care and vaccine development.

The present study examined reasons for the high incidence of hepatitis C virus (HCV) infection among young injection drug users (IDUs). IDUs <30 years old who tested negative for HCV antibody were enrolled in a prospective cohort. Risk factors for seroconversion were examined using time-dependent regression analyses: 48 of 195 IDUs seroconverted to HCV, for an incidence rate of 25.1/100 person-years (95% confidence interval, 18.7-32.9/100 person-years). Independent risk factors included sharing needles with an HCV-infected sex partner (borderline statistical significance, P=.11) or a person who was not a sex partner, sharing nonsterile drug-preparation equipment, pooling money with another IDU to buy drugs, and exchanging sex for money. Ubiquitous behaviors among young IDUs, such as the forming of injecting or sexual partnerships and consequent sharing of needles and drug preparation equipment, are risk factors for HCV. Interventions to reduce HCV transmission must recognize the importance of relationships on injecting risk.

Background Having opioid dependence and HIV infection are associated with poor HIV-related treatment outcomes. Methods HIV-infected, opioid-dependent subjects (N = 295) recruited from 10 clinical sites initiated buprenorphine/naloxone (BUP/NX) and were assessed at baseline and quarterly for 12 months. Primary outcomes included receiving antiretroviral therapy (ART), HIV-1 RNA suppression, and mean changes in CD4 lymphocyte count. Analyses were stratified for the 119 subjects not on ART at baseline. Generalized estimating equations were deployed to examine time-dependent correlates for each outcome. Results At baseline, subjects on ART (N = 176) were more likely than those not on ART (N = 119) to be older, heterosexual, have lower alcohol addiction severity scores, and lower HIV-1 RNA levels; they were less likely to be homeless and report sexual risk behaviors. Subjects initiating BUP/NX (N = 295) were significantly more likely to initiate or remain on ART and improve CD4 counts over time compared with baseline; however, these improvements were not significantly improved by longer retention on BUP/NX. Retention on BUP/NX for three or more quarters was, however, significantly associated with increased likelihood of initiating ART (β = 1.34 [1.18, 1.53]) and achieve viral suppression (β = 1.25 [1.10, 1.42]) for the 64 of 119 (54%) subjects not on ART at baseline compared with the 55 subjects not retained on BUP/NX. In longitudinal analyses, being on ART was positively associated with increasing time of observation from baseline and higher mental health quality of life scores (β = 1.25 [1.06, 1.46]) and negatively associated with being homo- or bisexual (β = 0.55 [0.35, 0.97]), homeless (β = 0.58 [0.34, 0.98]), and increasing levels of alcohol addiction severity (β = 0.17 [0.03, 0.88]). The strongest correlate of achieving viral suppression was being on ART (β = 10.27 [5.79, 18.23]). Female gender (β = 1.91 [1.07, 3.41]), Hispanic ethnicity (β = 2.82 [1.44, 5.49]), and increased general health quality of life (β = 1.02 [1.00,1.04]) were also independently correlated with viral suppression. Improvements in CD4 lymphocyte count were significantly associated with being on ART and increased over time. Conclusions Initiating BUP/NX in HIV clinical care settings is feasible and correlated with initiation of ART and improved CD4 lymphocyte counts. Longer retention on BPN/NX was not associated with improved prescription of ART, viral suppression, or CD4 lymphocyte counts for the overall sample in which the majority was already prescribed ART at baseline. Among those retained on BUP/NX, HIV treatment outcomes did not worsen and were sustained. Increasing time on BUP/NX, however, was especially important for improving HIV treatment outcomes for those not on ART at baseline, the group at highest risk for clinical deterioration. Retaining subjects on BUP/NX is an important goal for sustaining HIV treatment outcomes for those on ART and improving them for those who are not. Comorbid substance use disorders (especially al...

use is the primary mode of transmission for hepatitis C virus (HCV) infection. Prior studies suggest opioid agonist therapy may reduce the incidence of HCV infection among injection drug users; however, little is known about the effects of this therapy in younger users.OBJECTIVE To evaluate whether opioid agonist therapy was associated with a lower incidence of HCV infection in a cohort of young adult injection drug users.

Young injection drug users (IDUs) in San Francisco may be at high risk for hepatitis C virus (HCV) infection despite access to several needle exchange venues. The authors conducted a cross-sectional study from 1997 to 1999 in San Francisco to estimate the prevalence and incidence of antibody to HCV (anti-HCV) among street-recruited IDUs under age 30, and to examine risk behaviors and sources of sterile needles. Among 308 participants, the prevalence of anti-HCV was 45%. Using statistical modeling, incidence of HCV infection was estimated to be 11 per 100 person years. Independent risk factors for anti-HCV included age (odds ratio [OR], 1.17 per year; 95% confidence interval [CI], 1.05-1.30), years injecting (OR, 1.21 per year; 95% CI, 1.10-1.34), years in San Francisco (OR, 1.06 per year; 95% CI, 1.00-1.14), first injected by a sex partner (OR, 4.06; 95% CI, 1.74-9.52), injected daily (OR, 3.85; 95% CI, 2.07-7.17), ever borrowed a needle (OR, 2.56; 95% CI, 1.18-5.53), bleached last time a needle was borrowed (OR, 0.50; 95% CI, 0.24-1.02), snorted or smoked drugs in the prior year (OR, 0.48; 95% CI, 0.26-0.89), and injected by someone else in the prior month (OR, 0.50; 95% CI, 0.25-0.99). In the prior month, 88% used at least 1 of several needle exchange venues, and 32% borrowed a needle. We conclude that anti-HCV prevalence is lower than in previous studies of older IDUs, but 11% incidence implies high risk of HCV infection in a long injecting career. Despite access to sterile needles, borrowing of needles persisted.