Integrated respondent-driven sampling and peer support for persons who inject drugs in Haiphong, Vietnam: a case study with implications for interventions.

Combined prevention for HIV among persons who inject drugs (PWID) has led to greatly reduced HIV transmission among PWID in many high-income settings, but these successes have not yet been replicated in resource-limited settings. Haiphong, Vietnam experienced a large HIV epidemic among PWID, with 68% prevalence in 2006. Haiphong has implemented needle/syringe programs, methadone maintenance treatment (MMT), and anti-retroviral treatment (ART), but there is an urgent need to identify high-risk PWID and link them to services. We examined integration of respondent-driven sampling (RDS) and strong peer support groups as a mechanism for identifying high-risk PWID and linking them to services. The peer support staff performed the key tasks that required building and maintaining trust with the participants, including recruiting the RDS seeds, greeting and registering participants at the research site, taking electronic copies of participant fingerprints (to prevent multiple participation in the study), and conducting urinalyses. A 6-month cohort study with 250 participants followed the RDS cross-sectional study. The peer support staff maintained contact with these participants, tracking them if they missed appointments, and providing assistance in accessing methadone and ART. The RDS recruitment was quite rapid, with 603 participants recruited in three weeks. HIV prevalence was 25%, Hepatitis C (HCV) prevalence 67%, and participants reported an average of 2.7 heroin injections per day. Retention in the cohort study was high, with 86% of participants re-interviewed at 6-month follow-up. Assistance in accessing services led to half of the participants in need of methadone enrolled in methadone clinics, and half of HIV-positive participants in need of ART enrolled in HIV clinics by the 6-month follow-up. This study suggests that integrating large-scale RDS and strong peer support may provide a method for rapidly linking high-risk PWID to combined prevention and care, and greatly reducing HIV transmission among PWID in resource-limited settings.

A community-based intervention to decrease the prevalence of HIV viremia among people who inject drugs in Vietnam.

Background: In most low-to-middle-income countries, HIV control at the population level among people who inject drugs (PWID) remains a major challenge. We aimed to demonstrate that an innovative intervention can identify HIV-positive PWID in the community who are not treated efficiently, and get them treated efficiently. Methods: Between 2016 and 2020, we implemented an intervention consisting of mass HIV screening of PWID using three annual respondent-driven sampling surveys (RDSS) and a post-intervention evaluation RDSS in community-based organisation (CBO) sites, coupled with peer support to facilitate/improve access to antiretroviral and methadone therapy in Haiphong, Vietnam. The primary outcome was the proportion of identified uncontrolled HIV-positive PWID who achieved viral control. We also estimated the potential effect of the intervention on the proportion of PWID with HIV RNA >1000 copies/mL among all PWID during the study period. Findings: Over the three RDSS, 3150 different PWID were screened, i.e. two-thirds of the estimated population size. They all injected heroin, their median age was of 39 years, 95% were male, 26.5% were HIV-infected, and 78.6% of the latter had HIV RNA ≤1000 copies/mL. Among the 177 PWID identified with an unsuppressed viral load, 73 (41.2%) achieved viral suppression at the final visit. HIV viremia decreased from 7.2% at baseline to 2.9% at the final RDSS (p<0.001). Up to 42% of this observed reduction may be explained by the intervention, in the absence of any external intervention targeting PWID during the study period. Interpretation: Mass community-based screening using RDSS coupled with CBO support is a powerful tool to rapidly identify untreated HIV-positive PWID and (re)link them to care. Funding: NIDA (USA) and ANRS (France).

Alarming Tuberculosis Rate Among People Who Inject Drugs in Vietnam.

BACKGROUND: The tuberculosis (TB) epidemic is not homogeneous in the general population but presents high-risk groups. People who inject drugs (PWID) are such a group. However, TB among PWID remains largely undocumented. Our goal was to assess the prevalence of TB and the risk factors associated with TB among PWID in Vietnam. METHODS: We implemented a cross-sectional survey among 2 community-based cohorts of human immunodeficiency virus (HIV)-positive and HIV-negative PWID in Hai Phong. Participants were screened for TB using questions on TB symptoms. Those who reported any symptom were accompanied by peers to the TB clinic for chest x-ray. If the latter was abnormal, a sputum was collected to perform an Xpert MTB/RIF test. RESULTS: A total of 885 PWID were screened for TB. For both cohorts, most PWID were male (>90.0%), with a median age of 42 years. Beside heroin injection, 52.5% of participants reported smoking methamphetamine, and 63.2% were on methadone. Among HIV-positive PWID (N = 451), 90.4% were on antiretroviral therapy and 81.6% had a viral load <1000 copies/mL. Using a complete-case analysis, the estimated TB prevalence was 2.3% (95% confidence interval [CI], 1.0-4.5) and 2.1% (95% CI, 0.8-4.2) among HIV-positive and HIV-negative people, respectively. Living as a couple, arrest over the past 6 months, homelessness, and smoking methamphetamine were independently associated with TB but not HIV infection. CONCLUSIONS: In the context of very large antiretroviral therapy coverage, this extremely high rate of TB among PWID requires urgent actions.