HIV, hepatitis B & C in people who inject drugs in India: A systematic review of regional heterogeneity & overview of opioid substitution treatment

Background & objectives: This systematic review evaluates the human immunodeficiency virus (HIV), hepatitis C virus (HCV) and hepatitis B virus (HBV) burden among people who inject drugs (PWIDs) in India. In addition, we selectively examined research on opioid substitution treatment (OST)-related services due to their role in antiviral treatment uptake and adherence. Methods: Data were sourced from peer-reviewed and government publications between 1991 and September 20, 2023, searched in MEDLINE, Scopus and EBSCOhost. English language studies reporting weighted prevalence or raw numbers and recruitment sites were included for review. Quality was assessed using the Joanna Briggs Institute tool. Data synthesis was done in graphs and tables. Results: We included 50 reports, yielding 150 HIV, 68 HCV and 24 HBV prevalence estimates across India, revealing significant regional heterogeneity. Notably, 16 States had a single community-based HIV estimate, and 19 States had limited or no HCV data. The highest HIV and HCV prevalence was in Manipur (74.7% and 97.5%, respectively) in 1996. Recent spikes included 50.2 per cent HIV prevalence in Punjab (2010) and 73 per cent HCV in Uttar Pradesh (2021). Nationally, OST coverage in 2020 was under five per cent, with some northeast, north and central States exceeding this, but most others were falling below two per cent. No studies on the cost-effectiveness of directly observed treatment models for OST were identified. Interpretation & conclusions: There is a lack of sufficiently granular and generalizable estimates for HIV prevalence and any estimates for HCV and HBV among PWIDs in large parts of the country. Community-based representative studies are required to quantify the prevalence and severity of these diseases and allocate resources.