Prevalence and phylogenetic characterization of hepatitis C virus among indian men who have sex with men: Limited evidence for sexual transmission

Background: Data from high-income countries suggest increasing hepatitis C virus (HCV) prevalence/incidence among human immunodeficiency virus (HIV)–infected men who have sex with men (MSM), but limited data derive from low-and-middle-income countries. Methods: We recruited 4994 MSM from 5 states across India using respondent-driven sampling. Logistic regression incorporating respondent-driven sampling weights and machine learning feature selection were used to identify correlates of prevalent HCV, and Bayesian phylogenetic analysis was used to examine genetic clustering. Results: The median age was 25 years, the HIV prevalence was 7.2%, and 49.3% of participants reported recent unprotected anal intercourse. The HCV prevalence was 1.3% (95% confidence interval, 1.0%–1.6%; site range, 0.2%–3.4%) and was 3.1% in HIV-positive versus 1.1% among HIV-negative men. HCV infection was significantly associated with injection drug use (odds ratio, 177.1; 95% confidence interval, 72.7–431.5) and HIV infection (4.34; 1.88–10.05). Machine learning did not uncover any additional epidemiologic signal. Phylogenetic analysis revealed 3 clusters suggestive of linked transmission; each contained ≥1 individual reporting injection drug use. Conclusions: We observed a low HCV prevalence in this large sample of MSM despite a high prevalence of known risk factors, reflecting either the need for a threshold of HCV for sexual transmission and/or variability in sexual practices across settings.