Prevalence and risk factors of HIV, HBV, and HCV among women who inject drugs in five Mozambican cities: a subgroup analysis of a cross-sectional biological and behavioral survey, 2023–2024

Abstract Background Women who inject drugs (WWID) are disproportionately affected by HIV and viral hepatitis, yet data on prevalence and risk factors in Mozambique remain scarce. This study aimed to estimate the prevalence of Human Immunodeficiency Virus (HIV), Hepatitis B surface antigen (HBsAg), and antibodies against hepatitis C virus (anti-HCV) among WWID and to identify associated sociodemographic and behavioral risk factors. Methods This cross-sectional study is a subgroup analysis of WWID from the second round of the Bio-behavioral survey (BBS) among people who injected drugs of any gender, conducted in five Mozambican cities (Maputo, Beira, Tete, Quelimane, Nampula) between July 2023 and March 2024, using respondent-driven sampling (RDS); this analysis focuses on the subsample of 524 WWID recruited within that survey. Participants completed structured questionnaires and underwent rapid testing for HIV, HBsAg, and anti-HCV. RDS-weighted prevalence estimates were calculated for all outcomes. Modified Poisson regression with robust standard errors was used to identify factors associated with HIV infection. Results The weighted prevalence was 28.6% (95% CI: 15.5–41.6) for HIV, 5.3% (95% CI: 3.4–7.3) for HBsAg positivity, and 19.7% (95% CI: 3.1–36.2) for anti-HCV positivity. Unadjusted HIV prevalence peaked among women aged 25–34 years, increased markedly with age and duration of injection and was highest in Maputo City. In adjusted analyses, older age (≥ 35 years vs. 16–17 years; aPR = 11.9; 95% CI: 4.0–35.6), and residence in Maputo were independently associated with HIV infection, while secondary or higher education and absence of recent sexually transmitted infection (STI) symptoms were associated with lower HIV prevalence. Among WWID living with HIV, 85.0% were aware of their status, 86.6% of those aware were on antiretroviral therapy, and 75.7% of those on treatment were virally suppressed. Conclusion WWID in Mozambique face a high burden of HIV and anti-HCV positivity, with marked geographic variation. Gaps in the HIV care continuum, particularly between ART initiation and viral suppression, warrant further investigation into potential barriers to sustained treatment and care. Expanded harm-reduction services, integrated HIV, HBV and HCV testing and treatment, and prevention targeted to high-burden areas are needed.