Hepatitis Prevalence Among Key Populations in Nigeria: A Scoping Review

Nigeria faces a high burden of viral hepatitis, with key populations (KPs) such as sex workers, men who have sex with men (MSM), transgender people, people who inject drugs (PWIDs), and people in prisons. The study aims to review existing evidence on hepatitis among KPs in Nigeria, evaluate study quality, highlight knowledge gaps, and guide public health policy. We conducted a scoping review following the Arksey and O’Malley framework and Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews guidelines. Six databases and gray literature were searched for studies on hepatitis prevalence among KPs in Nigeria (2008–2025). Two independent reviewers screened and extracted data, and study quality was assessed using adapted Joanna Briggs Institute criteria. From 1,270 records screened, 25 studies were included, covering five KP groups in 12 Nigerian states. Hepatitis B virus (HBV) prevalence ranged from 4.0% among sex workers in Enugu to 23.0% in prisons, with MSM and transgender people showing 10.0% in Abuja and Lagos. PWID recorded 6.6– 7.8% HBV and 2.3–3.3% hepatitis C virus (HCV) prevalence, while prisons carried the highest burden. Northern Nigeria showed major data gaps despite higher population prevalence. Methodological weaknesses were found in 68% of studies, with limited evidence for HCV (32%), transgender populations (12%), and rural groups (8%). KPs in Nigeria, particularly prisoners, face a higher hepatitis burden than the general population. There are major evidence gaps on HCV, transgender groups, and rural areas, highlighting the need for more research, wider surveillance, and integrated human immunodeficiency virus-hepatitis services.