Molecular Epidemiology of HIV-1 Subtypes among HIV-positive individuals in Anambra State, Nigeria

Abstract

Aims: The study aimed to describe the molecular epidemiology of HIV-1 Subtypes among HIV- positive individuals in Anambra State. Study design:  Cross sectional study. Place and Duration of Study: Department of Microbiology, Nasarawa State University, Keffi, Nnamdi Azikiwe University Teaching Hospital (NAUTH), Nnewi; St. Charles Borromeo Specialist Hospital (SCBSH), Onitsha; and Chukwuemeka Odumegwu Ojukwu University Teaching Hospital (COOUTH), Awka between February 2023 to March 2024. Methodology: Samples were collected from 200 HIV/AIDS-positive participants attending Antiretroviral Therapy (ART) clinic at Nnamdi Azikiwe University Teaching Hospital (NAUTH), Nnewi; St. Charles Borromeo Specialist Hospital (SCBSH), Onitsha; and Chukwuemeka Odumegwu Ojukwu University Teaching Hospital (COOUTH), Awka. Blood samples were obtained for HIV-1 screening using rapid testing and western blot assays to detect HIV-1-specific antibodies, followed by genotyping and phylogenetic analysis. A structured questionnaire was administered to gather socio-demographic data. Results: This study found a 96.5% HIV-1 prevalence in Anambra State, with four major HIV-1 subtypes discovered, of which Subtype C (49.7%) and CRF02_AG (26.9%) were predominant. The 40–49 age group showed the highest subtype prevalence, with females comprising the majority of infections. High viral suppression (71.4–96.2%) and preserved immune function (66.7–78.8% with CD4 ≥500 cells/mm³) reflect effective ART. Phylogenetic analysis confirmed Subtype B, C, CRF01_AE, and CRF02_AG circulation, with strong clustering to Belgian reference strains. Targeted interventions are needed to address the high prevalence and sustain epidemic control. Conclusion: These findings underscore the need for intensified and targeted screening and prevention programs, particularly for women and middle-aged adults. Gender-sensitive interventions and community-based adherence support should also be prioritized to sustain ART success and advance HIV epidemic control in Anambra State.