Epidemiology of HIV in Remote Equatorial Regions of Cameroon: High Prevalence in Older Adults and Regional Disparities

Data on HIV prevalence in remote, rural communities of Cameroon are scarce despite the country's high HIV-1 group M diversity. This study assessed HIV seroprevalence and socio-demographic determinants in four regions of the equatorial rainforest location of the country. A cross-sectional survey was conducted among 5631 individuals in rural communities of the Centre, East, Littoral, and South regions. HIV testing was performed, and socio-demographic data were collected. Prevalence ratios (PRs) and adjusted prevalence ratios (aPRs) were estimated using bivariate and multivariate analyses (negative log-binomial model with generalised estimating equations, GEEs). Overall, HIV prevalence was 3.4% (95% CI: 2.9-3.9%) in individuals aged 15-49 years and 4.9% in those aged ≥50 years. Women had higher prevalence than men (4.5% vs. 3.0%, aPR = 1.53, 95% CI: [1.12-2.08], <i>p</i> = 0.007) and also higher HIV prevalence among individuals aged 50-54 years compared to those aged 15-19 years (5.5% vs. 1.8%, aPR = 2.76, 95% CI: [1.24-6.15], <i>p</i> = 0.013). The South region recorded the highest prevalence (5.2%, aPR = 1.82, 95% CI: [1.04-3.18], <i>p</i> = 0.035) compared to the Centre region with the lowest (2.3%). Divorced/separated/widowed individuals (10.2%) had increased risk (aPR = 1.70, 95% CI: [0.80-3.58], <i>p</i> = 0.165) compared to single individuals (3.2%). HIV remains a significant public health concern in remote, rural Cameroon, with a disproportionate impact on older adults and women. Surveillance should extend beyond the traditional 15-49-year age range, and targeted prevention is needed for high-prevalence regions and older populations to curb ongoing transmission.