In a prospective population-based cohort study conducted in an HIV hyperendemic fishing community (HIV prevalence ~40%), we measured trends in uptake of antiretroviral therapy (ART) and voluntary medical male circumcision (MC), population-level viral load suppression, sexual risk behaviors, and HIV incidence.
From Nov 2011 to Feb 2017, four surveys were conducted in a fishing community on Lake Victoria in Rakai, Uganda as part of an open cohort of all consenting persons aged 15-49. We assessed trends in self-reported ART/MC coverage, population-level HIV viral load suppression (proportion of HIV-positive population with <1000 copies/ml), sexual risk behaviors, and HIV incidence. Poisson multivariate regression with generalized estimating equations and robust variance estimators was used to estimate incidence rate ratios (IRR) and 95%CI of HIV incidence comparing the first to the final survey interval.
5005 individuals participated in the cohort, including 1823 HIV-negative persons with at least one follow-up who contributed 5188 person-years (py) and 134 incident HIV cases. Over the study period, ART coverage increased among all HIV-infected participants from 19% (95%CI: 16-22%) to 81% (95%CI:75-87%), and MC coverage increased among all men from 39% (95%CI: 35-42%) to 63% (95%CI: 59-67%). ART and MC increases occurred in all age groups (Figure). Population-level HIV viral suppression was 78% (95%CI: 72-83%) by study end. Sexual behaviors remained unchanged. Overall HIV incidence declined (Figure) from 3.98/100 py to 1.61/100 py (adjIRR=0.46; 95%CI: 0.27-0.80). Declines in HIV incidence were similar in men (3.78/100py to 1.57/100py) and women (4.27/100py to 1.68/100py). Declines in HIV incidence were observed in persons aged 15-24 years (5.53/100py to 1.87/100py), 25-34 years (3.56/100py to 1.56/100py) and 35+ years (2.96/100py to 1.47/100pys). Overall, HIV prevalence declined from 41% to 36% (p=0.002). Figure: HIV incidence trends; ART and MC coverage over calendar time by age group.
Over about 5 years, HIV incidence significantly declined by approximately 54% as ART and MC coverage increased in a hyperendemic fishing community. These results suggest that HIV treatment and prevention interventions can be rapidly scaled and have substantial population-level impact on HIV incidence in high prevalence settings.