BACKGROUNDTo assess the impact of combination HIV prevention (CHP) on HIV incidence, we analyzed the association between HIV incidence and scale-up of antiretroviral therapy (ART) and medical male circumcision in Rakai, Uganda. Changes in population-level viral load suppression and sexual behaviors were also examined.METHODSBetween 1999 and 2016, data were collected through 12 surveys from 30 communities in the Rakai Community Cohort Study, an open population-based cohort of persons aged 15-49 years. We assessed HIV incidence trends based on observed seroconversion data, self-reported ART and male circumcision coverage, viral load suppression, and sexual behaviors.RESULTSIn total, 33,937 study participants contributed 103,011 person-visits (HIV prevalence ~13%). Follow-up of 17,870 HIV-negative persons contributed 94,427 person-years with 931 seroconversions. ART was introduced in 2004; by 2016 coverage was 69% (72% in women vs. 61% in men, p<0.001). HIV viral load suppression among all HIV-positive persons increased from 42% in 2009 to 75% by 2016 (p<0.001). Male circumcision coverage increased from 15% in 1999 to 59% by 2016 (p<0.001). Persons 15-19 years reporting n 71 ever having sex increased from 30% to 55% (p<0.0001). HIV incidence declined by 42% in 2016 relative to the pre-CHP period prior to 2010 (1.17/100 py to 0.66/100 py; adjIRR:0.58: 95%CI: 0.45-0.76); declines were greater in men (adjIRR=0.46; 95%CI: 0.29-0.73) than women (adjIRR=0.68, 95%CI: 0.50-0.94).CONCLUSIONSIn this longitudinal study, HIV incidence significantly declined with CHP scale-up, providing empiric evidence that HIV control interventions can have substantial population-level impact. However, additional efforts are needed to overcome gender disparities and achieve HIV elimination.

SummaryBackgroundUnderstanding the extent to which HIV burden differs across communities and the drivers of local disparities is critical for an effective and targeted HIV response. We assessed community-level variations in HIV prevalence, risk factors, and treatment and prevention service uptake in Rakai, Uganda.MethodsThe Rakai Community Cohort Study (RCCS) is an open, population-based cohort surveying persons aged 15–49 in 40 communities. Participants are HIV tested and interviewed to obtain sociodemographic, behavioral, and health information. RCCS data from August 2011 to May 2013 were used to classify communities as agrarian (n=27), trading (n=9), or lakeside fishing sites (n=4). HIV prevalence was mapped using Bayesian methods, and variability across and within community classifications was characterized. Differences in HIV risk factors and uptake of antiretroviral therapy and male circumcision between community types were assessed.Findings17,119 individuals were included; 9215 (54%) were female. 9931 participants resided in agrarian, 3318 in trading, and 3870 in fishing communities. There was large variation in HIV prevalence, ranging from 9% to 43% across communities. Fishing communities had a higher median HIV prevalence (41%, range: 37–43%) compared to trading (17%, range: 11–22%) and agrarian communities (14%, range: 9–26%); ART and male circumcision coverage were significantly lower in fishing communities. Self-reported risk behaviors were significantly higher in men compared to women and in fishing communities compared to other community types.InterpretationThere is substantial heterogeneity in HIV prevalence, risk factors, and service uptake across communities within one region of Uganda. These findings underscore the need for local surveillance and have important implications for the design of targeted HIV responses. In particular, the extremely high HIV burden and risk behaviors, and low use of combination HIV prevention in fishing communities make these areas a priority for intervention.

Background International and global organisations advocate targeting interventions to areas of high HIV prevalence (ie, hotspots). To better understand the potential benefits of geo-targeted control, we assessed the extent to which HIV hotspots along Lake Victoria sustain transmission in neighbouring populations in south-central Uganda. Methods We did a population-based survey in Rakai, Uganda, using data from the Rakai Community Cohort Study. The study surveyed all individuals aged 15-49 years in four high-prevalence Lake Victoria fishing communities and 36 neighbouring inland communities. Viral RNA was deep sequenced from participants infected with HIV who were antiretroviral therapy-naive during the observation period. Phylogenetic analysis was used to infer partial HIV transmission networks, including direction of transmission. Reconstructed networks were interpreted through data for current residence and migration history. HIV transmission flows within and between high-prevalence and low-prevalence areas were quantified adjusting for incomplete sampling of the population. Findings Between Aug 10, 2011, and Jan 30, 2015, data were collected for the Rakai Community Cohort Study. 25 882 individuals participated, including an estimated 75•7% of the lakeside population and 16•2% of the inland population in the Rakai region of Uganda. 5142 participants were HIV-positive (2703 [13•7%] in inland and 2439 [40•1%] in fishing communities). 3878 (75•4%) people who were HIV-positive did not report antiretroviral therapy use, of whom 2652 (68•4%) had virus deep-sequenced at sufficient quality for phylogenetic analysis. 446 transmission networks were reconstructed, including 293 linked pairs with inferred direction of transmission. Adjusting for incomplete sampling, an estimated 5•7% (95% credibility interval 4•4-7•3) of transmissions occurred within lakeside areas, 89•2% (86•0-91•8) within inland areas, 1•3% (0•6-2•6) from lakeside to inland areas, and 3•7% (2•3-5•8) from inland to lakeside areas. Interpretation Cross-community HIV transmissions between Lake Victoria hotspots and surrounding inland populations are infrequent and when they occur, virus more commonly flows into rather than out of hotspots. This result suggests that targeted interventions to these hotspots will not alone control the epidemic in inland populations, where most transmissions occur. Thus, geographical targeting of high prevalence areas might not be effective for broader epidemic control depending on underlying epidemic dynamics.

National Institute of Mental Health, the National Institute of Allergy and Infectious Diseases, the National Institute of Child Health and Development, the National Institute for Allergy and Infectious Diseases Division of Intramural Research, National Institutes of Health; the Centers for Disease Control and Prevention; the Bill & Melinda Gates Foundation; and the Johns Hopkins University Center for AIDS Research.

No abstract