The rate of new HIV infections has halved since 2011 in a Ugandan community following large increases in male circumcision, antiretroviral treatment and viral suppression, Joseph Kagaayi of the Rakai Health Sciences Program told the 25th Conference on Retroviruses and Opportunistic Infections (CROI 2018) in Boston on Tuesday.
Dr Kagaayi was presenting results from the Rakai Community Cohort Study, focusing on repeat surveys in one fishing community with a very high prevalence and incidence of HIV infection. This is one of around 50 communities that participates in the Rakai Community Cohort.
The prospective study recruited 5005 individuals residing in the fishing community on Lake Victoria. All were aged between 15 and 49 years.
Surveys conducted between 2011 and 2017 assessed coverage of antiretroviral therapy (ART), rates of voluntary male circumcision, population viral suppression (the proportion of all people with HIV with viral load below 1000 copies/ml), sexual risk behaviour, HIV incidence and overall HIV prevalence.
A total of 1823 participants were HIV-negative at baseline and provided follow-up data. These individuals contributed 5188 person-years of follow-up. During this time, there were 134 incident HIV cases.
Over the study period, the proportion of people taking ART increased fourfold from 19% to 81%. This increase was seen in all age groups, although coverage remained lower in women under the age of 24 and men under the age of 30.
There was also a large increase in the coverage of male circumcision, from 39% to 63%.
By 2017, population viral suppression had increased from 33% to 78%. There was no change in reported sexual risk behaviour.
Overall HIV incidence more than halved from 3.97 per 100 person-years in 2011 to 1.61 per 100 person-years in 2017, a 58% reduction in incidence. Similar declines in incidence occurred in women (62% reduction) and men (55% reduction).
Substantial falls in HIV incidence were recorded in all age groups, especially those aged 15 to 24 years, among whom incidence declined from 5.53 to 1.87 per 100 person-years.
These falls in incidence were accompanied by a substantial fall in overall HIV prevalence, which declined from 41% to 36% over the study period.
The investigators conclude that roll-out of ART and male circumcision was accompanied by a 58% reduction in HIV incidence between 2011 and 2017 in this community with an extremely high HIV prevalence. They note that their findings are amongst the first to show that combination HIV prevention can successfully reduce HIV incidence in a hyperendemic 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,” comment the researchers.