A study of serodiscordant heterosexual couples in Uganda has found that the HIV-positive partner never transmitted the virus to the other if he or she was taking antiretrovirals (ARVs), adding a voice to the expanding chorus of recent research showing that HIV treatment can significantly curb the spread of the virus, aidsmap reports. Unlike the HPTN 052 study, which in 2011 made shockwaves with its finding that ARVs could reduce transmission within serodiscordant heterosexual couples by 96 percent, this study was not a tightly controlled clinical trail, but a prospective cohort study, reflecting a real world setting.

Publishing their findings in PLOS ONE, researchers analyzed records spanning from 1989 to 2007 of 20,000 Ugandans in 25 villages. The records were a result of researchers' annual visits to households where they would conduct behavioral and demographic surveys and test for HIV, as well as collect any available data about ARV use, viral load and CD4 counts from HIV-positive people.

The researchers examined records for 2,465 heterosexual couples in which both members' HIV status was identified and on whom more than one HIV test had been conducted. The median follow-up time was 2.83 years. At the first home visit, 2,113 of these couples were both HIV negative, 131 (5.3 percent) both had HIV and 221 (9 percent) were serodiscordant. Subsequently, 53 people in the couples without an HIV diagnosis became HIV positive, thus making the couple serodiscordant, and then nine of the second partners were subsequently infected with the virus. In addition, 53 of the HIV-negative partners in the initially serodiscordant couples became HIV positive. Consequently, the study found 62 transmissions within couples identified as serodiscordant at some point during the course of the study.

With 29 person-years on ARVs, none of the HIV-positive partners transmitted to their partners. Meanwhile, among those HIV-positive people not taking drug therapy, there were 62 transmissions, with 843 person-years of follow-up.

However, unlike in the HPTN 052 trial, which used DNA testing to match strains of HIV between partners, the researchers could not prove the actual source of a new infection in the Uganda study.

To read the aidsmap story, click here.

To read the study abstract, click here