HIV treatment can reduce transmission risk by 92%
Benefit best in HIV patients with CD4 counts less than 200 per µl
Thursday, 27 May 2010
Antiretroviral treatment reduced HIV transmission risk by 92% in heterosexual couple, according to new research.
The findings published Online First and in an upcoming Lancet shows that in patients on antiretroviral therapy (ART), there was a 92% lower risk of transmitting HIV to their sexual partners.
The greatest benefit of ART in reducing HIV transmission was among HIV-infected persons with CD4 counts less than 200 per µl. Additionally, the investigators found that among HIV-infected people with CD4 counts above 200 per µl, HIV transmission rates were highest among those with a viral load above 50, 000 copies per ml, suggesting that targeting this group could be an effective way to achieve further population-level reductions in HIV.
In this study, which was funded mostly by the Bill & Melinda Gates Foundation, HIV-infected individuals and their HIV negative partners were enrolled. The HIV-1 infected participants had CD4 counts of 250 cells per μL or greater and did not meet national guidelines for ART (typically at CD4 counts less than 200 per μL). During 24 months of follow-up, CD4 counts were measured every 6 months and ART was initiated if the person’s CD4 cell count fell below 200. Uninfected partners were tested for HIV-1 every 3 months. The primary outcome of the study was HIV-1 transmission between the partners which was identified through genetic analysis. Rates of HIV-1 transmission were compared by ART status of infected participants.
Author, Dr Deborah Donnell, of the International Clinical Research Center, University of Washington and colleagues, said:"Targeting of HIV-1 infected individuals with high plasma HIV-1 concentrations could achieve maximum HIV-1 prevention benefits of ART. Development of inexpensive point-of-care tests for plasma HIV-1 concentration could allow ART provision to be targeted to patients with high CD4 cell counts and high plasma HIV-1 concentrations.
"The greatest priority for ART provision for both treatment and prevention of HIV-1 coincides in patients with CD4 cell counts lower than 200 cells per μL. As countries strategise for optimum use of resources to expand ART provision beyond individuals with low CD4 cell counts, targeting of treatment to those with high plasma HIV-1 concentrations could be a cost-effective strategy to achieve maximum population-level reductions in HIV-1 transmission, as a step toward universal ART provision to all patients with HIV-1."