Peter Schick Newsletter - Heterosexual HIV-1 transmission after initiation of antiretroviral therapy: A prospective cohort analysis. May 27 2010

Donnell, et al. Heterosexual HIV-1 transmission after initiation of antiretroviral therapy: A prospective cohort analysis. Lancet 2010 May 27 2010

HIV Treatment doubles as prevention in Heterosexual couples. Antiretroviral therapy reduce the likelihood of HIV transmission by 92 % among heterosexual discordant couples in Africa. It is well known that providing antiretroviral therapy in HIV-infected individuals reduces the likelihood of HIV transmission, but how strong is the effect with serodiscordant couples, one HIV+and one HIV-. How should antiretroviral therapy be provided to maximize the benefit. A post hoc analysis from the Partners in Prevention HSV/HIV transmission study provides answers.

The study involved 3381 heterosexual serodiscordant couples in Africa. researchers compared transmission rates between the 349 HIV-infected individuals who initiated ART during follow up-(mostly because of pregnancy or low CD4-cell counts_ and the3032 who did not. Of those who initiated ART, 70% achieved viral loads below 2.4 log copies/nk. All study participants were counseled frequently about side effects, safe sex; unprotected sex was reported in only 7& of all follow--up visits.

A total of l03 genetically linked transmission events occurred, but one one was in a couple in which the infected partners was receiving ART. The transmission rate was ..37 per l00 person-years among individuals who initiated.

Among individuals who were not receiving ART, the rate of transmission was highest for those with CD4 counts less than 200: for those with CD4 cell counts greater than 200 cell/mm3, the rate of transmission was highest for those with viral load greater than 50,000 copies/ml.

This study clearly demonstrates that the risk for HIV transmission is highest among individuals with CD4 counts less than 200. Bit it also identifies another high-risk group: patients with CD4 counts greater than 300 who have viral loads greater than 50,000 copiesl/ml.

With the data now showing that ABC for prevention, abstinence, be true to your partner has failed, as has microbicides, vaccines, circumcision. treated infected people with antiretroviral therapy is the best way of preventing HIV infection in discordant couples. This will most likely remain than way until a vaccine is found.