Antiretroviral agents (ART) have the potential to prevent HIV transmission by reducing the concentration of HIV in blood and genital secretions. Indeed, mathematical models with favorable assumptions suggest the potential of ART to stop the spread of HIV. Empirical results from ecological and population based studies, and several short term observational studies involving HIV discordant heterosexual couples suggest that ART reduces HIV transmission. A multinational randomized controlled trial (NIH NPTN052) also examining the reliability and durability of ART as prevention in HIV discordant couples is underway. The latter and other studies also consider sexual risk taking behavior, and transmission of HIV resistant variants when ART is used as prevention. Early HIV detection and treatment (“test and treat”) are being considered as an important prevention strategy. In this article, we review the data supporting the use of ART to prevent HIV transmission, and critically examine the public health implications of this strategy
