High rates of unprotected sex occurring among HIV-positive individuals in a daily diary study in South Africa: the role of alcohol use

Objectives: The objectives of this study were to assess the prevalence of unprotected sex and to examine the association between alcohol consumption before sex and unprotected sex among HIVpositive individuals in Cape Town, South Africa. Methods: For 42 days, daily phone interviews assessed daily sexual behavior and alcohol consumption. Logistic and Poisson generalized estimating equation models were used to examine associations between alcohol consumption before sex and subsequent unprotected sex. Results: During the study which yielded 3035 data points, 58 HIVpositive women and 24 HIV-positive men drank an average of 6.13 drinks when they drank and reported 4927 sex events, of which 80.17% were unprotected. More than half (58%) of unprotected sex events were with HIV-negative partners or with partners with unknown HIV status. Extrapolating from the data using likelihood of infection per act estimates, we calculated that an estimated 2.95 incident HIV infections occurred during the study. Drinking alcohol before sex by the female partner or the male partner, or by both partners increased the proportion and number of subsequent unprotected sex events. However, these associations held only when the quantity of alcohol consumed corresponded to moderate or higher risk drinking. Conclusions: Among HIV positive individuals, engaging in moderate or higher risk drinking before sex increases the likelihood and rate of unprotected sex. Prevention efforts need to address reducing alcohol-involved unprotected sex among HIV-positive persons.