A recent cross-sectional study of 1,542 HIV infected people in Soweto, S. Africa, correlates certain sexual risk behaviours against a number of characteristics, including the self-reported HIV status of the partner. Given most risk behaviours by HIV infected people in this area have been reported to be in the context of long-term (heterosexual) relations, the influence on sexual behaviour of partner HIV status might be an important factor – and this study claims to be the first to investigate it.
Two things emerge. First, the influence on behaviour of a partner’s negative or unknown HIV status appears to be slight: for example, the proportion of >2 sex acts in previous fortnight is 16.4% for negative/unknown partner HIV status, as against 19.3% for positive partner HIV status. Second, among the other characteristics surveyed, experience of Anti-Retroviral Therapy (ART) reduces high risk sexual behaviour substantially, even after adjusting for markers of HIV disease progression. (Adjusted odds ratio for correlation of >2 sexual partners over previous fortnight with ART experience was 0.42 for negative/unknown partner HIV status as against 0.59 for positive partner HIV status).
According to the authors, these results bear out the importance of strategies of secondary prevention within partners in long-term relationships, such as the strategies already successfully deployed elsewhere in sub-Saharan Africa, e.g. voluntary counselling and testing (VCT). The duration of relationships in the study is (median) >3 years; yet infected persons, far from adopting appropriate risk adoption strategies, remained unaware in 40% of cases of the partner’s HIV status. But in cases where participants received counselling in the course of ART initiation, this impacted considerably on risk reduction. Taken together, these results suggest the potential benefits of couple-based interventions designed to support risk-reduction strategies such as VCT.

Kartik K. Venkatesh et al., “Sexual Risk Behaviors Among HIV-Infected South African Men and Women with Their Partners in a Primary Care Program: Implications for Couples-Based Prevention”, Aids and Behavior, published online 8th April 2011