Concurrent Partnerships as a Driver of the HIV Epidemic in Sub-Saharan Africa? The Evidence is Limited

Abstract

Little evidence supports the hypothesis that sexual behavior differs dramatically in Africa compared to the rest of the world nor that sexual behavior in Africa is different in countries with high versus low HIV prevalence. And it bears repeating that the most rigorous field studies on this topic did not find evidence for an association between concurrency and HIV prevalence in five diverse African cities or in 22 countries. Theoretical plausibility-provided by the mathematical models-does not provide sufficient evidence to conclude that what could happen is actually what has happened. Without strong data showing that people have more concurrent partnerships in Africa than elsewhere and that places with high levels of concurrency also have high levels of HIV we can only conclude that under certain conditions concurrency may be a significant driver of the HIV epidemics in sub-Saharan Africa. To definitively answer this question additional studies are needed. First improved methods for measuring sexual behavior and particularly partnership duration and overlap are needed. Without a common definition of concurrency it is futile to make valid comparisons across populations and between studies. Second better study designs must be used. Current data comes from cross-sectional and ecological studies only. Longitudinal studies that prospectively measure concurrency and incidence of HIV infection are needed to validly assess whether concurrency causes increased transmission of HIV. Once there is evidence that concurrency is a causal factor that increases the risk of HIV infection it will make sense to measure the effect of population-level concurrency on HIV epidemics. Whether concurrency is a significant driver of the HIV epidemic in sub-Saharan Africa is a question that has yet to be answered. Finally designing prevention interventions around concurrency without a better understanding of the intricacies of the relationship between concurrency and HIV transmission may well not produce the intended result of preventing new HIV infections. (excerpt)