Rural Community with High HIV Prevalence in South Africa

Bärnighausen T, Tanser F, Newell ML. Lack of a Decline in HIV Incidence in a Rural Community with High HIV Prevalence in South Africa .

To understand the dynamics of the HIV epidemic and to plan HIV treatment and prevention programs, it is critical to know how HIV incidence in a population evolves over time. Bärnighausen and colleagues used data from a large population-based longitudinal HIV surveillance in a rural community in South Africa to test whether HIV incidence in this population has changed in the period from 2003 through 2007. They observed 563 seroconversions in 8095 individuals over 16,256 person-years at risk, yielding an overall HIV incidence of 3.4 per 100 person-years (95% confidence interval 3.1-3.7). The authors included time-dependent period dummy variables (in half-yearly increments) in age-stratified Cox regressions in order to test for trends in HIV incidence. They first did regression analyses separately for women and men. In both regressions, the coefficients of all period dummy variables were individually insignificant (all p >/= 0.338) and jointly insignificant (p = 0.764 and p = 0.111, respectively). They then did regression analysis using the pooled data on women and men, controlling for sex and interactions between sex and age. Again, the coefficients of the eight period dummy variables were individually insignificant (all p >/= 0.387) and jointly insignificant (p = 0.701). They show for the first time that high levels of HIV incidence have been maintained without any sign of decline over the past 5 years in both women and men in a rural South African community with high HIV prevalence. It is unlikely that the HIV epidemic in rural South Africa can be reversed without new or intensified efforts to prevent HIV infection.

Editors’ note: Changes in HIV prevalence figures are difficult to interpret as they reflect both the incidence of new infections and mortality in people living with HIV. What we really need to know is the trend in HIV incidence as this reflects the effectiveness of prevention programming and predicts eventual treatment demand. The findings from this prospective, longitudinal study are highly disturbing: with a constant, unrelenting incidence of 3.4 per 100 person-years, 15 out of every 100 people who were HIV-negative at the start of the study in 2003 had seroconverted by its end 5 years later. The prevention programmes that have been operating clearly do not reach enough people with effective prevention messages, skills building, and support for changed sexual behaviour norms. Safe male circumcision services, positive prevention programmes, and community mobilisation to address the structural factors underlying risk in this rural KwaZulu-Natal community are additional approaches that deserve immediate attention