Determinants of Differential HIV Incidence Among Women in Three Southern African Locations
Journal of Acquired Immune Deficiency Syndromes
We explored factors associated with differential HIV incidence among women participating in a HIV prevention trial in Harare, Durban, and Johannesburg. The trial had shown no effect of the intervention (diaphragm and lubricant gel) on HIV incidence. Methods: A prospective cohort analysis was conducted of trial participants followed for 12-24 months. Sociodemographic, biological, and behavioral data were collected at baseline and at quarterly visits. Factors associated with HIV incidence were
... V incidence were estimated using multivariable Cox regression models, stratified by study location. Attributable risk was calculated from the adjusted hazard ratios (AHR). Results : There were 309 incident HIV infections among the 4948 women in the analysis. HIV incidence was highest in Durban [6.75/100 person-years; 95% confidence interval (CI): 5.74 to 7.93], lower in Johannesburg (3.33/100 person-years; 95% CI: 2.51 to 4.44), and lowest in Harare (2.72/100 person-years; 95% CI: 2.26 to 3.26). Sexually transmitted infections were important risk factors in Harare [prevalent herpes simplex virus type 2 (HSV2) AHR = 2.56, 95% CI: 1.61 to 4.06; incident HSV2 AHR = 12.60, 95% CI: 2.13 to 21.87; Neisseria gonorrhoeae AHR = 6.82, 95% CI: 2.13 to 21.87] and in Durban (prevalent HSV2 AHR = 1.64, 95% CI: 1.07 to 2.51; N. gonorrhoeae AHR = 4.40, 95% CI: 2.07 to 9.39). In Durban, having multiple partners (adjusted odds ratio (AOR) = 1.78 95% CI: 1.11 to 2.85) and sex although a partner was under the influence of alcohol/ drugs (AOR = 1.51 95% CI: 1.05 to 2.16) significantly increased risk, whereas in Johannesburg, sexual debut ,16 years (AOR = 2.60 95% CI: 1.30 to 5.17) was a strong predictor of HIV acquisition. Discussion: Important differences were seen in drivers of HIV incidence at the 3 study locations. Results from this analysis imply that targeted HIV programing could have a large impact on incident HIV infection in women, and that the most effective approach will likely vary based on knowledge of the local situation/epidemiology.