Increased HIV prevention program coverage and decline in HIV prevalence among female sex workers in south India

As one way of assessing the impact of Avahan, the India AIDS Initiative of the Bill & Melinda Gates Foundation, we examined the association between HIV prevention program indicators and changes in HIV prevalence among female sex workers (FSWs) between 2005 and 2009.

We conducted a secondary data analysis from 2 large cross-sectional surveys (2005-2006 and 2008-2009) across 24 districts in south India (n = 11,000 per round). A random-effect multilevel logistic regression analysis was performed using HIV as the outcome, with individual independent variables (from both surveys) at level 1 and district-level FSW-specific program indicators and contextual variables at level 2. Program indicators included their 2006 value, the difference in their values between 2008 and 2006, and the interaction between this difference and study round.

HIV prevalence among FSWs decreased from 17.0% to 14.2% (P < 0.001). This decline varied significantly (P = 0.006) across levels of difference in program coverage (% of FSWs contacted by the program in a given year). Odds ratios comparing HIV prevalence between rounds changed with the level of increase in coverage and were statistically significant with coverage increase ≥ quartile (Q) 1: odds ratio, 0.85 at Q1; 0.78 at Q2; 0.66 at Q3; and 0.51 at Q4.

These findings suggest that increased program coverage was associated with declining HIV prevalence among FSWs covered by the Avahan program. The triangulation of our results with those from other approaches used in evaluating Avahan suggests a major impact of this intervention on the HIV epidemic in southern India.