Manopaiboon, C., Prybylski, D., Subhachaturas, W., et al. International Journal of STD & AIDS (March 2013), pp. 1-5.
Using respondent-driven sampling (RDS) from August to November 2007, the authors aimed to reach venue- and non-venue-based female sex workers (FSWs) in Bangkok, Thailand for a survey to estimate HIV risk behaviors and prevalence. Non-venue-based FSWs had higher HIV prevalence, and overall FSW HIV prevalence was considerably higher than in previous survey estimates (20 percent in the RDS survey versus 2.5 percent in the 2007 sentinel surveillance survey). The RDS method effectively recruited FSWs, and findings suggest that subpopulations of FSWs may not be reached by routine sampling. A total of 707 FSWs were recruited using the cascade model; 98 percent agreed to HIV testing and 97 percent agreed to testing for other sexually transmitted infections (STIs). Twenty-seven percent (n=190) returned for test results. Overall STI prevalence was low. Most FSWs were non-venue-based and 93 percent reported condom use with their last client. Younger age was associated with lower HIV prevalence. In multivariate analysis, a lower price and a current STI remained independently associated with HIV after adjusting for other factors. The Thai Ministry of Public Health adopted the RDS method to supplement routine surveillance activities in areas with many FSWs. The authors concluded that HIV prevention programs in Thailand should be customized to subpopulations of FSWs.