Conditional Economic Incentives to Reduce HIV Risks Among Male Sex Workers: Results from a Randomized Pilot in Mexico

We tested the extent to which conditional economic incentives (CEI) motivated self-protection and health-care-seeking behaviors among male sex workers (MSW) in Mexico City. We will present the baseline and follow-up results for MSW, ages 18-30, recruited in Mexico City (n=200). Following baseline assessments, participants were randomized into 4 groups. In Treatment 1 (n=50) participants received a medium conditional incentive ($50 USD/each time) only if they were free of new, curable STIs at months 6 and 12. Treatment 2 (n=50) received a high incentive ($75 USD/each time) only if they were free of new, curable STIs at months 6 and 12. Controls (n=50) did not receive any CEI even if they were free of STIs at months 6 and 12. Participants in the unconditional arm receive a medium incentive ($50 USD at months 6 and 12) regardless of STI status. In addition, everyone received inconvenience fees ($10 USD/each time at baseline, month 6 and month 12). All incentives were given out in the form of supermarket vouchers and were modest enough so that undue risk, such as use of drugs or alcohol, was minimized.

The inclusion criteria were: male, ages 18-30, self-identified as sex worker who has been paid to have sex with other men within the last 6 months; recruited in Mexico City from various sites including Alameda Central, Metro Hidalgo, Zona Rosa, or at Clínica Condesa(largest HIV Clinic in Mexico City with over 7,000 patients). All eligible men took part in a standard one-hour HIV education/information session after completing baseline measures, and before random assignment to a research arm. All received HIV/STI testing; those infected were offered treatment. Chronic STIs, such as HIV and Hepatitis B were tested for, but were not used for the conditional incentives. Any participant that was HIV-positive was allowed to continue in the trial and was referred to treatment as indicated by the Mexico City guidelines.

The main baseline results were as follows: Mean age was 25, 76% were single, 31% completed middle school and 35% completed high school. On average they had 6 sexual partners per week. Mean condom utilization with last three clients was 79%. Most MSW were street-based (51%), followed by hotel-based (28%) and at bars (27%). Most participants had at least one STI (63%): a fifth had active syphilis, one in nine had Chlamydia, and 38% had HIV. The highest median price for transactions in the previous week was USD$42; the lowest median price was USD$21 and the average median price was USD$25. There was evidence of a risk premium: we found a 40% higher transaction price for sex without a condom. There was positive relationship with incentives and scheduled visits for testing and project participation whereby higher incentives were associated with higher participation rates. Data collection on the effects of incentives on STI incidence, condom use, number of partners, and commercial sex transaction prices will be completed in April 2014 and will be presented at the proposed session.