Track D Social Science, Human Rights and Political Science

Abstract

BackgroundWe evaluated brief combination interventions to simultaneously reduce sexual and injection risks among female sex workers who inject drugs (FSW-IDUs) in Tijuana (TJ) and Ciudad Juarez (CJ) Mexico during 2008-2010, when harm reduction was expanding in TJ, but not CJ.MethodsFSW-IDUs≥18 years reporting recently sharing injection equipment and unprotected sex with clients participated in a randomized factorial trial comparing four brief, single-session combinations of active motivational-interviewing and didactic interventions focused on negotiating safer-sex in the context of drug use and safer-injection skills. The injection intervention included a video made by FSW-IDUs. Women underwent quarterly interviews and testing for HIV, syphilis, gonorrhea, Chlamydia and Trichomonas. Poisson regression with robust variance estimation and repeated measures ordinal logistic regression via GEE examined effects on HIV/STI incidence and receptive needle sharing frequency, respectively. ResultsOf 599 initially HIV-negative FSW-IDUs (TJ: N=296; CJ: N=303), quarterly retention was≥90%. After 12 months, HIV/STI incidence decreased >50% in the active vs. didactic sex intervention (TJ: AdjRR:0.41, 95%CI: 0.18–0.91, p=0.03; CJ: AdjRR: 0.44, 95%CI: 0.19–0.99, p=0.05)-see tables.In CJ, women receiving active vs. didactic injection risk interventions decreased receptive needle-sharing by 84% vs. 71%, respectively (p=0.05); in TJ, receptive needle-sharing declined by 95%, but was similar in active vs. didactic groups (p=0.54). TJ women reported significant increases in access to syringes and condoms, but CJ women did not-see figure.ConclusionIn both cities, a 30-minute intervention promoting safer-sex in the context of drug use significantly reduced HIV/STI incidence with sustained effects at 12 months. Expanding free access to sterile syringes coupled with brief, didactic education on safer injectionwas both necessary and sufficient in achieving dramatic, sustained injection risk reductions in TJ. In the absence of expanding syringe access in CJ, the injection risk intervention still achieved significant, albeit more modest reductions, suggesting that community-level interventions incorporating harm reduction are more powerful than individual-level interventions for reducing injection risks. Figure 1Plot of proportional odds of higher receptive needle sharing for intervention group by visit. Table 1Intervention effects on HIV/STI incidence after 12 months, excluding women who were HIV-positive or had active STIs at enrollment, TiujanaPredictorAdjusted Relative Risk95% CIIntervention Group (ref-Didactic Sex Rick intervention-Diadactic injection Risk intervention)Active Sex Risk Intervention and Didactic Injection Risk Intervention0.410.18, 0.91Active Injection Risk and Didactic Sex Risk Inetevention0.840.38, 1.84Active Sex Risk Intervention+Active Injection Risk Intervention0.360.15, 0.85=of unprotected sex acts with non-regular clients for month poor to enrollment1.011.01, 1.02Anested during the six months poor to enrollment2.611.38, 4.91 Table 2Intervention effects on HIV/STI incidence after 12 months, excluding women who were HIV-positive or had active STIs at enrollment, Ciudad JuarezPredictorAdjusted Relative Risk95% CIIntervention Group (ref-Didactic Sex Rick intervention+Diadactic injection Risk)Active Sex Risk Intervention and Didactic Injection Risk Intervention0.440.19, 0.99Active Injection Risk and Didactic Sex Risk Inetevention1.150.58, 2.28Active Sex Risk Intervention+Active Injection Risk Intervention1.120.56, 2.25Amount earned per unprotected sex act (USD)1.021.00, 1.05Used cocaine the months poor to enrollment1.660.98, 2.80