Investigation of a secondary syringe exchange program for homeless young adult injection drug users in San Francisco, California, USA

This study investigated an HIV prevention program for homeless young adult injection drug users (IDUs) that combined a secondary syringe exchange prog ram (SEP) with community-level activities. Homeless young IDUs were recruit ed from street-based settings in San Francisco, and a structured questionna ire was administered. The secondary SEP operated in a circumscribed geograp hic area, and for analytic purposes respondents were assigned to the interv ention site group if they primarily spent time in this area (n = 67), or th e comparison site group if they primarily spent time elsewhere(n = 55). Alm ost all (96%) intervention site youth had used the secondary SEP in the pas t 30 days and were significantly more likely to regularly use SEP. In bivar iate analysis, comparison site IDUs were more likely to share syringes, reu se syringes, share the cotton used to filter drugs, and use condoms with ca sual sex partners only inconsistently. In multivariate analysis, comparison site remained positively associated with sharing syringes (adjusted odds r atio [AOR], 3.748; 95% confidence interval [CI], 1.406-9.988), reusing syri nges (AOR, 2.769; 95% CI,1.120-6.847), and inconsistent condom use with cas ual sex partners (AOR, 4.825; 95% CI, 1.392- 16.721). This suggests that th e intervention was effective in delivering SEP services to homeless young a dult IDUs, and that IDUs who frequented the intervention site had a lower H IV risk than comparison group IDUs.