Needle and syringe exchange programmes and prevalence of HIV infection among intravenous drug users in China.

AIM: To examine the association between needle and syringe exchange programme (NSEP) participation and human immunodeficiency virus (HIV) infection among intravenous drug users (IDUs) in China. DESIGN: Cross-sectional survey study design. SETTING: Six counties with active NSEP were selected from each of the seven provinces with active NSEP sampled, resulting in a sample of 42 counties in China. PARTICIPANTS: Subjects were aged more than 18 years and had injected drugs in the past month before the survey, but were excluded if they were currently enrolled in methadone maintenance treatment in order to avoid mixed effects. MEASUREMENTS: HIV prevalence was the primary measure. Odds ratios (ORs), 95% confidence intervals (CIs) and P-values were calculated to evaluate associations between HIV infection and NSEP participation. FINDINGS: A total of 3494 IDUs were interviewed, of whom 1928 (55.2%) were NSEP attendees (meaning they had attended NSEP at least once in their life-time). The unadjusted HIV prevalence was 13.9% among NSEP attendees and 16.5% among NSEP non-attendees (meaning IDUs who had never used NSEP services). After adjusting for potential confounders and taking into account the variation between counties, NSEP non-attendees were 1.67 times more likely to be HIV-positive compared to NSEP attendees (OR=1.67, CI=1.19-2.32, P=0.0031). CONCLUSIONS: Participation in needle and syringe exchange programmes was associated with a substantially lower risk of HIV infection among intravenous drug users in China. Needle and syringe exchange programmes should be expanded to include those who are needle and syringe exchange programme non-attendees.