Social injecting and other correlates of high-risk sexual activity among injecting drug users in northern Vietnam

Background: Sexual risk and STDs are relatively high among injecting drug users (IDUs) in Vietnam. We sought to determine characteristics of sexually active IDUs and correlates of high-risk sexual practices among IDUs in Bac Ninh province in northern Vietnam. Methods: We used data collected for a community-based cross-sectional pilot study to identify correlates of recent high-risk sex (>1 sex partner and inconsistent/no condom use in the past year). Factors associated with high-risk sex were identified using logistic regression. Results: Among 216 sexually active male IDUs, one third (n = 72) had engaged in high-risk sex within the last year. IDUs who reported injecting with others more frequently, having someone else inject their drugs at last injection, sharing needles or sharing any injection equipment were more likely to have reported recent high-risk sex. Factors independently associated with high-risk sexual activity were not injecting oneself [AOR: 2.22; 95% CI (1.09-4.51)], and sharing needles in the past 12 months [AOR: 2.57; 95% CI (1.10-5.99)]. Conclusions: IDUs who inject socially and IDUs who share needles are likely to engage in high-risk sexual behaviours and may serve as an important bridge group for epidemic HIV transmission in Vietnam. In addition to messages regarding the dangers of sharing needles and other injection equipment, preventive interventions among newly initiated IDUs should also focus on reducing sexual risk.