Aim: To determine prevalence of HIV-1, risk behaviours and demographic characteristics associated with HIV-1 infection among drug users in China based on the national second generation surveillance on drug users in 2005.

Methods: National HIV/AIDS second generation surveillance is a routine work in China; the data on drug users in 2005 were analysed; HIV-1 antibody status was obtained from blood tests; demographic and behavioural data were collected through standardized interviews. In total, 6539 records from 21 surveillance sites were obtained. After data cleaning, a total of 5890 records were included in the analysis. Logistic regression was used to analyse independent association between HIV-1 status and risk behaviours.

Results: HIV-1 antibody prevalence was 5.0 percent, with large regional differences. 52.7 percent drug users in this study once injected drug, HIV-1 antibody prevalence was 6.6 percent among injecting drug users. Syphilis antibody prevalence was 2.8 percent. Based on logistic regression analysis, demographic and behavioral factors significantly associated with HIV prevalence were: minority versus Han-Chinese (OR 4.10; 95 percent CI 3.03-5.55; p<0.001), education <=9 years versus >9 years (OR 1.61; 95 percent CI 1.20-2.15; p=0.001), injecting drugs without needle-sharing versus not injecting (OR 2.49; 95 percent CI 1.77-3.52; p<0.001), injecting drugs with needle-sharing versus not injecting (OR 4.44; 95 percent CI 3.19-6.19; p<0.001).

Conclusion: Prevalence of HIV-1 infection among drug users in China is relatively high (5 percent) and the risk of HIV-1 infection is associated predominantly with minority status, education equal or smaller than 9 years, and injecting drug use. Special interventions among drug users in China are warranted.