Objective  To examine incidence rates and impact factors of human immunodeficiency virus (HIV) infection among injection drug users (IDUs) in Xinjiang Uygur Autonomous Region (Xinjiang).

  Methods  We recruited HIV-negative IDUs in 6 regions with higher prevalence of HIV infection in Xinjiang from June 2010 to March 2015 for a prospective cohort study. The participants of the study were followed-up every 3-month and were surveyed with a questionnaire interview on drug behavior and HIV antibody test every 6-month.

  Results  Among a total of 1 253 participants, 67 HIV infections were identified during the 3 year′s follow-up of 2 416 person years by the end of March 2015 and the incidence rate of HIV infection was 2.77 per 100 person-years. Multivariate Cox proportional hazards regression model analysis revealed higher risk of HIV infection among Uygur IDUs (hazard ratio HR= 2.80, 95% confidence interval 95% CI: 1.10 – 7.17), IDUs with primary school and lower education (HR = 3.68, 95% CI: 1.30 – 10.39), and IDUs without income (HR = 4.77, 95% CI: 1.36 – 16.71) compared to the IDUs of other ethnic groups, with the high school and higher education, and with the monthly income of 2 000 RMB yuan or more. In contrast to the IDUs having the drug less than one time per week, the IDUs having the drug 1 – 3, 4 – 6, and ≥ 7 times per week had significantly increased HIV infection risk, with the HRs (95% CI) of 11.84 (1.59 – 88.39), 10.70 (1.40 – 81.78), and 32.09 (4.27 – 241.30), respectively. The IDUs sharing needles with others and not knowing the sharer′s HIV infection status had a significantly increased risk of HIV infection (HR = 4.89, 95% CI: 2.48 – 9.65) in comparison with the IDUs not sharing needles with others.

  Conclusion  Both the incidence of HIV infection and high risk behavior relevant to HIV infection are at a high level among intravenous drug users in Xinjiang and the results indicate effective measures for HIV infection control should be implemented in the population.