Objective  To explore incidence and influencing factors of human immunodeficiency virus (HIV) seroconversion among serodiscordant couples in Xinjiang Uygur Autonomous Region (Xinjiang) and to provide a theoretical basis for implementing intervention on high-risk behavior to prevent HIV transmission among serodiscordant couples.

  Methods  We recruited HIV serodiscordant couples in Xinjiang between January 2010 and March 2015 for a prospective cohort study. A every 3-month follow-up and every 6-month serological test plus interview on high risk behaviors were conducted among the participants of the study. The seroconversion rate by person years was calculated and Cox proportional hazard model was used to examine the influencing factors of HIV seroconversion.

  Results  For a total of 2 496.23 person years′ follow-up upon 1 162 HIV negative individuals among the serodiscordant couples recruited, 42 HIV seroconversions were identified and the seroconversion rate was 1.68/100 person-years. Multivariate analysis revealed that having intercourse more than twice per month during previous 6 months (adjusted hazard risk aHR = 2.48, 95% confidence interval 95% CI: 1.22 – 5.02; P = 0.012) and the propositus′ latest CD4 cell count being less than 200/μL (aHR = 2.88, 95% CI: 1.37 – 6.08; P = 0.006) were the risk factors of HIV seroconversion; whereas, continuous condom using (aHR = 0.32, 95% CI: 0.16 – 0.63; P = 0.003) and being aware of the transmission route of HIV (aHR = 0.20, 95% CI: 0.07 – 0.60; P = 0.004) were protective factors against HIV seroconversion.

  Conclusion  The HIV seroconversion rate is high among serodiscordant couples in Xinjiang, suggesting that condom use and health education on HIVrelated knowledge should be promoted among the serodiscordant couples.