This study assessed the prevalence and determinants of herpes simplex virus type 2 (HSV-2)/syphilis co-infection and HSV-2 mono-infection in human immunodeficiency virus (HIV)-positive men who have sex with men (MSM) in China. A cross-sectional study was conducted of 545 HIV-positive MSM in Shenyang between February 2009 and October 2014. Participants underwent physical examinations and serological tests for HSV-2 and syphilis. A multinomial logistic regression was used to identify the risk factors associated with HSV-2/syphilis co-infection and HSV-2 mono-infection. The prevalence of HSV-2 mono-infection, syphilis mono-infection, and HSV-2/syphilis co-infection (95% confidence interval) was 48.6% (44.4-52.8%), 34.3% (30.3-38.3%), and 22.9% (19.4-26.5%), respectively. After controlling within HSV-2/syphilis-seropositive cases, regression analysis revealed that the related factors for HSV-2/syphilis co-infection included age (25-50 vs. ≤ 24 years: adjusted odds ratio [aOR], 4.55; > 50 vs. ≤ 24 years: aOR, 43.02), having regular female sexual partner(s) in the past 6 months (aOR, 0.43), and age at first MSM experience (≤ 18 vs. > 18 years: aOR, 2.59) (all P < 0.05). The high prevalence of HSV-2 mono infection and HSV-2/syphilis co-infection in HIV-positive MSM indicates a high secondary HIV transmission risk. A campaign for detection and treatment of HSV-2 and syphilis is urgently required for HIV-positive MSM in China.
Keywords: herpes simplex virus type 2 (HSV-2); human immunodeficiency virus (HIV); men who have sex with men (MSM); syphilis.