ABSTRACT
Objective@#To investigate the factors associated with syphilis/HIV infection among men who have sex with men (MSM) maintaining a single sexual partner in Shenzhen.@*Methods@#Respondent driven sampling and snowball sampling method were used to recruit MSM receiving voluntary counseling and testing in Shenzhen Rainbow clinic from 2011 to 2016. Inclusion criteria: aged 18 years and above; reported having one or more anal sexual partners in the recent 6 months. A total of 3 109 men who have sex with men (MSM) were involved in the study. Questionnaire-based interviews were conducted on a one-on-one basis. Data were collected including socio-demographic information, human immunodeficiency virus (HIV) testing history, history of blood donation and drug abuse in the recent two years, self-identified sexual orientation, role in homosexual behavior, ever being money boys (MB) and clients of MB, female sexual partners in the recent 6 months. 5 ml blood samples were taken after questionnaires. Syphilis was screened using toluidine red unheated serum test for the antibody of treponema pallidum and then confirmed by treponema pallidum particle assay. The enzyme-linked immunosorbent assay (ELISA) was used for screening HIV and western blot was used to confirm the HIV screening results. The difference of condom use among MSM between female sexual partners and male sexual partners were compared. Multivariate unconditional stepwise logistic regression model was used to analyze factors associated with syphilis infection and HIV positive among MSM.@*Results@#A total of 3 109 eligible participants with mean (SD) age of 31.49 (8.64) years were enrolled in this study. Among them, 565 cases were infected with syphilis (18.17%), 330 cases were infected with HIV (10.61%), and 165 cases (5.31%) were syphilis co-infected with HIV. 791 (25.44%) reported maintaining a single sexual partners in the recent 6 months. Compared to MSM with multiple sexual partners, the prevalence of syphilis and HIV infection among MSM with a single sexual partner were lower, and the OR (95%CI) were 0.64 (0.51-0.81) and 0.66 (0.49-0.90), respectively.@*Conclusion@#The proportion of fixed single sexual partner was much lower among MSM in Shenzhen. Maintaining a single sexual partners can reduce the risk of syphilis/HIV infection among MSM.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the distribution and factors associated with HIV and syphilis infection among Men who have sex with men blood donors (MSMBD) in Shenzhen.</p><p><b>METHODS</b>A total of 813 MSMBD were recruited using snowball sampling and respondent driven sampling from 2009 to 2012 in Shenzhen. Questionnaire-based interviews were conducted on a one-on-one basis. Data were collected including socio-demographic information, HIV testing history, self-identified sexual orientation, role in homosexual behavior, information about having sex with male sexual partners in the past six months and information about having sex with female sexual partners in the past six months.5 ml blood samples were taken and tested for treponema pallidum and HIV antibodies. Comparisons of syphilis and HIV infection among different years were analyzed by the Cochran-Armitage trend test. Factors associated with syphilis and HIV infection were analyzed by the univariate logistic regression and multivariate unconditional logistic regression.</p><p><b>RESULTS</b>The prevalence of syphilis, HIV, and syphilis-HIV co-infection among 813 participants were 22.0% (179/813), 8.0% (65/813), and 4.2% (34/813), respectively. In the multivariate logistic regression analysis, ever tested for HIV (versus without HIV testing history, OR (95%CI) = 0.369(0.213-0.641)) will decrease the risk of HIV infection among MSMBD in comparison with never tested for HIV (OR (95%CI) = 0.37 (0.21-0.64) ); having five or more anal sexual partners in the past six months and co-infected with syphilis will increase the risk of HIV infection among MSMBD in comparison with having 0-1 sexual partners (OR (95%CI) = 2.04 (1.03-4.06) ) and negative syphilis (OR (95%CI) = 4.52(2.64-7.73)), respectively, bisexual orientation, having 2-4 anal sexual partners and having five or more anal sexual partners in the past six months, using condoms not for every act of anal sex, co-infected with HIV will increase the risk of syphilis infection among MSMBD in comparison with homosexual orientation (OR (95%CI) = 1.60(1.12-2.27)), having 0-1 sexual partner in the past six months (OR (95%CI) = 1.77 (1.09-2.87) and OR (95%CI) = 1.84(1.09-3.08) ) , using condoms for every act of anal sex (OR (95%CI) = 1.61 (1.10-2.36) ) and negative HIV (OR (95%CI) = 4.02 (2.33-6.96)), respectively.</p><p><b>CONCLUSION</b>The prevalence of HIV and syphilis among MSMBD in Shenzhen are much higher with complex influence factors. The relevant government should pay great attention to it and ensure the blood safety.</p>