Estimate the population size of transgender women based on the capture-recapture method in Tianjin / 中华流行病学杂志

Objective: To investigate the population size of transgender women (TGW) in Tianjin and analyze the characteristics of their sexual behaviors to provide a basis for AIDS prevention and control. Methods: To estimate the population size of TGW in Tianjin using the capture-recapture method. At the same time, an anonymous questionnaire was collected to conduct a multi-factor logistic analysis of the TGW population's sexual behavior. Results: A total of 213 TGW were investigated. Tianjin's estimated TGW population size was 599 (95%CI: 407-792). Multivariate logistic analysis of the use of condoms consistently showed that compared with TGW without regular sex partners, those with regular sex partners had a lower proportion of consistent condom use (aOR=0.44, 95%CI: 0.23-0.82) and had received HIV tests in the last year were more likely to adhere to condom use than those who had not been tested (aOR=2.73, 95%CI: 1.06-6.99). Conclusion: It is necessary to strengthen HIV mobilization testing among the TGW population and their regular sexual partners to improve condom use.

Analysis on psychoactive substances use in men who have sex with men in Tianjin / 中华流行病学杂志

Objective: To understand the use of psychoactive substances and its related factors in men who have sex with men (MSM) in Tianjin. Methods: A cross-sectional survey was conducted in MSM recruited in Tianjin by snowball sampling from September 2017 to December 2020, the information about their social demographic information, use of psychoactive substances and behavioral characteristics were collected, meanwhile the blood samples were taken from them for HIV/syphilis detections. Multivariate logistic regression was used to explore related factors about psychoactive substances use. Results: A total of 9 218 MSM were included in the study, in whom 43.5% (4 013/9 218) had ever used psychoactive substances, including 92.6% (3 718/4 013)who used Rush and 17.2% (692/4 013) who used multi substances. Multivariate analysis showed that, the OR of psychoactive substances use in MSM who were in Han ethnic group was 0.68 (95%CI:0.51-0.91) compared with those who were in minor ethnic group; the OR of psychoactive substances use in MSM who were married or cohabited, divorced or widowed were 0.65 (95%CI: 0.57-0.71), 0.80 (95%CI: 0.65-0.97) respectively compared with those who were unmarried; the OR of psychoactive substances use in MSM who had the first homosexual sex at age of ≥30 years was 0.57 (95%CI: 0.44-0.74) compared with those who had the first homosexual sex at age of <30 years; the OR of psychoactive substances use in local MSM in Tianjin was 1.12 (95%CI: 1.03-1.23) compared with those who were not local residents in Tianjin; the OR of psychoactive substances use in MSM with education level of college or above was 1.29 (95%CI: 1.12-1.49) compared with those with education level of junior middle school or below; the OR of psychoactive substances use in MSM who had anal sex in the past six months was 1.93 (95%CI: 1.34-2.77) compared with those who had no anal sex; the OR of psychoactive substances use in MSM who had >2 homosexual partners in the last week was 1.62 (95%CI: 1.41-1.87) compared with those who had ≤2 homosexual partners; the OR of psychoactive substances use in MSM who had homosexual commercial sex in the past six months was 1.99 (95%CI: 1.62-2.45) compared with those who had no homosexual commercial sex; the OR of psychoactive substances use in MSM who had sexually transmitted diseases in the last year was 2.39 (95%CI: 1.82-3.12) compared with those who had no sexually transmitted diseases and the OR of psychoactive substances use in MSM who received peer education services in the last year was 1.63 (95%CI: 1.50-1.78) compared with those who received no peer education services. Conclusion: The prevalence of psychoactive substances use is high in MSM in Tianjin, and there are many influencing factors. It is necessary to conduct targeted interventions according to the influencing factors.

HIV infection status in male outpatients in sexually transmitted disease clinics in Tianjin, 2016-2020 / 中华流行病学杂志

Objective: To understand the HIV infection status in male outpatients in sexually transmitted disease (STD) clinics in Tianjin from 2016 to 2020. Methods: According to the sentinel surveillance protocol, continuous cross-sectional studies were conducted between April and June during 2016-2020 to collect the information about the awareness of AIDS related knowledge, related sex behaviors, HIV infection, syphilis prevalence and HCV infection of male STD outpatients in Tianjin with a sample seize of 400 in each sentinel clinic. Results: From 2016 to 2020, a total of 4 000 male STD outpatients were surveyed. The HIV positive rate increased from 1.13% (9/800) to 2.25% (18/800) (trend χ2=14.22, P<0.001), the positive rate of syphilis increased from 9.38% (75/800) to 13.00% (104/800) (trend χ2=7.30, P=0.007) in this population during this period. The overall HCV positive rate was 0.45% (18/4 000). Multivariate logistic regression analysis showed that compared with those who were unmarried, had registered residence in Tianjin, had no temporary sexual behavior in the past 3 months, had no anal sex and had negative syphilis test result, the risk factors of HIV infection in the male STD outpatients included cohabitation (aOR=7.53, 95%CI:2.13-26.62), being from other provinces (aOR=3.64,95%CI:1.58-8.38), having temporary sexual behavior in the past 3 months (aOR=2.24,95%CI:1.03-4.89), having homosexual anal sex (aOR=85.99,95%CI:38.76-190.74) and suffering from syphilis (aOR=6.06,95%CI:3.18-11.56). Conclusion: The detection rates of HIV infection and syphilis in male STD outpatients in Tianjin showed upward trends from 2016 to 2020. Having temporary sexual behavior and anal sex, and suffering from syphilis were the main risk factors of HIV infection in male STD outpatients.

Influencing factors of unprotected anal intercourse among Tianjin male homosexuals who used recreational drugs / 上海预防医学

Objective:To explore the demographic characteristics and sexual behavior of men who have sex with men （MSM） in Tianjin， and to compare these aspects between recreational drug users and non-users. Methods:This research was conducted by Tianjin Centers for Disease Control and Prevention. From July to September 2015， various methods such as simple random sampling and snowball sampling were used to recruit MSM. Information was collected through on-site questionnaire surveys， and laboratory tests were conducted to detect human immunodeficiency virus （HIV） infection status in the research subjects. Statistical description and frequency distribution tests on demographic information and behavioral variables were performed. Results:A total of 410 qualified participants， ranged from 17 to 70 years old， were included. A total of 297 （72.4%） MSM were unmarried， 194 （47.3%） had monthly income over 3 000 yuan， 182 （44.4%） MSM had high school education， and 366 （89.3%） were working full-time. Among all 410 participants， 208 MSM self-reported using recreational drugs. Among them， 140 MSM had used Rush Popper. Influencing factors of unprotected anal intercourse （UAI） among Rush Popper users include： more than 30 years old， average monthly income less than 5 000 yuan， and sex with temporary partners （all P<0.05）. Conclusion:Among MSM in Tianjin， the use of recreational drugs is quite common， and Rush Popper is the most commonly used recreational drug. Therefore， it is necessary to establish and strengthen the relevant laws and regulations for the reduction of Rush Popper circulation among the MSM population.

Survey on recent infection of human immunodeficiency virus among men who have sex with men in Tianjin during 2008-2009 / 中华流行病学杂志

Objective To study the situation of HIV infections among men who have sex with men (MSM) in Tianjin during 2008-2009 and to provide reasonable evidence for intervention strategy.Methods Transect investigations in MSM were conducted three times during 2008-2009.Blood samples were collected and detected to identify the recent HIV infection with IgG-capture BED-enzyme immunoassay (BED-CEIA) before HIV incidence was estimated.Results 1799 specimens were tested and the HIV prevalence rates of each study were 6.7％,8.6％ and 6.2％,while the incidence rates were 2.7％,2.5％ and 2.8％,respectively.The estimated incidence rates among these testees were 5.36％ and 5.52％ per year in 2008 and 2009.Conclusion Results of this study showed that the HIV incidence stabilized at high level among MSM in Tianjin,calling for the effective interventions be taken for HIV/AIDS control and prevention.