Characteristics of HIV sexually transmission and challenges for controlling the epidemic in China / 中华流行病学杂志

Sexual transmission became the major mode of HIV infection in this country and accounted for 95% of the newly diagnosed cases, 67% and 28% of heterosexual and male homosexual infections, respectively, in 2016. Heterosexual transmission was mostly reported in South-west while male homosexual transmission in North-east and major metropolitan areas. Elderly and young students became the two special groups of people with increased reported HIV cases in the past years, with major modes of transmission as both heterosexual and homosexual. HIV testing and treatment of all HIV infections have been national control strategies and implemented and have significantly reduced HIV sexual transmission among sero-discordant couples. However, about one-third HIV infections remained undiagnosed. HIV infection through sexual transmission will remain a challenge in the years to come.

Application of Bernoulli Process Model fitting the effect of intervention measures on sexual transmission among HIV sero-discordant couples / 中华流行病学杂志

Objectives: To undersand the outcomes of major intervention measures on sexual transmission among HIV sero-discordant couples. Methods: Bernoulli Process Model was applied to model the major influencing factors of HIV transmission among HIV sero-discordant couples. The major influencing factors appeared as consistent condom use, antiretroviral therapy, frequency of sexual behavior. These parameters were from the HIV sero-discordant couples in 30 counties in 4 provinces (Guangxi Zhuang Autonomous Region, Yunnan Province, Xinjiang Uygur Autonomous Region and Henan provinces) from January 1, 2011 to December 31, 2012. According to the main factors, modeling-intervention strategies and measures on reduction HIV transmission among serodiscordant couples were formed. Results: Data from the present proportion of consistent condom use (85%) modeling and the coverage of antiretroviral treatment (60%) showed that, the proportion of cumulative seroconversion among the spouses was 1.76%. Results from the sensitivity analysis on modeling the consistent condom use and the antiretroviral treatment showed that, when the coverage of antiretroviral treatment was as 90% and the proportion of consistent condom use increased from 50% to 90%, with 80.7% of the risk of spouse seroconversion could be reduced. Or, when the proportion of consistent condom use was as 90% and the coverage of antiretroviral treatment increased from 50% to 90%, with 64.5% of the risk of spouse seroconversion could be reduced. Conclusions: With measures as consistent condom use plus provision of timely antiretroviral therapy to HIV positive index spouses, the risk of sexual transmission among sero-discordant couples could be greatly reduced.

Acceptability of HIV testing using oral quick self-testing kit in men who have sex with men / 中华流行病学杂志

Objective: To evaluate the acceptability of oral quick HIV self-testing in men who have sex with men (MSM). Methods: From April 2013 to April 2014, MSM in Beijing and Nanning of China were recruited for an observational study including baseline survey and follow-up, including questionnaire survey, oral HIV self-testing and clinic-based HIV confirmation testing. The sensitivity and specificity of oral quick self-testing were evaluated through comparing the results of oral quick testing with blood testing. The acceptability and associated factors were evaluated by logistic model. Results: A total of 510 MSM were recruited at baseline survey and 279 accepted follow-up. The sensitivity of the oral self-test was 86.00% (43/50) and specificity was 98.23% (445/453) at baseline survey. At baseline survey, 78.63% (401/510) of the MSM showed willingness to use oral quick HIV self-testing. The associated factors included unprotected anal intercourse with a regular male partner in the past 6 months (aOR=0.30, 95%CI: 0.10-1.00) and preference of oral quick HIV self-testing (aOR=7.32, 95%CI: 1.61- 33.31). At baseline survey, 34.51% (176/510) of the MSM reported that oral quick HIV self-testing was the preferred testing method rather than blood testing, which was associated with their birth places-urban area. Conclusion: The acceptability of oral quick HIV self- testing in MSM in the two cities was high.

Changes of proportion regarding consistent condom use and syphilis infection among low-fee female sex workers aged 35 and above / 中华流行病学杂志

Objective: To investigate the changes of proportion on both consistent condom use and syphilis infection among low-fee female sex workers aged 35 and above (LFSW), in order to provide evidence for targeted intervention strategies. Methods: A total of six cities-Liuzhou city and Pingnan couty of Guigang city of Guangxi Zhuang Autonomous Region, Jinghong city of Xishuangbanna Dai autonomous prefecture and Dali city of Dali Bai autonomous prefecture of Yunnan province, Zhangjiajie city and Jianghua Yao autonomous county of Yongzhou city Hunan province were involved in this study, with 60 eligible participants needed in each city, estimated through a pre-study. The first cross-sectional survey was completed from October 2012 to January 2013. Face-to-face questionnaire interview was carried out to collect information on socio-demography, work-related information and condom use situation. Blood was collected for syphilis testing. The second cross-sectional survey was carried out from June to September, 2015 under the same procedure. Results: A total of 371 and 403 eligible participants were included in the first and second survey, respectively. When comparing the two surveys, we noticed that the average age showed a slight change, from 42.4 years to 43.8 years old (t=3.537, P<0.001) and the average price for every commercial sex exchange increased from 36.8 RMB to 49.5 RMB (t=11.961, P<0.001). In the first survey, 46.9% (174/371) of the participants had more than two years of experience working as LFSW, compared to 61.3% (247/403) in the second survey (χ(2)=16.125, P<0.001). Also, 46.9% (174/371) of the participants consistently used condoms with clients in the past month in the first survey versus 64.3% (259/403) (χ(2)=23.641, P<0.001) in the second one. Rates of syphilis infection were found from 15.9% (59/371) in the first survey reduced to 7.2% (29/403) in the second survey (χ(2)=14.533, P<0.001). Conclusion: Compared with the first survey, the proportion of consistent condoms use showed an increase. Although the proportion of syphilis infection decreased in the second survey, the scope did not meet the criteria on syphilis, set by the government. Targeted intervention strategies on condom promotion and syphilis control should be implemented consistently in this population.