HIV incidence and risk factors in Chinese young men who have sex with men--a prospective cohort study.

Objectives: To assess HIV incidence and its associated risk factors among young men who have sex with men (YMSM) in urban areas, China.

Design: The study used a prospective cohort study design and standard diagnostic tests.

Methods: A twelve-month prospective cohort study was conducted among YMSM (18-25 years old) in 8 large cities in China.

[Syphilis incidence and its risk factors in a cohort of young men who have sex with men].

Objectives: To investigate the incidence of syphilis infection and to determine the risk factors related to syphilis infection among young men who had sex with men (YMSM), which were documented for developing effective intervention to prevent sexually transmitted diseases among YMSM.

Methods: A cohort study was conducted in 8 cities (Beijing, Shanghai, Kunming,Guiyang, Chongqing, Chengdu, Urumqi and Nanning) from May to December, 2009. A total of 1 037 syphilis-negative YMSM aged 18-25 were enrolled in the cohort and the two follow-up surveys were carried out every six months.

[The unprotected sexual behaviors and its influencing factors among HIV-infected men who have sex with men in Shanghai, China].

Objective: To investigate the sexual partners and sexual behaviors among HIV-infected men who have sex with men (MSM) and to examine the factors related with high risky sexual behaviors.

Methods: A total of 200 HIV-positive MSM participants were recruited using "snowballing" sampling from June to December in 2010 in Shanghai. Participants completed the questionnaire which included social demographic characteristics, sexual behaviors with male and female sexual partners in the past 6 months, alcohol consumption, alkyl nitrite use, illegal substances use and depression and anxiety symptoms, etc.

[Prevalence of HIV infection and sexual behaviors with both men and women among currently married men who have sex with men].

Objective: To find out the status of HIV infection, sexual behaviors with both men and women as well as condom use among currently married men who have sex with men (MSM) so as to document for HIV intervention targeting this sub-population, in Beijing, Chengdu, Harbin and Zhengzhou cities.

Methods: "Snowballing" sampling method was used to recruit subjects in four cities. Participants were investigated by anonymous questionnaire containing demographics, sexual orientation, both homosexual and heterosexual behaviors and condom use during the past 6 months.

[The prevalence of HIV infection and sexual behaviors among men who have sex with men and women in Chengdu and Guangzhou, China].

Objective: To understand the status of HIV infection and sexual behaviors with men and women among men who have sex with men and women (MSMW) and documented for HIV epidemic among men who have sex with men to the general population.

Methods: 300 participants were recruited by using "snowballing" sampling in Chengdu and Guangzhou, respectively. Participants completed the questionnaire and HIV test.