HIV risk taking and risk preventing behaviors in men who have sex with men and women: a respondent-driven sampling study in Shenzhen, China

Men who have sex with men (MSM) has clearly become the predominant route of HIV transmission in China. Due to traditional cultures and values, many MSM have frequent sexual relationship with females. These men who have sex with men and women (MSMW) may bridge and facilitate an expansion of the HIV epidemic from MSM to the general heterosexual population.