[Characteristics of HIV sexually transmission and challenges for controlling the epidemic in China].

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.