Increase in human immunodeficiency virus and syphilis prevalence and incidence among men who have sex with men, vietnam 2015 - 2020.

Despite prevention efforts and improvements in some risk indicators, consecutive cross-sectional sampling results provide evidence of increasing incidence of HIV and syphilis among MSM in Vietnam, especially outside the major cities. Aggressive HIV prevention and treatment services can be expanded while conducting deeper investigations into the causes of these increases.