[[Image:Ro0304F8Treponema.jpg|thumbnail|175px|right|A [[Centers for Disease Control and Prevention]] analysis suggested that approximately 64 percent of all adult primary and secondary syphilis cases in 2004 were among men who have sex with men.]] | [[Image:Ro0304F8Treponema.jpg|thumbnail|175px|right|A [[Centers for Disease Control and Prevention]] analysis suggested that approximately 64 percent of all adult primary and secondary syphilis cases in 2004 were among men who have sex with men.]] |