Changing Demography of Genital Chlamydia, Gonorrhea, Genital Herpes, Condyloma, and Syphilis Infections in Japan.

There was an epidemiological correlation in time and space between gonorrhea and genital chlamydia as well as between condyloma and genital herpes. There was, however, no correlation in other combinations, such as, gonorrhea and condyloma, genital herpes and chlamydia, etc. The annual incidence of gonorrhea and that of genital chlamydia were mono-phasic with a peak in 2005-2006. The annual incidence of condyloma and that of genital herpes were biphasic with the first distinct peak in 2004-2006 borne by the younger generation and the second broad peak by the older generation that experienced the first wave. The epidemiology of syphilis was entirely different from the above infections: the incidences of early, late, and asymptomatic syphilis started increasing around 2010, which was associated with a shift of patients' peak age towards the younger generation.