Epidemiology of sexually transmitted diseases. What does it tell us?

Incidence numbers of Neisseria gonorrhoeae, Treponema pallidum and Chlamydia trachomatis differ substantially in different countries at different times. In European countries, the incidence of gonorrhea and of primary and secondary syphilis currently is extremely low. In North American countries gonorrhea incidence declined at a very slow annual rate and syphilis incidence increased. Chlamydial infections show a profile that seems to be delayed by two decades from infections with Neisseria gonorrhoeae. Our efforts in the future should be directed to prevent the resurgence of gonorrhea and syphilis and to achieve the same success with chlamydial infections. Poor populations in developed and developing countries, which have similar demographic, social and economic characteristics, represent one important target group for control programs. Education of young and poor people represent the challenge of the future for sexually transmitted diseases control strategies. Combined strategies also will have an effect on incurable viral STD.