Sexual and reproductive health

Prevalence and incidence of selected sexually transmitted infections

Chlamydia trachomatis, Neisseria gonorrhoeae, syphilis and Trichomonas vaginalis. Methods and results used by WHO to generate 2005 estimates

World Health Organization, Department of Reproductive Health and Research

Publication details

Number of pages: 36
Publication date: 2011
Languages: English
ISBN: 978 92 4 150245 0 - Web only


Sexually transmitted infections (STIs) are a major global cause of acute illness, infertility, long-term disability and death, with serious medical and psychological consequences to millions of men, women and infants. Over 30 bacterial, viral and parasitic pathogens have been identified to date that can be transmitted sexually.

This document presents the methods and results from a WHO-supported exercise to generate global and regional estimates of the prevalence and incidence of four curable STIs, Chlamydia trachomatis (C. trachomatis), Neisseria gonorrhoeae (N. gonorrhoeae), syphilis and Trichomonas vaginalis (T. vaginalis), in adults between 15 and 49 years of age in 2005, building on the approach used to generate estimates in 1995 and 1999.