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STD and STI Crisis

Sexually transmitted infections (STIs) are a major global cause of acute illness, infertility, long-term disability and death with serious medical and psychological consequences of millions of men, women and infants. There are over 30 bacterial, viral and parasitic pathogens that have been identified to date that can be transmitted sexually. Quantifying the incidence and burden of these infections is important for planning appropriate interventions and advocating for resources, as necessary.

This report presents global and regional estimates for 2008 of the incidence and prevalence of four curable STIs – Chlamydia trachomatis, Neisseria gonorrhoeae, syphilis and Trichomonas vaginalis – in adults between 15 and 49 years of age. These estimates were generated using the same approach as used to generate the 2005 global estimates (see World Health Organization, 2011, for a detailed description of these methods).

The total number of new cases of the four STIs in 2008 in adults between the ages of 15 and 49 was estimated to be 498.9 million: 105.7 million cases of C. trachomatis, 106.1 million cases of N.  gonorrhoeae, 10.6 million cases of syphilis and 276.4 million cases of T. vaginalis. In addition, at any point in 2008 it was estimated that 100.4 million adults were infected with C. trachomatis, 36.4 million with N. gonorrhoeae, 36.4 million with syphilis and 187.0 million with T. vaginalis.

Select your region of interest for detailed information:



Americas – USA

Eastern Mediterranean


South-East Asia

Western Pacific