Yaws and other endemic treponematoses

Epidemiological situation

Situation and trends

Yaws is a chronic skin infection caused by the bacterium Treponema pallidum subspecies pertenue. This organism belongs to the same group of bacteria that causes venereal syphilis; the available serological tests cannot distinguish between the two diseases. Yaws primarily affects children aged under 15 years who live in poor communities in warm, humid and tropical forested areas of Africa, Asia, Latin America and the Pacific islands. Treatment with a single-dose of azithromycin cures the disease.

A review of the historic documents from 1950s shows that over 90 countries and territories were endemic for yaws. WHO provided technical assistance to 46 of these countries between 1952–1964.

Since 1990, reporting of yaws to WHO is not mandatory and therefore the data availability may be limited. Only 14 out of the 90 countries and territories have recent data on yaws based on the routine surveillance system; however, these figures may just be an indication of the presence of the disease and not its full extent. Ghana, Papua New Guinea and the Solomon Islands report over 10 000 cases per year. Ecuador and India appear to have interrupted transmission.

Distribution of yaws, worldwide, 2012

More information

Country-specific information or data on yaws (2008–2012) is provided for each WHO region.