Yaws and other endemic treponematoses

Yaws

Picture from "Yaws: Recognition booklet for communities"
Endemic treponematoses

Endemic treponematoses are a group of chronic bacterial infections caused by treponemes. These infections are:

  • Yaws, also known as framboesia or pian, caused by Treponema pallidum subsp. Pertenue;
  • Endemic syphilis, also known as bejel, caused by T. pallidum subs. Endemicum;
  • Pinta caused by T carateum.

All these infections often affect the skin and present skin lesions.

Bejel occurs principally in the Sahel region of Africa and Arabian Peninsula and pinta is restricted only to Latin America.

Yaws

Yaws is the most common of these infections, occurring mainly in poor communities in warm, humid tropical regions of Africa, Asia, Latin America and Western Pacific.

Almost 75% of people affected are children under 15 years, although peak incidence occurs in children between the ages 6–10.

Symptoms

Yaws is transmitted primarily through skin contact with an infected person. A single skin lesion develops at the point of entry of the bacterium after 2-4 weeks. If left untreated, multiple lesions appear all over the body. Although rarely fatal, yaws can lead to chronic disfigurement and disability. Overcrowding, poor personal hygiene and poor sanitation facilitate the spread of the disease.

Treatment

The 11 January 2012 edition of "The Lancet" published findings that a single dose of oral azithromycin is as effective as a single injection of benzathine penicillin. This new finding overcomes the operational difficulties associated with administering an injection and paves the way to tackle yaws through the mass treatment of entire populations at risk.

Elimination to eradication

Experts believe that yaws can easily be controlled and possibly eradicated as the disease occurs only in humans. Past experience has showed that elimination is possible in many countries. More recently, India eliminated yaws with no new cases since 2004. The NTD roadmap Accelerating work to overcome the global impact of neglected tropical diseases – A roadmap for implementation. Executive summary has targeted yaws for eradication by 2020. If successful, it will become the first disease to be eradicated through the use of antibiotics

Yaws in the news

11 April 2013 | Geneva
New trial confirms effectiveness of single-dose oral antibiotic, boosting prospects for yaws eradication
Full article


15 February 2013 | Geneva
Meeting of the International Task Force for Disease Eradication – November 2012, Weekly Epidemiological Record No. 7, 2013, 88, 73–80
Full article


13 February 2013 | Geneva
Yaws seminar
Full article www.thelancet.com


15 January 2013 | Geneva
Meeting on eradication of yaws. CICG, Geneva, Switzerland. 20–22 March 2013
To develop criteria and procedures for certification of yaws eradication.


News archives

Photogallery

Cases of yaws treated with single-dose oral azithromycin
See pictures

Contact

Yaws Eradication Programme:
yaws@who.int