Yaws

For other uses, see Yaw (disambiguation).
"Parangi" redirects here. For the village in Iran, see Parangi, Iran.

Yaws
Other namesFrambesia tropica, thymosis, polypapilloma tropicum,[1] non-venereal endemic syphilis,[2] parangi and paru (Malay),[3] bouba (Spanish),[3] frambösie,[4] pian[5] (French),[3] frambesia (German),[3] bakataw (Maguindanaoan)[3]
Nodules on the elbow resulting from a Treponema pallidum pertenue bacterial infection
SpecialtyInfectious disease
SymptomsHard swelling of the skin, ulcer, joint and bone pain[6]
CausesTreponema pallidum pertenue spread by direct contact
Diagnostic methodBased on symptoms, blood antibody tests, polymerase chain reaction
PreventionMass treatment
MedicationAzithromycin, benzathine penicillin
Frequency46,000–500,000[7]

Yaws is a tropical infection of the skin, bones, and joints caused by the spirochete bacterium Treponema pallidum pertenue.[6][7] The disease begins with a round, hard swelling of the skin, 2 to 5 cm (0.79 to 1.97 in) in diameter.[6] The center may break open and form an ulcer.[6] This initial skin lesion typically heals after 3–6 months. After weeks to years, joints and bones may become painful, fatigue may develop, and new skin lesions may appear.[6] The skin of the palms of the hands and the soles of the feet may become thick and break open. The bones (especially those of the nose) may become misshapen. After 5 years or more, large areas of skin may die, leaving scars.[6]

Yaws is spread by direct contact with the fluid from a lesion of an infected person. The contact is usually of a nonsexual nature. The disease is most common among children, who spread it by playing together.[6] Other related treponemal diseases are bejel (T. pallidum endemicum), pinta (T. carateum), and syphilis (T. p. pallidum). Yaws is often diagnosed by the appearance of the lesions. Blood antibody tests may be useful, but cannot separate previous from current infections. Polymerase chain reaction is the most accurate method of diagnosis.

No vaccine has yet been found.[8] Prevention is, in part, done by curing those who have the disease, thereby decreasing the risk of transmission. Where the disease is common, treating the entire community is effective. Improving cleanliness and sanitation also decreases spread. Treatment is typically with antibiotics, including azithromycin by mouth or benzathine penicillin by injection. Without treatment, physical deformities occur in 10% of cases.

Yaws is common in at least 13 tropical countries as of 2012.[6] Almost 85% of infections occurred in three countries—Ghana, Papua New Guinea, and Solomon Islands.[9] The disease only infects humans,[10] although 18th century French historian Pierre François Xavier de Charlevoix describes it as a disease among geese in the Antilles.[11] Efforts in the 1950s and 1960s by the World Health Organization decreased the number of cases by 95%.[10] Since then, cases have increased, but with renewed efforts to globally eradicate the disease by 2020.[10] In 1995, the number of people infected was estimated at more than 500,000.[7] In 2016, the number of reported cases was 59,000.[12] Although one of the first descriptions of the disease was made in 1679 by Willem Piso, archaeological evidence suggests that yaws may have been present among human ancestors as far back as 1.6 million years ago.[6]

  1. ^ Maxfield L, Crane JS (January 2020). "Yaws (Frambesia tropica, Thymosis, Polypapilloma tropicum, Parangi, Bouba, Frambosie, Pian)". Stat Pearls. PMID 30252269.
  2. ^ Marks M, Lebari D, Solomon AW, Higgins SP (September 2015). "Yaws". International Journal of STD & AIDS. 26 (10): 696–703. doi:10.1177/0956462414549036. PMC 4655361. PMID 25193248.
  3. ^ a b c d e Cite error: The named reference Philippines was invoked but never defined (see the help page).
  4. ^ Rapini RP, Bolognia JL, Jorizzo JL (2007). Dermatology: 2-Volume Set. St. Louis: Mosby. ISBN 978-1-4160-2999-1.
  5. ^ James WD, Berger TG, et al. (2006). Andrews' Diseases of the Skin: clinical Dermatology. Saunders Elsevier. ISBN 0-7216-2921-0. OCLC 62736861.
  6. ^ a b c d e f g h i Mitjà O, Asiedu K, Mabey D (2013). "Yaws". The Lancet. 381 (9868): 763–73. doi:10.1016/S0140-6736(12)62130-8. PMID 23415015. S2CID 208791874.
  7. ^ a b c Mitjà O, Hays R, Rinaldi AC, McDermott R, Bassat Q (2012). "New treatment schemes for yaws: the path toward eradication" (pdf). Clinical Infectious Diseases. 55 (3): 406–412. doi:10.1093/cid/cis444. PMID 22610931. Archived from the original on 18 May 2014.
  8. ^ Asiedu K, Fitzpatrick C, Jannin J (25 September 2014). "Eradication of Yaws: Historical Efforts and Achieving WHO's 2020 Target". PLOS Neglected Tropical Diseases. 8 (9): 696–703. doi:10.1371/journal.pntd.0003016. ISSN 1935-2727. PMC 4177727. PMID 25193248.
  9. ^ Mitjà O, Marks M, Konan DJ, Ayelo G, Gonzalez-Beiras C, Boua B, Houinei W, Kobara Y, Tabah EN, Nsiire A, Obvala D, Taleo F, Djupuri R, Zaixing Z, Utzinger J, Vestergaard LS, Bassat Q, Asiedu K (June 2015). "Global epidemiology of yaws: a systematic review". The Lancet. Global Health. 3 (6): e324-31. doi:10.1016/S2214-109X(15)00011-X. PMC 4696519. PMID 26001576.
  10. ^ a b c Cite error: The named reference WHO was invoked but never defined (see the help page).
  11. ^ Charlevoix PF (1730). Histoire de l'isle Espagnole ou de S. Domingue. Paris: F. Barois. p. 29.
  12. ^ "Number of cases of yaws reported". World Health Organization Global Health Observatory. Retrieved 13 February 2019.