Editing Yaws (section)

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{{Other uses|Yaw (disambiguation)}}
{{Redirect|Parangi|the village in Iran|Parangi, Iran}}
{{Use dmy dates|date=August 2022}}
{{Infobox medical condition
| name            = Yaws
| image           = Yaws 01.jpg
| caption         = Nodules on the elbow resulting from a ''Treponema pallidum pertenue'' bacterial infection
| field           = [[Infectious disease (medical specialty)|Infectious disease]]
| synonyms        = Frambesia tropica, thymosis, polypapilloma tropicum,<ref>{{cite journal |last1=Maxfield |first1=L |last2=Crane |first2=JS |title=Yaws (Frambesia tropica, Thymosis, Polypapilloma tropicum, Parangi, Bouba, Frambosie, Pian) |date=January 2020 |journal=Stat Pearls |pmid=30252269}}</ref> non-venereal endemic syphilis,<ref name=yaws>{{cite journal |last1=Marks |first1=M |last2=Lebari |first2=D |last3=Solomon |first3=AW |last4=Higgins |first4=SP |title=Yaws |journal=International Journal of STD & AIDS |date=September 2015 |volume=26 |issue=10 |pages=696–703 |pmid=25193248 |doi=10.1177/0956462414549036 |doi-access=free |pmc=4655361}}</ref> parangi and paru (Malay),<ref name=Philippines/> bouba (Spanish),<ref name=Philippines/> frambösie,<ref name="Bolognia">{{cite book |vauthors=Rapini RP, Bolognia JL, Jorizzo JL |title=Dermatology: 2-Volume Set |publisher=Mosby |location=St. Louis |year=2007 |isbn=978-1-4160-2999-1}}</ref> pian<ref name="Andrews">{{cite book |vauthors=James WD, Berger TG |display-authors=etal |title=Andrews' Diseases of the Skin: clinical Dermatology |publisher=Saunders Elsevier |year=2006 |isbn=0-7216-2921-0 |oclc=62736861}}</ref> (French),<ref name=Philippines/> frambesia (German),<ref name=Philippines/> bakataw (Maguindanaoan)<ref name=Philippines/>
| symptoms        = Hard swelling of the skin, [[ulcer]], joint and bone pain<ref name=Mit2013/>
| complications   =
| onset           =
| duration        =
| causes          = ''[[Treponema pallidum]] pertenue'' spread by direct contact
| risks           =
| diagnosis       = Based on symptoms, blood [[antibody]] tests, [[polymerase chain reaction]]
| differential    =
| prevention      = Mass treatment
| treatment       =
| medication      = [[Azithromycin]], [[benzathine benzylpenicillin|benzathine penicillin]]
| prognosis       =
| frequency       = 46,000–500,000<ref name=Mit2012/><!-- cases per what? Year? -->
| deaths          =
}}
<!-- Definition and symptoms -->
'''Yaws''' is a tropical [[infection]] of the [[skin]], [[bone]]s, and joints caused by the [[spirochete]] [[bacterium]] ''[[Treponema pallidum]] pertenue''.<ref name=Mit2013>{{cite journal |vauthors=Mitjà O, Asiedu K, Mabey D |title=Yaws |journal=The Lancet |year=2013 |volume=381 |issue=9868 |pages=763–73 |pmid=23415015 |doi=10.1016/S0140-6736(12)62130-8 |s2cid=208791874}}</ref><ref name=Mit2012>{{cite journal |vauthors=Mitjà O, Hays R, Rinaldi AC, McDermott R, Bassat Q |title=New treatment schemes for yaws: the path toward eradication |journal=Clinical Infectious Diseases |year=2012 |volume=55 |issue=3 |pages=406–412 |format=pdf |pmid=22610931 |doi=10.1093/cid/cis444 |doi-access=free |url=http://cid.oxfordjournals.org/content/55/3/406.long |url-status=live |archive-url=https://web.archive.org/web/20140518070239/http://cid.oxfordjournals.org/content/55/3/406.long |archive-date=18 May 2014}}</ref> The disease begins with a round, hard swelling of the skin, {{cvt|2|to|5|cm|abbr=on}} in diameter.<ref name=Mit2013/> The center may break open and form an [[ulcer]].<ref name=Mit2013/> This initial skin lesion typically heals after 3–6 months. After weeks to years, joints and bones may become painful, [[fatigue (medical)|fatigue]] may develop, and new skin lesions may appear.<ref name=Mit2013/> The skin of the [[hand|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.<ref name=Mit2013/>

<!-- Spread and Diagnosis -->
Yaws is spread by direct contact with the fluid from a lesion of an infected person. The contact is usually nonsexual. The disease is most common among children, who spread it by playing together.<ref name=Mit2013/> Other related [[treponemal]] diseases are [[nonvenereal endemic syphilis|bejel]] (''T. pallidum endemicum''), [[pinta (disease)|pinta]] (''T. carateum''), and [[syphilis]] (''T. p. pallidum''). The appearance of the lesions often diagnoses yaws. Blood [[antibody]] tests may be useful, but cannot separate previous from current infections. [[Polymerase chain reaction]]  is the most accurate method of diagnosis.

<!-- Prevention and Treatment -->
No vaccine has yet been found.<ref name="historical">{{cite journal |last1=Asiedu |first1=Kingsley |last2=Fitzpatrick |first2=Christopher |last3=Jannin |first3=Jean |title=Eradication of Yaws: Historical Efforts and Achieving WHO's 2020 Target |journal=PLOS Neglected Tropical Diseases |date=25 September 2014 |volume=8 |issue=9 |pages=696–703 |issn=1935-2727 |pmid=25193248 |doi=10.1371/journal.pntd.0003016 |doi-access=free |pmc=4177727}}</ref> 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 the spread. Treatment is typically with [[antibiotic]]s, including [[azithromycin]] by mouth or [[benzathine benzylpenicillin|benzathine penicillin]] by injection. Without treatment, physical deformities occur in 10% of cases.

<!-- Epidemiology -->
Yaws is common in at least 13 [[tropical countries]] as of 2012.<ref name=Mit2013/> Almost 85% of infections occurred in three countries—[[Ghana]], [[Papua New Guinea]], and [[Solomon Islands]].<ref>{{cite journal |last1=Mitjà |first1=O |last2=Marks |first2=M |last3=Konan |first3=DJ |last4=Ayelo |first4=G |last5=Gonzalez-Beiras |first5=C |last6=Boua |first6=B |last7=Houinei |first7=W |last8=Kobara |first8=Y |last9=Tabah |first9=EN |last10=Nsiire |first10=A |last11=Obvala |first11=D |last12=Taleo |first12=F |last13=Djupuri |first13=R |last14=Zaixing |first14=Z |last15=Utzinger |first15=J |last16=Vestergaard |first16=LS |last17=Bassat |first17=Q |last18=Asiedu |first18=K |title=Global epidemiology of yaws: a systematic review. |journal=The Lancet. Global Health |date=June 2015 |volume=3 |issue=6 |pages=e324-31 |pmid=26001576 |doi=10.1016/S2214-109X(15)00011-X |pmc=4696519}}</ref> The disease only infects humans.<ref name=WHO/> Efforts in the 1950s and 1960s by the [[World Health Organization]]  decreased the number of cases by 95%.<ref name=WHO/> Since then, cases have increased, but with renewed efforts to [[eradication of infectious diseases|globally eradicate]] the disease by 2020.<ref name=WHO/> In 1995, the number of people infected was estimated at more than 500,000.<ref name=Mit2012/> In 2016, the number of reported cases was 59,000.<ref name=WHO2018>{{cite web |title=Number of cases of yaws reported |work=World Health Organization Global Health Observatory |url=https://apps.who.int/gho/data/view.main.NTDYAWSNUMv |access-date=13 February 2019}}</ref> 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.<ref name=Mit2013/>