Editing Yaws (section)

==Treatment==
Treatment is normally by a single [[intramuscular injection]] of long-acting [[benzathine benzylpenicillin]], or less commonly by a course of other antibiotics, such as [[azithromycin]] or [[tetracycline]] tablets.{{citation needed|date=April 2020}} Penicillin has been the front-line treatment since at least the 1960s, but there is no solid evidence of the evolution of [[penicillin resistance]] in yaws.<ref name=advances/>

The historical strategy for the [[eradication of infectious diseases|eradication]] of yaws (1952–1964) was:<ref name=advances/><!--Table repeated verbatim from CC BY 4.0 source by Michael Marks-->
{| class="wikitable"
|-
! Prevalence of clinically active yaws !! Treatment strategy
|-
| Hyperendemic: above 10%  || Benzathine benzylpenicillin to the whole community
(total mass treatment)
|-
| Mesoendemic: 5–10%  || Treat all active cases, all children under 15, and all contacts of infectious cases
(juvenile mass treatment)
|-
| Hypoendemic: under 5%  || Treat all active cases and all household and other contacts
(selective mass treatment)
|}

Benzathine benzylpenicillin requires a [[cold chain]] and staff who can inject it, and there is a small risk of [[anaphylaxis]]. It was also not reliably available during the 2010s; there have been supply shortages.<ref name=advances/>

In the 2010s, a single oral dose of [[azithromycin]] was shown to be as effective as intramuscular penicillin.<ref>{{cite journal |vauthors=Mitjà O, Hays R, Ipai A, Penias M, Paru R, Fagaho D, deLazzari E, Bassat Q |title=Single-dose azithromycin versus benzathine benzylpenicillin for treatment of yaws in children in Papua New Guinea: an open-label, non-inferiority, randomised trial. |journal=The Lancet |date=28 January 2012 |volume=379 |issue=9813 |pages=342–47 |pmid=22240407 |doi=10.1016/S0140-6736(11)61624-3 |s2cid=17517869}}</ref><ref name=advances/> Unlike penicillin, there is strong evidence that yaws is evolving [[antibiotic resistance]] to azithromycin; there are two known mutations in the bacterium, each of which can cause resistance and make the treatment ineffective. This has threatened eradication efforts.<ref name=advances/>

Within 8–10 hours of penicillin treatment, bacteria can no longer be found in lesion biopsies.<ref name=yaws/> Primary and secondary lesions usually heal in 2–4 weeks; bone pain may improve within two days.<ref name=advances/> If treated early enough, bone deformities may reverse and heal.<ref name=yaws/> Primary and secondary stage lesions may heal completely, but the destructive changes of tertiary yaws are largely irreversible.{{citation needed|date=April 2020}}

If lesions do not heal, or RPR test results do not improve, this may indicate treatment failure or re-infection; the treatment is typically repeated.<ref name=yaws/> WHO guidelines say that any presumed treatment failures at 4 weeks require [[macrolide#Resistance|macrolide resistance]] testing.<ref name=WHO/>

<gallery mode="packed" heights="200">
File:Large "moist cauliflower" papillomas on left axilla.jpg|Secondary yaws in the left armpit of a ten-year-old, 2020
File:Yaws papillomas on axilla significantly reduced in size 2 weeks and completely resolved 3-and-a-half months after one-dose azithromycin was taken.jpg|Same person, 2 weeks and 3.5 months after a single-dose azithromycin
File:Yaws treatment.png|Before and two weeks after a single injection of benzathine penicillin, 1950s.
</gallery>