Developments in therapy and diagnosis of yaws and future prospects

Abstract

Yaws, a chronic and debilitating infectious disease caused by Treponema pallidum subsp. pertenue, and closely related to syphilis, although transmitted by skin-to-skin contact, remains an important public health challenge, causing a significant burden of morbidity in children in certain areas of the Pacific and Africa. Recent advances in its diagnosis and treatment have led to an enthusiastic upsurge of activities related to its control, and exciting perspectives of global eradication. Although possibly considered among the most neglected of all neglected diseases during decades, there seems to be now agreement that massive drug administration of the antibiotic azithromycin, coupled with adequate surveillance of foci of transmission could result in its eradication. In this review, we summarize current knowledge regarding the therapeutics of yaws and its diagnosis.

Keywords::

• azithromycin
• benzathine benzylpenicillin
• eradication
• treponematosis
• yaws

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• • Yaws is endemic in rural areas among communities living in overcrowded conditions with poor hygiene.

• • The clinical diagnosis of endemic treponematoses may be difficult because these infections produce lesions that can resemble several other diseases in the tropics; thus, support by laboratory techniques and epidemiologic characteristics is necessary.

• • In the laboratory, the diagnosis of yaws is established via serology. Nontreponemal tests are positive in untreated patients and are a better indication of active disease. A new Dual rapid test adds potential value to standard nontreponemal test because it can be easily performed in the field.

• • For treatment of yaws, we recommend oral azithromycin or injectable benzathine benzylpenicillin (grade 1B).

• • Clinical treatment failure must be confirmed for treponemal infection and if the result is positive, patients should be switched to an alternative regimen.

• • Patients should undergo follow-up nontreponemal testing (where available) at 6 and 12 months. Serological treatment failure can occur and is thought to be caused mainly by reinfection rather than by relapse.

• • Yaws is a potentially eradicable disease since the diagnosis and treatment are relatively straightforward, and the disease is restricted to limited geographical areas.

• • The WHO has set a target of 2020 for global eradication of yaws. The approach consists of a single dose of oral azithromycin (30 mg/kg, maximum 2 g) given to entire populations in endemic areas.

Notice of correction

The original online publication of this article was missing information at the end of the second paragraph on page 1117. This, as well as the necessary reference updating has now been added to the final print and online publication.