Accelerating yaws eradication: antibiotic added to WHO’s essential medicines list
9 June 2017 | Geneva –– The World Health Organization (WHO) has added azithromycin to its 2017 Model List of Essential Medicines. Azithromycin is a common antibiotic used to treat bacterial infections, including yaws.
“The inclusion of azithromycin in WHO’s list for the treatment of yaws will greatly facilitate access to the medicine and enhance the implementation of eradication programmes,” said Dr Kingsley Asiedu, Medical Officer in charge of yaws eradication in the WHO Department of Control of Neglected Tropical Diseases.
The latest (20th) List groups azithromycin under a “Watch Group” that includes antibiotic classes with greater potential to develop resistance. WHO therefore recommends azithromycin to be used as a first- or second-choice treatment for a specific, limited number of indications and that it should be subject to monitoring and continued evaluation for resistance.
“As with any antibiotic, we’re aware of the potential for resistance. That is why we’ve already taken steps to establish a resistance surveillance mechanism through laboratory networks,” said Dr Asiedu.
For decades, azithromycin has been recommended by WHO to treat trachoma, another neglected tropical disease and a leading infectious cause of blindness worldwide.
Yaws and azithromycin
In 2012, researchers in Papua New Guinea discovered that a single dose of oral azithromycin was as effective as an injection of benzathine benzylpenicillin – the standard treatment against yaws for more than 60 years – in treating yaws. Similar findings from field trials in Ghana were published in 2017.
The effectiveness of azithromycin led WHO to revise its eradication strategy. Use of an oral route to cure yaws overcomes the operational and logistic constraints of the standard injection of benzathine benzylpenicillin.
Large-scale interventions also provide an opportunity to accelerate the treatment of entire affected communities/or individuals living in areas at risk and to improve the prospects for eradicating the disease as outlined in WHO’s roadmap on neglected tropical diseases.
Since 2012, WHO has advocated the need for donated azithromycin. The announcement by the Brazilian pharmaceutical company EMS at the Global Partners Meeting (April 2017) to donate azithromycin finally brings the much needed support to WHO in its global drive to eradicate yaws.
Yaws is a chronic bacterial infection caused by infection with Treponema pallidum subsp. pertenue, an organism resembling that which causes venereal syphilis. The disease is found primarily in deprived communities in tropical and forested areas of Africa, Asia, Latin America and the Pacific. Poor socioeconomic conditions facilitate its spread.
Humans are the main reservoir of the infection and children are the worst affected. Yaws clinically presents as lesions of the skin, bone and cartilage. Without treatment, it can lead to gross deformities and disabilities. Yaws forms part of a group of infections caused by treponemes that include endemic syphilis (bejel) and pinta.
In November 2012, the International Task Force for Disease Eradication at its 20th meeting in Atlanta, USA, endorsed WHO’s renewed efforts to eradicate yaws.