Yaws eradication

28 February 2018

Yaws is a chronic infectious disease that is closely linked to poverty. It is eradicable as humans are the only hosts. A global campaign using benzathine penicillin injection reduced 95% of global cases in the late 1960s. However, abandonment of programmes and weak surveillance led to resurgence in many countries, prompting WHO to re-start control programmes in 2007.

The discovery in 2012 that a single, oral dose of the antibiotic azithromycin can completely cure yaws has added momentum to eradication. Today, only 14 countries are known to be endemic. In 2017, Philippines confirmed some cases. India is the first country officially declared free of yaws by WHO in 2016.

WHO/1957 (Indonesia)

Tackling a post-war public health problem 1948−1958

When WHO was established in 1948, yaws and other bacterial infections caused by treponemes such as endemic syphilis (bejel) and pinta were some of the pressing public health problems it had to tackle head-on. Over 50 million people, mainly children, were affected.

©WHO/Friedrich C. Tross, 1953 (Phillipines)

Yaws begins where the road ends

Historically, yaws is considered as an “end of the road disease” because people affected are mostly poor and live in difficult-to-access areas. Health workers faced serious difficulties in reaching affected populations.

©WHO/1953 (Phillipines)

Start of the eradication campaign in 1952

Between 1952 and 1964, WHO and UNICEF supported mass treatment campaigns in 46 countries. WHO provided technical support and UNICEF gave logistical assistance. An estimated 300 million people were screened and over 50 million treated, reducing the disease burden by 95%.

©WHO/C.J. Hackett, 1952 (Liberia)

The "magic bullet" that revolutionized treatment

The development of benzathine penicillin coincided with the birth of WHO in 1948. The second World Health Assembly (1949) adopted a resolution to control yaws. Affected populations were treated with a single injection of benzathine penicillin with a spectacular cure within 2-3 weeks. The populations and health workers described the medicine as a “magic bullet”.

OMS/P. Almasy

Health education - key to community participation

Health education and disease awareness were central to the past eradication campaign. Engaging the community was crucial to ensuring high treatment coverage and in effectively reducing transmission.

©MSF/Lam Duc Hien, 2012 (Congo)

Yaws is cured with a single oral dose of an inexpensive antibiotic called azithromycin.

In 2012, a significant breakthrough occurred when it was discovered that a single-dose oral azithromycin as an alternative to penicillin injection. This finding led to renewed interest in yaws eradication through large-scale treatment of affected populations.

©MSF/Lam Duc Hien, 2012 (Congo)

The “magic tablet” accelerates the path to eradication

The efficacy of oral azithromycin in mass treatment has been tested through pilot programmes in 5 countries since 2012. All tests have demonstrated excellent results with complete cure achieved within 2-3 weeks of a patient taking the required dose of the antibiotic.

©WHO/NTD, 2015

The renewed eradication strategy

The oral treatment overcomes operational and logistic constraints of injectable benzathine penicillin. In 2012, WHO convened a meeting of experts to develop a new eradication strategy. Known as the Morges Strategy, the approach is radically different and focuses on active screening and large-scale treatment with oral azithromycin of entire populations at risk.

WHO certifies India as free of yaws

India is the only country so far in this millennium to have eliminated yaws through a sustained campaign using injectable penicillin. The last cases were reported in 2003. After 3 years of no new cases, India declared interruption of transmission (elimination). In 2015, a WHO International Verification Team confirmed India’s claim and in 2016 WHO declared India as the first country as free of yaws.

Global eradication is feasible by 2020

The availability of an oral antibiotic, new diagnostic tools, experience gained from pilot studies, and, India’s historic achievement all point to better prospects for eradication in the remaining 14 countries by 2020. The critical challenge is ensuring adequate provision of azithromycin to reach populations in need.