Neglected tropical diseases

Indonesia mobilizes resources to defeat yaws

19 May 2017 | Geneva

The World Health Organization (WHO) is recommending the expanded use of rapid serological tests in order to accelerate renewed efforts to interrupt transmission of yaws in Indonesia by 2020.

Ministry officials attending demonstration of a rapid diagnostic test in Timor Tengah Selatan District
Ministry officials attending demonstration of a rapid diagnostic test in Timor Tengah Selatan District - © Sub-Directorate of Leprosy and Yaws; MoH, Indonesia

Of the 514 districts in Indonesia, 74 report yaws cases and are considered endemic for the disease; the remainder are considered “non-endemic”. In 2015, the country set up a comprehensive programme to target the treatment of all endemic communities, aimed at interrupting transmission by 2020.

Strong political commitment has ensured adequate funding for the programme and the procurement by the Indonesian Ministry of Health of azithromycin - an oral antibiotic that can cure yaws infection.

“Interruption of transmission can be fast-tracked through practical point-of-care serological tests that can be performed by trained health workers in the field using a finger-prick blood sample,” said Dr Kingsley Asiedu, Medical Officer in charge of WHO’s yaws eradication programme. “This can facilitate immediate, precise treatment as the results can be read and interpreted within 20 minutes.”

Indonesia has a combined yaws and leprosy programme which functions under the Sub-Directorate of Leprosy and Yaws. This allows for the use of common resources to detect and manage both diseases at national, provincial and district levels.

“We have trained personnel at provincial and district levels, with technical guidelines and information, education and communication materials as well as surveillance forms to facilitate the expansion of yaws elimination,” said Dr Rita Djupuri, Manager of the Sub-Directorate of Leprosy and Yaws. “With clear milestones set, we are confident we can interrupt transmission by 2020.”

Recently, a WHO team visited several areas of Indonesia to assess eradication efforts and review implementation of the national elimination plan. Its recommendations include enhancing awareness of the disease to enable its recognition; implementing country-wide surveillance including in non-endemic areas; instituting a national verification mechanism; establishing a national reference laboratory to provide technical support; and monitoring of any resistance to azithromycin.

WHO is also recommending that documentation of processes and data at district, provincial and national levels should start now to support verification and certification in the future. After achieving interruption of transmission, a country needs to report zero yaws cases for 3 consecutive years and provide serological evidence to support the interruption of transmission in children aged 1–5 years in order to request yaws-free status by WHO.

“The widespread implementation of serological testing in children with suspected yaws lesions as recommended by the visiting experts will help improve the quality of the data reported, which have until now been based on clinical findings,” said Dr Ron Ballard, former Associate Director for Laboratory Science, United States Centers for Diseases Control and Prevention. “I am glad that the government is procuring large quantities of rapid tests for this purpose.”

Indonesia and East Timor are the only two remaining yaws-endemic countries in WHO’s South-East Asia Region.

In 2016, WHO certified India free of yaws.

WHO’s new eradication strategy

Until recently, the standard treatment for yaws was a single injection of benzathine benzylpenicillin. In 2012, the discovery that a single dose oral azithromycin could cure yaws has made large-scale treatment of affected populations more practical by obviating the cumbersome logistics and need for injections administered by trained health-care workers.

Based on this discovery, WHO developed a new strategy – The Morges Strategy – which provides two simplified treatment policies:

  • Total community treatment (TCT): treatment of an entire endemic community, irrespective of the number of active clinical cases.
  • Total targeted treatment (TTT): treatment of all active clinical cases and their contacts (household, school and playmates).

Collaboration with other disease programmes such as those for Buruli ulcer, cutaneous leishmaniasis and leprosy, as well as sexually transmitted infections, will be essential to advancing the eradication of yaws.

Besides Indonesia, yaws is known to be endemic in 12 other countries.

To achieve global interruption of transmission, a sustainable supply of azithromycin is critical. While countries like Indonesia are procuring the medicines to expand mass treatment, other countries will need donated azithromycin to implement WHO’s eradication strategy.

In April 2017 at the WHO Global Partners Meeting on neglected tropical diseases, the Brazilian pharmaceutical company EMS pledged to donate azithromycin to support the eradication effort.

The disease

Yaws is a poverty-related chronic skin disease that mainly affects children below 15 years of age (with a peak between 6 and 10 years). It is caused by infection with the bacterium Treponema pallidum subspecies pertenue and is transmitted by skin contact.

Yaws mainly affects the skin, but can also involve the bone and cartilage. The organism that causes yaws is closely related to that which causes syphilis. Early detection and treatment can avoid gross disfigurement and disability, which occur in about 10% of cases.

Yaws occurs in overcrowded communities, with limited access to basic amenities such as safe water and sanitation, as well as health care.