|LETTER TO THE EDITOR
|Year : 2015 | Volume
| Issue : 3 | Page : 791-792
A road map to global eradication of yaws by 2020
Department of Community Medicine, Shri Sathya Sai Medical College and Research Institute, Kancheepuram District, Tamil Nadu, India
|Date of Submission||29-Aug-2014|
|Date of Acceptance||09-Sep-2014|
|Date of Web Publication||22-Oct-2015|
Department of Community Medicine, Shri Sathya Sai Medical College and Research Institute, Kancheepuram District, Tamil Nadu
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Annadurai K. A road map to global eradication of yaws by 2020. Menoufia Med J 2015;28:791-2
Yaws was the first disease identified by the WHO for eradication after World War II after the establishment of WHO. Yaws is caused by Treponema pallidum subsp. pertenue, which affects the skin, bones, and cartilage and is transmitted mainly through direct skin contact. It is one of the neglected tropical diseases as it is more prevalent among poor and socially excluded population. Early infectious stage and late noninfectious stage are the two clinical stages observed in yaws. In early stage, an initial papilloma will be developed at the site of entry of bacterium and filled with organisms, which will heal spontaneously after a period of 3-6 months. After 5 years of initial infection, late yaws will develop in about 10% of untreated patients and is characterized by disfigurement of the nose and bone and thickening and cracking of palms and soles, which will leave a patient with chronic disability. Rapid serological test is widely used to diagnose yaws, and PCR is utilized for confirmation and determination of antibiotic resistance ,.
In 1952, there were about 50 million reported cases of yaws and through mass penicillin campaigns by WHO and UNICEF, it was reduced to 2.5 million; however, because of lack of sustained effort, there was resurgence of cases in the 1970s . The first attempt 1950-60s campaign on eradication failed because of early shift of disease focus without proper surveillance, inadequate funding and drug supply, poor drug compliance for penicillin injection, lack of identification and treatment of contacts and subclinical cases, and insufficient community awareness that led to resurgence .
In 2012, WHO has set target as the year 2020 for yaws eradication and has adopted milestones such as nil reporting of yaws cases from 50% of endemic countries by 2015 and 100% of endemic countries to report zero cases by 2017 for interruption of transmission of yaws . Because of inadequate reporting and lack of notification and surveillance system, no accurate data on yaws were available. Between 1950 and 2013, about 90 countries have reported yaws . After India and Ecuador successfully interrupted transmission of yaws by 2003, it regained importance, and, in 2007, WHO meeting with endemic countries stressed on reassessment of yaws burden. In 2012, WHO consultation on eradication of yaws was held in Morges, Switzerland and proposed newer strategy called 'Morges strategy' for its eradication .
According to WHO, there were 12 yaws endemic countries in 2013, namely Benin, Cameroon, Central African Republic, Republic of the Congo, Côte d'Ivoire, Democratic Republic of the Congo, Ghana, Togo, Indonesia, Papua New Guinea, Solomon Islands, and Vanuatu, with estimated 21-42 million peoples living at risk of developing yaws. From 2008 to 2011, there were about 87 982 cases of yaws with 75% of them below 15 years of age group. Majority of the cases were reported from Papua New Guinea and Solomon Islands of western Pacific region and Ghana of African region .
From the pilot studies, it has been proved that mass single-dose oral azithromycin will interrupt the transmission of disease within 6 months. Morges strategy for eradication plans to cover at least 90% of population either through total community treatment or total targeted treatment in affected regions with single-dose azithromycin (30 mg/kg body weight with a maximum of 2 g). However, earlier strategy with single-dose injection penicillin targeted therapy only on those with visible infection  [Table 1].
Yaws cases are commonly reported in tropical region with heavy rainfall and are associated with poor economic condition, low standards of hygiene, overcrowding, and extensive vegetations, which result in injury to extremities and increase the chances of infection . Many studies have shown that human yaws is having possible nonhuman reservoirs such as baboons and gorillas, which needs further evaluation .
To fulfill the criteria for interruption of transmission of disease, the endemic countries should not report yaws cases for three consecutive years, and it should be supported by negative serological survey. For better implementation of the new strategy, it needs mapping of endemic foci, identification of at risk population, capacity building, surveillance and reporting of cases, case finding and treatment with single-dose azithromycin, health education of at risk population, adequate research, proper monitoring and evaluation, and above all local and international commitment toward eradication of yaws .
For monitoring of yaws, WHO has adopted the following indicators such as the number of new cases of yaws reported monthly from a community, percentage of coverage of treatment, and the serological prevalence of yaws in children aged 1-5 years, once there is nil cases reported . The current challenges are to monitor the development of drug resistance, accessibility and follow-up of the patients residing in remote areas, adequate surveillance mechanism, uninterrupted drug supply, and reviewing the current status of yaws in previous endemic countries .
To prevent resurgence and to reach the target of eradication by 2020, it needs sustained and adequate community action together with national and international political commitment to free the globe off yaws.
| Acknowledgements|| |
Conflicts of interest
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