• Tue. Apr 16th, 2024

Yaws, the second disease in the world to be eradicated?

ByElena Perez

Jan 28, 2017

Dr. Oriol Mitja is a young Spanish doctor who, after graduating from the Barcelona Institute of Global Heath and the London School of Hygiene and Tropical Medicine and following some breakthrough research on the diagnosis and treatment of yaws, set himself the goal of eradicating this disease in his lifetime. If successful, this would be the second disease to ever be whipped out of our planet. The Student had the chance to discuss the topic with him and find out more about this ambitious and exciting project.

Q: First of all, could you tell us a bit more about this disease? What is yaws, what are its symptoms, its prevalence and the population most at risk of becoming infected by it?

A: Yaws is an infectious disease of the skin that can be transmitted by direct or indirect contact (not sexual) and can even affect cartilage and cause deformities in the bones or face. People affected by it are mainly children up to 15 years old that live in tropical and poor areas of developing countries, principally in countries of the West Pacific, South America and Africa. Regarding its symptoms, it generally appears under the shape of yellowish lesions and raised or small cutaneous ulcers, mainly on the legs. Currently, it affects more than 100 000 children under 15 every year, although it is latent in an even bigger share of the population which is able to transmit it.

Q: Can you tell us a bit more about the single dose azithromycin treatment you are using? Had it been used before to treat yaws and is there any alternative to it for people who might be intolerant to this antibiotic?

A: Azithromycin is an antibiotic that countries from the first world use to treat conditions such as otitis or bronchitis, to give two examples. Our research showed that with a single dose of 500mg given to smaller children and a slightly higher dose for adults this antibiotic can eliminate yaws is only a few weeks and that the effects can be visible within few days. There are very few cases of intolerance but both for these cases and in cases where we find resistance, we can administer an injection of penicillin which was successfully used in the first eradication campaign carried out in the ’50s.

Q: Yaws has also been referred to as ‘the forgotten disease’. It was indeed among the first diseases targeted by WHO and UNICEF for eradication in 1950 but after reducing its incidence by 95%, the control campaign was suddenly halted in the late ’70s. How did this happen and how can we ensure this second attempt is more successful?

A: Yaws resurfaced because no monitoring of the population was done and, by not eliminating the disease 100% since it turned out impossible to reach the most remote sites to treat the whole population with penicillin injections, the door was left open for reinfection. We have learnt the lesson and now, in addition to knowing that we need to completely eradicate the disease, we know that we need to establish a lot of months of monitoring, including after administration of the last tablet.

Q: As opposed to unrealistic scientific targets our policy makers often set -regarding climate change for instance- this is actually a very feasible objective. What makes yaws such a realistic target for eradication? 

A: It is possible to eradicate this disease. It is possible because we have the treatment and this one is cheap. In addition, the disease is well localized. The only thing going against us, besides not having all the funds required, is that the last cases are in very remote areas where it will be difficult and expensive to deliver the treatment and establish posterior monitoring. The strategy developed by the WHO contemplates eradication of yaws by 2020.

Q: How close are we currently from reaching the target of eradication and how much longer do you think it will take? What are the remaining efforts and challenges to achieve that goal? In an interview, you said it was actually an affordable effort that would cost the equivalent of a football team. Why has it been so difficult to find the resources for it?

A: As I was mentioning in the previous question, WHO targeted eradication by 2020. In 2017 we will carry out actions of mass treatment in various African countries and in other provinces of Papua, which are currently the main hubs. After that, we will have to organize campaigns in more targeted areas until reaching definitive eradication. It is true that the cost is relatively small, keeping in mind what it means to eradicate a disease, which is something that has only been achieved once in history. But we need to remember that yaws is classified as a so-called ‘neglected disease’ and this classification, it did not earn it on a whim. Yaws affects very remote areas of the third world and very poor people, which is why it is has become almost invisible; these are areas with very little to no communication at all and that doesn’t help either.


[Translated from Spanish.]

Image: Tropenmuseum

Leave a Reply

Your email address will not be published. Required fields are marked *