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Can the Infectious Disease Yaws Be Eradicated?

Can the Infectious Disease, Yaws, be Eradicated SoonYaws is a relatively unknown disease in the developed world, but in poor tropical areas of Africa, Asia, Latin America and the Western Pacific, it is common and can lead to disfigurement and disability.

Yaws is the most common endemic treponematoses, a group of bacterial infections that also includes nonvenereal syphilis and pinta. All of these infections are transmitted through non-sexual contact with an infected person. They can cause skin lesions, bone pain, bone lesions, nose deformities and the thickening or cracking of a person’s hands and soles of the feet. The World Health Organization (WHO) estimates that 75% of infected people are under 15 years of age, with most cases seen in children aged 6 to 10. Gender is not a determining factor of infection.

Yaws is spread through skin-to-skin contact, usually after a small injury occurs, something common when children play. Yet, WHO states that “overcrowding, poor hygiene and socioeconomic conditions facilitate the spread of the yaws.”

The disease is not life-threatening, which is likely why it became a neglected disease in the scope of global disease work. But if left untreated, a person can become permanently disfigured and disabled. Such a diagnosis is bad for anyone infected with the disease, but since mostly children suffer from yaws, it becomes a life-long issue if not resolved quickly. When a child contracts yaws, their ability to go to school is jeopardized. If left untreated, absenteeism rises among children and their future employment, especially feeding their families through farming, is impacted.

It has long since been thought that yaws could be a disease that can have complete eradication since humans are the only carriers of the disease. Previously, initiatives to eradicate yaws were undertaken with almost complete success. But the mass effort was prematurely lifted and the disease returned, though not quite on the same scale as before.

Recently, the idea of complete eradication has come back up. The two most effective antibiotics to treat yaws are azithromycin and benzathine penicillin, both of which can be given with relative ease. Even though no vaccine is available for yaws, if early diagnosis is achieved, treatment with the antibiotics can occur and sanitation can be improved to help stop the spread of the disease. With the steps, the end of yaws is in sight.

There have already been cases of previously endemic countries achieving complete eradication, including India. The Yaws Eradication Programme (YEP) was launched in India in 1996 with the goal to have complete eradication in the country. In 1997, 735 cases of yaws were reported; in 2004, the country was considered to have achieved “Zero Case.” Because not all cases of yaws are reported, only time will tell if complete eradication can be sustained, but right now all signs are pointing to success.

With great things already happening in India and a plan in place to achieve more success globally, yaws should be eradicated from remaining endemic countries by 2020.

– Megan Ivy

Sources: PubMed.gov, WHO 1, WHO 2
Photo: Chacha

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Top 5 Neglected Tropical Diseases

dengue-fever
Neglected tropical diseases are poorly understood, lack appropriate control tools, receive smaller investments in research and development, and affect people living in remote rural areas with limited access to treatment. Innovative and Intensified Disease Management (IDN) focuses on overcoming these hurdles to control, and hopefully eradicate NTDs.

These are seven diseases that the World Health Organization classifies as neglected.

1. Buruli Ulcer
Buruli Ulcer is characterized by a swelling in the skin called a nodule, which eventually spreads to become large ulcers typically appearing on arms and legs. Infection is caused by a germ from the same family as leprosy and tuberculosis. Cases have been reported in over 30 countries, but primarily in poor rural communities. Progress is being made toward a vaccine able to treat Buruli Ulcer, but in the meantime the Bacille Calmette-Guérin (BCG) vaccine offers some protection.

2. Dengue
Dengue is a viral infection spread through mosquito bites. The infection causes severe flu-like symptoms, and can sometimes lead to a deadly condition called severe dengue. The disease thrives in urban poor areas in tropical and subtropical communities. Severe dengue has become a leading cause of death among children and adults in Asian and Latin American countries.

3. Leishmaniasis
Leishmaniasis is a disease that can be directly linked to poverty. It is associated with malnutrition, displacement, poor housing, weakened immune systems and lack of resources. The interaction of Visceral Leishmaniasis (VL) with HIV has devastating consequences; a simultaneous HIV infection increases the risk of developing active VL by up to 2320 times. 90% of all VL cases occur in Bangladesh, Brazil, India, Nepal and Sudan.

4. Leprosy
Leprosy is a chronic infectious disease that exists in extremely impoverished communities. It affects the skin, nerves, upper respiratory tract and eyes. Most countries have achieved elimination at the national level, and are intensifying their efforts at regional and district levels. It is estimated that up to two million people are visibly disabled due to leprosy. Education, early diagnosis and adequate medicinal interventions are key elements for eradicating the disease.

5. Rabies
Rabies is a vaccine-preventable disease transmitted from animals to humans by a virus present in the saliva of infected carriers. Bites or scratches from infected animals are the most common form of transmission to humans. The disease infects both domestic and wild animals. If left untreated, Rabies is almost always fatal.

6. Trachoma
Trachoma is caused by a microorganism which spreads through contact with eye discharge from an infected person. A single episode is not considered sight-threatening, but prolonged, repeated infection can lead to scarring inside the eyelid, which in turn causes scarring of the cornea. If left untreated, Trachoma leads to permanent blindness. Trachoma affects 21.4 million people, often striking women and children. Factors such as water shortage, poor hygiene conditions and crowded households have caused the infection to be extremely common in many of the poorest regions of the world.

7. Yaws
Yaws is a chronic bacterial infection that occurs mostly in poor communities in the humid tropical regions as a result of overcrowding, poor sanitation and other poverty-related issues. Skin-to-skin contact with an infected person leads to development of a single lesion; if left untreated, lesions will spread to the entire body. Nearly 75% of people affected are children under 15 years, and although rarely fatal, yaws can lead to chronic disfigurement and disability. Experts are confident that the disease can be controlled and possibly eradicated. India for example, has seen no new yaws cases since 2004.

– Dana Johnson

Source: WHO, WHO Resolution