Yaws - Causes, Symptoms and Treatment .MF .

August 12, 2017 17:52 | Infectious Diseases

Yaws is one of the most neglected tropical diseases that affect the skin, bone and cartilage.The disease is caused by bacteria belonging to the same group of organisms that cause venereal syphilis;but yaws transmission occurs asexually.

yaws can be eliminated, as the only reservoir is humans.In a recent study it was shown that a single dose of the antibiotic azithromycin, taken orally, can completely cure yaws, which opens up prospects for large-scale remedial measures in relation to population, are affected by this disease.

Ecuador and India are among the two countries that were once the endemic, who reported on the termination of transmission of the disease in 2003.By 2014, 12 endemic countries need support for the implementation of the new WHO strategy to eliminate the disease.

Yaws is a group of chronic bacterial infections caused by treponemes, which are endemic syphilis (bezhel) and a pint, and that is usually known as endemic treponemal.Yaws is the most common of these infections.

disease is usually spread among the poor in Africa, Asia, Latin America and the Pacific Rim, with a warm climate and important in areas of the rainforest.


yaws The disease is also known as framboesia (German or Dutch) and called pian (French) and affects the skin, bone and cartilage.The disease is caused by a microorganism T. pallidum subspecies pertenue.This body belongs to the same group of bacteria that cause venereal syphilis.

transmission mechanism. Yaws is transmitted directly through non-sexual contact (person-to-person) with a biological fluid from the lesion of an infected person.Most of the lesions located in the extremities.At the site of the original lesion yaws is a large amount of bacteria.Contact with the liquid of this lesion, especially if it occurs in children who play and have minor scratches, resulting in transmission of the infection.

incubation period of 9-90 days (average 21 days).

About 75% of infected - children under 15 years of age (peak incidence of the disease is seen in children aged 6 to 10 years).Individuals of both sexes are affected equally.

spread of yaws promotes overcrowding and poor socio-economic conditions.Without treatment, the infection can lead to chronic disfigurement and disability.

campaign to eliminate the disease in the 1952-1964 biennium.conducted in 46 countries.Since 1990 the official statements by the WHO against yaws has been discontinued due to the closure by the elimination of yaws programs in many countries.Only in some countries, yaws was part of the action program in the field of public health.

study of documents remaining from the 1950s, shows that at least 90 countries in the tropical belt is located 20 degrees north and 20 degrees south of the equator, were among the endemic yaws.However, only 12 are considered to be currently endemic yaws, while in respect of the two countries - Ecuador and India, claiming that stopped transmission of the disease in 2003, should be checked.In addition, WHO also plans to check the status on the yaws in 76 countries, which were previously endemic.

Reporting by yaws is not mandatory, so the available data, published in the latest edition of the Weekly Epidemiological Record, are only an indication of the global spread of the disease.

Symptoms yaws

There are two basic stages of yaws: early stage (infectious) and late stage (non-infectious).

In the early stages of yaws on the site of entry of bacteria develop initial papilloma (rounded dense swelling of skin with no visible fluid discharge).This papilloma filled with bacteria and may persist for 3-6 months and completed a natural recovery.Further, bone pain and bone damage can also occur at an early stage.Next may appear polymorphous skin rash, increased and painful lymph nodes.

Late manifestations of yaws appear 5 years after the initial infection and characterized by disfigurement and nose bones, thickening of the palms and soles of the feet and the appearance of cracks in them (frambeziyny hyperkeratosis).These complications in the feet leads to the fact that the patient becomes difficult to walk.The disease lasts for many years without causing death.

In the field, diagnosis is primarily based on the results of a clinical and epidemiological surveys.

Diagnostics yaws

To diagnose treponemal infections (eg, syphilis and yaws) are widely used serological tests.

However, rapid tests can not distinguish between active yaws and the treated infection.New, conducted at the place of treatment, double, non-treponemal and treponemal syphilis rapid tests offer hope for a quick confirmation of the active form of yaws in the field.Studies to evaluate the new test set are held in Ghana, Papua New Guinea, the Solomon Islands and Vanuatu.

analysis based on polymerase chain reaction (PCR).For the final confirmation of yaws can be used genomic analysis based on polymerase chain reaction (PCR).PCR method can also be used to detect resistance to azithromycin according to the results of analysis of smears taken from the affected areas of yaws.

Treatment of yaws

For the treatment of yaws can use two antibiotics.Azithromycin (single oral dose) of 30 mg per kilogram of body weight (up to 2 grams).Benzathine penicillin (one intramuscular dose) at the rate of 1.2 million units (for adults) and 600 000 units (for the children).

Complications Without treatment, about 10% of people suffering from yaws after 5 years develop disfiguring and disabling complications leading - straining limbs and nose.


yaws yaws vaccines do not exist.Preventive work is timely diagnosis and treatment.An important component of prevention is personal hygiene and the elimination of direct contact with the patient.When contact occurred once justified prophylactic bitsillina.

resumption of work on the elimination of the disease

«Road map of the WHO to combat neglected tropical diseases" and Resolution WHA 66.12 define 2020 as the year of the elimination of yaws in countries still remaining endemic.

yaws can be eliminated, because its people are the only reservoir.If all segments of the population at risk through large-scale programs to provide treatment with azithromycin in an oral form, the transmission of the disease is interrupted and the disease will be eliminated in this area.Offensive outburst, aimed at achieving this, is gaining momentum and WHO, together with partners, led by increased efforts to eliminate yaws.To ensure the smooth implementation of measures to achieve the 2020 targets is crucial to ensure azithromycin in sufficient quantities, the availability of rapid diagnostic tests and the necessary funding.

WHO Media Centre