Yaws is a chronic skin infection characterized by papillomas (noncancerous lumps) and ulcers. It is caused by the bacterium Treponema pallidum subspecies pertenue, which belongs to the same group of bacteria that causes venereal syphilis.
Yaws primarily affects children aged under 15 years who live in poor communities in warm, humid and tropical forested areas of Africa, Asia, Latin America and the Pacific islands. The majority of affected populations live rural areas, far from health services. Poverty, low socio-economic conditions and poor personal hygiene facilitate the spread of yaws.
Although there are over 80 000 cases of yaws each year, experts believe the disease can be controlled and ultimately eradicated for several reasons. First, it only occurs in humans, not animals, making control much easier. It is also easy to treat with readily available drugs and has already been eliminated in some countries, including India. The remaining pockets of yaws infection, although usually in remote places, means further spread is less likely with proper surveillance and control measures.
There is currently no vaccine for yaws. Health education and improved personal hygiene are the most important tactics for prevention.
There are two stages of yaws infection. The early stage is when the patient is infectious and can spread the disease to others. In this stage, a papule (a noncancerous, outward-growing lump) develops at the site of infection. This papule is full of the organisms and may persist for 3–6 months followed by natural healing. Without treatment, this is followed by disseminated skin lesions over the body. Bone pain and bone lesions may also occur.
Yaws is a chronic skin infection characterized by papillomas (noncancerous lumps) and ulcers. It is caused by the bacterium Treponema pallidum subspecies pertenue, which belongs to the same group of bacteria that causes venereal syphilis.