These infections are spread by any close contact with the skin of an infected person—usually between children living in conditions of poor hygiene.
Bejel causes mouth sores and destructive lumps in bone.
Yaws causes skin sores and disfiguring growths on the legs and around the nose and mouth.
Pinta causes itchy, thickened, discolored patches on the skin.
Doctors diagnose these infections when people have typical symptoms and have spent time in areas where the infections are common.
One injection of penicillin kills the bacteria.
(See also Overview of Bacteria.)
Disorders that are caused by Treponema, such as bejel, yaws, and pinta, are known as treponematoses. Syphilis is another treponematosis caused by the closely related bacteria called Treponema pallidum. However, syphilis and bejel, yaws, and pinta are spread in different ways. Syphilis is spread by sexual contact, whereas bejel, yaws, and pinta are spread by any close contact (sexual or not) with the skin of an infected person—chiefly between children living in conditions of poor hygiene. Bejel also may be spread by mouth-to-mouth contact or when eating utensils are shared. Also unlike syphilis, bejel, yaws, and pinta are not spread through contact with contaminated blood or from mother to fetus during pregnancy.
Bejel occurs mainly in the hot, dry regions of the eastern Mediterranean and Saharan West Africa.
Yaws occurs in hot, humid countries that are very near the equator in Africa, Latin America, Asia, and the Pacific Islands.
Pinta is common among the natives of Mexico, Central America, and South America. Pinta is not very contagious.
Bejel, yaws, and pinta rarely occur in the United States, except among immigrants from areas of the world where these diseases are common.
Yaws and pinta, like syphilis, begin with skin symptoms. Bejel begins with mouth sores. These symptoms subside, and after a period with few or no symptoms, new symptoms develop.
Bejel typically begins in childhood. It affects the mucous membranes of the mouth, then the skin and bones. The initial mouth sore may not be noticed. Moist patches then develop in the mouth. They resolve over a period of months to years. During this time, people have few or no symptoms. Then, sores may develop on the trunk and limbs.
Lumps develop in long bones, mainly leg bones, and in the tissues around the mouth, nose, and roof of the mouth (palate). These lumps destroy tissue, causing bones to be deformed and disfiguring the face.
Yaws also affects the skin and bones. Several weeks after exposure to Treponema, yaws begins as a slightly raised sore at the site of infection, usually on a leg. The sore heals, but later, soft nodules (granulomas) form, then break open on the face, arms, legs, and buttocks. The granulomas heal slowly and may return. The skin on the palms of the hands and on the soles of the feet may thicken and break open to form painful sores. The sores on the feet make walking difficult and force people to walk on the sides of their feet, giving rise to the nickname crab yaws.
Later, areas of the shinbones may be destroyed, and many other destructive, disfiguring growths, especially around the nose, mouth, and palate, may develop.
Pinta affects only the skin. It begins as flat, itchy, reddened areas on the hands, feet, legs, arms, face, or neck. These areas enlarge and thicken. After several months, thick, flat patches develop all over the body. They tend to develop where bones are close to skin, for example, on the elbow.
Later, the patches lose their color or turn gray-blue. Without treatment, these patches usually do not go away.
Doctors make the diagnosis of bejel, yaws, and pinta when typical symptoms appear in people who live in or have visited an area where such infections are common. Sometimes doctors examine a sample from the skin sores under a microscope.
Because the bacteria that cause these infections and the bacteria that cause syphilis are so similar, doctors sometimes do blood tests for syphilis. People who have one of these infections test positive for syphilis.
A single injection of long-acting penicillin (benzathine penicillin) kills the bacteria. Then, the skin can heal. However, some scarring may remain, particularly if a lot of tissue has been destroyed. People who are allergic to penicillin may be given a single dose of azithromycin by mouth. For people who are not pregnant or who are 8 years or older, doxycycline given by mouth for 14 days is an alternative.
Public health officials try to identify and treat infected people and their close contacts.