Scabies << SKAY beez >> is a contagious skin disease that causes intense itching. In adults and older children, scabies may affect any part of the body from the neck down. It most frequently involves the skin between the fingers, under the arms, and on the wrists, elbows, breasts, genitals, and lower back. Babies may be infected over their entire body, including the head. The disease is most common in babies and elderly people who live in poor countries.
Scabies is caused by the itch mite, a spiderlike animal known scientifically as Sarcoptes scabiei. This mite can barely be seen with the unaided eye. The female digs a burrow under the skin and lays eggs there. The eggs hatch three to five days later. The young mites mature into adults in five days to two weeks. They mate on the skin surface, and the females then dig their burrows. Most infected people have 10 to 15 mites in their skin.
Scabies is spread through skin contact. An infected person does not show symptoms at first. The mites can spread from person to person before symptoms appear. After four to six weeks, the presence of the mites and their excrement (waste) within the skin causes an allergic reaction. The allergic reaction produces an itchy rash.
People with weak immune systems may develop a severe form of scabies called crusted scabies, also known as Norwegian scabies. Patients with crusted scabies are highly contagious. They often do not itch, but their skin may become dry and scaly. A patient with crusted scabies may have as many as 2 million mites in their skin.
Doctors treat scabies with creams or lotions that kill the mites. Antiparasitic medication taken by mouth, such as the drug ivermectin, also kills the mites. To contain the spread of the disease, doctors treat all members of the patient’s household.
