Scabies

What is scabies? What causes a scabies infestation?

Scabies is an itchy, highly contagious skin disease caused by an infestation by the itch mite Sarcoptes scabiei. Mites are small eight-legged parasites (in contrast to insects, which have six legs). They are tiny, just 1/3 millimeter long, and burrow into the skin to produce intense itching, which tends to be worse at night. The mites that infest humans are female and are 0.3 mm-0.4 mm long; the males are about half this size. Scabies mites can be seen with a magnifying glass or microscope. The scabies mites crawl but are unable to fly or jump. They are immobile at temperatures below 20 C, although they may survive for prolonged periods at these temperatures.

Scabies infestation occurs worldwide and is very common. It has been estimated that worldwide, about 300 million cases occur each year. Human scabies has been reported for over 2,500 years. Scabies has been reported to occur in epidemics in nursing homes, hospitals, long-term care facilities, and other institutions. In the U.S., it is seen frequently in the homeless population but occurs episodically in other populations of all socioeconomic groups as well.

Reviewed on 6/1/2012