Scabies:
Information for adults

Scabies is an itchy skin condition caused by a tiny parasite (mite) called Sarcoptes scabiei that can live and multiply (infest) on skin. They are passed between people by prolonged skin-to-skin contact. Scabies is extremely contagious and spreads rapidly in crowded conditions such as hospitals, nursing homes, child care facilities, and other situations where people spend extended periods of time in close contact with each other.

The itchy rash of scabies develops when a pregnant female mite burrows into the outer surface (superficial) skin and lays eggs. The human immune system is highly sensitive to the presence of the mite and produces a massive allergic response, which causes intense itching. Although a typical infection includes only 10–20 mites, people are so sensitive to the mite that there are often hundreds of itchy skin lesions that result. Without treatment, the condition will not usually improve.