Scabies:
Teen information

Scabies is a very itchy, contagious rash caused by tiny mites that infest the skin. The mite (called Sarcoptes scabiei) lives on the skin and tunnels under the skin in straight or wavy fashion, causing the characteristic rash: general redness and itchiness with some raised pink straight or wavy lines. The rash is usually most obvious in the spaces between the fingers and in body creases such as the armpits, groin, breasts, and elbows. The itchiness can be intense and is often worse at night. The mites are passed by skin-to-skin contact and also by sharing intimate objects such as towels, sheets, and mattresses. The skin-to-skin contact needs to be prolonged, so a hug or a handshake will likely not transmit the mites. Even though mites can infect the groin, scabies is not considered a sexually transmitted disease. 

The first time a person is exposed to mites, it may take weeks for the itchy rash to develop; on subsequent exposure(s) to mites, the itchy rash will likely develop within days.