Sarcoptes scabiei or the itch mite is a parasitic mite that burrows into skin and causes scabies. The mite is found in all parts of the world. Humans are not the only mammals that can become infected. Other mammals, such as wild and domesticated dogs and cats (in which it is one cause of mange) as well as ungulates, wild boars, bovids, wombats, koalas, and great apes are affected.

The Italian biologists Giovanni Cosimo Bonomo and Diacinto Cestoni showed in the 17th century that scabies is caused by Sarcoptes scabiei; this discovery of the itch mite in 1687 marked scabies as the first disease of humans with a known microscopic causative agent. The disease produces intense, itchy skin rashes when the impregnated female tunnels into the stratum corneum of the skin and deposits eggs in the burrow. The larvae, which hatch in three to 10 days, move about on the skin, moult into a nymphal stage, and then mature into adult mites. The adult mites live three to four weeks in the host's skin.