Scabies is a highly contagious skin disease caused by tiny mites that burrow into the skin. Scabies is usually spread through direct contact or sexual contact, especially on active young couple. In some cases, scabies are passed through sharing of personal things such as clothing and towels.
Crusted scabies, a rare but more severe form of scabies, can develop in older people and those with a lowered immunity. In this case, large number of mites is in the skin.