Norwegian, or crusted, scabies is caused by touching the skin or contaminated items such as bedding and furniture, according to the Centers for Disease Control and Prevention (CDC). It is often found in people with compromised immune systems and is very contagious.
Patients with Norwegian scabies have thick crusts on their skin that contain a large quantity of scabies mites and their eggs, the CDC states. This form of scabies often does not produce the symptoms associated with other varieties, such as a rash and intense itching. Norwegian scabies is more contagious because of the larger number of mites living on the skin.
Patients that are elderly, disabled or who have medical conditions that compromise their immune system are the most likely to contract Norwegian scabies, the CDC reports. It is important for patients with this form of scabies to receive immediate treatment to prevent an outbreak.
If a person has not had scabies before, symptoms may not occur for four to six weeks, the CDC says. Patients who have had the condition previously can have symptoms as soon as one to four days after exposure.
Scabies is a skin infection in which a mite burrows under the top layer of skin and lays eggs, the CDC explains. It is common in crowded conditions where people have frequent skin-to-skin contact, such as nursing homes, prisons and day care centers.