Scabies

Scabies is a skin infestation caused by the scabies mite. It often causes intense itchiness.

What is going on in the body?

The scabies mite, or Sarcoptes scabies, is specific to humans and spread by skin-to-skin contact. The mites live just below the skin's surface in an infected person. Generally, with the first episode of scabies, itching and skin lesions begin 1 to 1 1/2 months after infection. With reinfestation, symptoms often begin immediately. Scabies symptoms may continue for weeks or months prior to diagnosis and can continue for years if left untreated.

What are the causes and risks of the condition?

Scabies is caused when a person picks up the mites on his or her skin. Children under the age of 2 years are at high risk for scabies, as are their mothers. Soldiers, nursing home patients, and prison inmates in crowded conditions can also contract scabies readily.

What are the signs and symptoms of the condition?

Symptoms of scabies include the following:

How is the condition diagnosed?

A healthcare provider can generally diagnose scabies with a medical history and physical examination. In some cases, the provider may do a simple test to check for the mites or their eggs. A drop of mineral oil is placed on the skin lesion, and the surface of the lesion is scraped with a scalpel. The scraping is checked under a microscope to see if mites or eggs are present.

What can be done to prevent the condition?

Since scabies is spread by skin-to-skin contact, avoiding direct contact with infected people who have not been treated is the only prevention.

What are the long-term effects of the condition?

There are no long-term effects after a scabies infestation has been effectively treated.

What are the risks to others?

Scabies is contagious and can be passed from one person to another through direct contact.

What are the treatments for the condition?

Scabies is treated by applying permethrin cream or lindane lotion to the skin. Other medications include crotamiton and sulfur ointments. Antihistamines, such as diphenhydramine, may be used to relieve itching.

What are the side effects of the treatments?

Infants and children with a prior history of seizures have been known to have a seizure when lindane is used. Some individuals may have an allergic reaction to the lotions and creams used to treat scabies. Diphenhydramine can cause drowsiness or dry mouth.

What happens after treatment for the condition?

In general, symptoms of scabies are quickly relieved. Sometimes the skin irritation can continue. Occasionally, an individual may develop a secondary bacterial infection or skin inflammation that requires treatment. Any new or worsening symptoms should be reported to the healthcare provider.

People who have been in close contact with the infected person, such as family members, baby-sitters, or sexual partners, should also be treated for scabies.

How is the condition monitored?

Any signs of infection, or other new or worsening symptoms, should be reported to the healthcare provider.

Author:Lynn West, MD
Date Written:
Editor:Ballenberg, Sally, BS
Edit Date:02/28/01
Reviewer:Eileen McLaughlin, RN, BSN
Date Reviewed:07/27/01