Scabies

Scabies

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What Is Scabies?

Scabies (pronounced: skay-beez) is a common skin infestation of tiny mites called Sarcoptes scabiei. The mites burrow into the top layer of human skin to lay their eggs, causing small itchy bumps and blisters.

Someone with scabies might notice a bumpy red rash. Occasionally, raised wavy lines where the mites have burrowed may appear, especially on the inner part of the wrist or between the fingers or toes.

How Do People Get Scabies?

Scabies is contagious from person to person. Scabies mites (so tiny they need a microscope to be seen)are usually transmitted by prolonged skin-to-skin contact (especially among family members) and also by sexual partners. Mites can live for about 2 to 3 days in clothing, bedding, or dust, making it possible to catch scabies from people who share the same infected bed, linens, or towels.

Scabies spreads more easily in crowded conditions — like within a household, childcare centers, and college dorms — where people tend to be in close contact with each other.

It may take up to 4 to 6 weeks after infection for symptoms to appear in a person who's never had scabies before. In people who have had scabies previously, symptoms may appear in just a few days.

What Are the Signs and Symptoms?

The most common symptom of scabies is severe itching, which may be worse at night or after a hot bath. A scabies infection begins as small, itchy bumps, blisters, or pus-filled bumps that break when you scratch them. Itchy skin may become thick, scaly, scabbed, and crisscrossed with scratch marks. The itching is due to a reaction of your body to the mite and/or its feces and eggs.

The areas of the body most commonly affected by scabies are the hands and feet (especially the webs of skin between the fingers and toes), the inner part of the wrists, and the folds under the arms. It may also affect other areas of the body, particularly the elbows and the areas around the breasts, genitals, navel, and buttocks.

If a person with scabies scratches the itchy areas of skin, it increases the chance that the injured skin will also be infected by bacteria. Impetigo, a bacterial skin infection, may occur in skin that is already affected by scabies.

How Do Doctors Treat Scabies?

Scabies infections need to be treated by a doctor. Call your doctor or dermatologist any time you have a skin itch that will not go away, especially if the itch is worse at night and seems to center around the wrists or the webbed part of the fingers.

If your doctor suspects you have scabies, he or she may scrape a small part of the affected skin and examine the scrapings under a microscope for signs of scabies mites.

Doctors treat scabies by prescribing a medicated cream or lotion. The cream will need to be applied all over the body (except the face, eyes, and mouth), and usually must remain on the skin for 8 to 12 hours before it can be washed off. After applying it, don't wash your hands — scabies mites love the area between the fingers! Most often, the treatment needs to be repeated in 1 week.

Because scabies can be sexually transmitted, sexually active teens with scabies should be examined for other sexually transmitted diseases (STDs), too. Any sexual partners will also need to be treated for scabies.

Since scabies is highly contagious and can cause re-infestations, the other members of your household should also be treated for scabies, even if they have no symptoms.

If you develop a bacterial skin infection such as impetigo in addition to the scabies infection, your doctor may prescribe antibiotics and, to treat the itching, antihistamines. The itching can, however, last for a few weeks even if you no longer have scabies.

If you still have a lot of itching after the infection has resolved, the doctor may prescribe a topical steroid cream like hydrocortisone. Such a steroid cream should only be used if recommended by your doctor because certain infections can become worse with its use. You can return to school or work the day after the treatment is complete.

Can I Avoid Getting Scabies?

Practicing good hygiene is the best way to prevent getting scabies. Take showers or baths daily; wash your hands frequently, especially before eating; and wear clean clothing.

Direct physical contact is the most common way to get scabies. But it's also possible to get it from infected linens and clothing since scabies can live for 2 to 3 days away from human skin. Though it can be tempting, try not to share clothing with friends.

If someone in your family is being treated for scabies, all other household members should be treated, too. Clothing, sheets, and towels should be washed and dried in hot water. Stuffed animals and other items that cannot be washed can be kept in a sealed plastic bag for minimum 3 days. Each room in the house should be vacuumed, and the vacuum cleaner bag should then be thrown away.

Reviewed by: Yamini Durani, MD
Date reviewed: May 2011

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Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.
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