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, and anyone can get it. The mites don't care if you're clean, dirty, rich, or poor. All they want is to live on or in the skin of a human being, and any human being will do.

Scabies mites (so tiny they need a microscope to be seen) usually spread through skin-to-skin contact (especially among family members). Mites also can live for about 2 to 3 days in clothing, bedding, or dust, making it possible for scabies to spread among 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. Scabies also can be sexually transmitted.

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 (poop) 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 already has 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. Make sure to also trim your fingernails. Scrape off any debris or dirt from your fingertips, and put medicine on the fingertips as well. After applying the cream, 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 also will need to be treated for scabies.

Since scabies is highly contagious and can cause re-infestations, the other members of your household also should 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 itching, antihistamines. Sometimes itching can last for a few weeks even if a person no longer has scabies. If you still have a lot of itching after the infection has cleared, your doctor may prescribe a steroid skin cream like hydrocortisone. A steroid cream should be used only 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 finished.

Can I Avoid Getting Scabies?

Direct physical contact is the most common way to get scabies. It's also possible to get scabies from infected linens and clothing since scabies can live for 2 to 3 days away from human skin. So while 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. Wash clothing, sheets, and towels in hot water and dry on a hot setting. Put stuffed animals and other items that cannot be washed in a sealed plastic bag for at least 3 days. Vacuum each room in the house, then throw away the vacuum cleaner bag.