Scabies

Scabies is diagnosed and treated by the Dermatology Division of Premier Medical Group.

What is scabies?

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Scabies is a condition that occurs when the skin is infested by Sarcoptes scabiei var. hominis, known colloquially as the human itch mite. These microscopic mites burrow into the outermost layer of the epidermis, living and laying eggs indefinitely. This causes an itchy, red rash on the skin. Medications can kill the mites and their eggs, but the mite is very contagious. Recognizing their bites and distinctive rash is essential for preventing further spread.

Scabies is an infestation rather than an infection, and there are approximately 130 million cases of the infestation at any given time. Scabies is not a sexually transmitted disease, but sexual acts are a common vehicle for spreading the infestation. Scabies can also spread rapidly in crowded conditions, where close body contact is frequent. This includes nursing homes, extended-care facilities, and summer camps. The infestation can be spread through infested clothing and bedding.

What causes scabies?

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Scabies are caused by body mites, known scientifically as Sarcoptes scabiei. These mites are transferred between people through skin contact, such as during sex, in crowded areas, and in places where many people live together, like nursing homes. However, the mite can also live in fabric for up to three days. These mites are exceedingly contagious and can spread quickly through close physical contact. As a result, doctors will often recommend scabies treatment for entire families or contact groups to prevent further spread, even if a rash has not appeared.

What are the symptoms of scabies?

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Scabies symptoms include severe itching that intensifies at night. This is typically accompanied by thin, irregular blisters and bumps on the skin. The rash can consist of tiny bites, hives, and bumps under the outermost layer of the epidermis, which appear as pimple-like protrusions. After initial exposure to the mites, it can take up to six weeks for these symptoms to appear. They typically develop faster in people who have had scabies before.

Scabies rashes most often appear in folds of skin, but almost any part of the body can develop the itch. The rash is most often found in the following places:

  • Between the fingers
  • Around the waist
  • Along the insides of wrists
  • In the armpits
  • On the soles of the feet
  • On the inner elbows
  • Around male sex organs
  • Around the breasts
  • On knees
  • On the buttocks

Those who may be immunocompromised, or extremely old or young, may see scabies on the head, face, neck, or hands. While you may feel the urge to itch a scabies rash, especially at night, continuous scratching can create sores which may then become infected. This is why prompt scabies treatment is important not just to kill the mites and eggs, but to limit the places where the infestation can get a new foothold.

How is scabies diagnosed?

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While a scabies diagnosis can be made based on the appearance and distribution of the rash, it should be confirmed by a mite or egg identification whenever possible. This is done by carefully removing a mite from the end of its burrow using a needle.

It is important to remember that fewer than 10-15 live mites may be present on an infested person. Dr. George T. Nahass, board-certified dermatologist and dermatopathologist, says that if you cannot find a mite but are still experiencing symptoms, it can be a good idea to get a skin scrape. “The doctor can then examine the scraping under a microscope, looking for eggs and fecal matter,” he says.

Whether you can extract a mite or require a skin scrape, it is essential to consult a doctor for a formal diagnosis. While an individual may be able to self-diagnose a scabies infestation, only a doctor can prescribe the necessary treatment. If you remove a mite on your own, do your best to preserve it. Showing the mite to a doctor can help expedite the diagnosis and treatment.

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The products used to treat scabies are called scabicides, as they kill the mites and eggs. These products are only available with a doctor’s prescription, and, as you might with crabs or head lice, it is important to follow all instructions very carefully. The scabicide lotion or cream should be applied to all areas of the body, especially between fingers and toes. Itching may continue for several weeks after the treatment, but if itching is still present after a month (or if rashes continue to appear), additional treatment and preventative steps may be necessary.

If you have a confirmed case of scabies, a doctor will prescribe treatment to all members of your household, those with whom you have had sexual contact, and anybody you are in close physical contact with during the day. All people should be treated at the same time to prevent re-infestation. Additionally, bedding, clothing, and towels should be decontaminated by washing in hot water and drying in a hot dryer, dry-cleaning, or by sealing in a plastic bag for more than 72 hours. This will kill any mites lingering on fabric.

There are several over-the-counter products advertised for scabies, but these preparations will only ease itching. Only prescribed scabicide will eliminate scabies.

When to see a doctor for scabies?

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It is important to see a doctor if you have signs and symptoms that indicate scabies. Prompt treatment is the best thing you can do for this extremely contagious condition. Don’t let personal embarrassment keep you from getting relief. As the American Academy of Dermatology points out, “People who are very clean and neat can get scabies. People of all ages, races, and income levels get scabies.”

Several skin conditions, including eczema and dermatitis, are also associated with itching and small bumps on the skin. You can also take a look at our main resource page if you believe a sexually transmitted disease may be the cause of your symptoms. Your doctor can determine the exact cause and provide appropriate treatment.