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Scabies: The Seven-Year-Itch

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  • Blurred lines

    Blurred lines

    The phrase “the seven-year itch” was made popular by the classic movie starring Marilyn Monroe. But the real seven-year itch — scabies — is anything but romantic! It’s sometimes called that because the incidence of scabies may wax and wane in seven-year cycles.

    Scabies is caused by parasites that feed and breed under human skin. Scabies is extremely itchy and causes unsightly grey lines on the skin along with red bumps. It can be difficult to treat. Scabies mites are transmitted by skin-to-skin contact with an infected person, or by extended contact with the clothing, bedding, or towels of an infected person.

  • What is scabies?

    What is scabies?

    Scabies is a skin infection caused by tiny mites. Scabies mites burrow under the upper layer of human skin, feeding on blood and laying eggs. People of any class or race can get scabies. They are most common where living conditions are crowded.

    Norwegian, or crusted, scabies is a severe form occurring in people with weakened immune systems. Scabies mites don’t live on animals. They crawl and are unable to jump or fly. Scabies mites cannot live away from a human host for more than three days, but they can survive for one to two months with a host.

  • Coming of age

    Coming of age

    Scabies eggs are laid under the skin and hatch into larvae after about four days. In another four days, the mites are mature and ready to lay the next generation of eggs. This cycle continues until halted by medical treatment. Scabies can live and breed on your skin for several weeks before your immune system has an allergic reaction and symptoms appear.

  • What to look for

    What to look for

    Scabies mites have a round body and eight legs. You might not be able to see the mites without a microscope, but you can see the bumps and the raised tracks where they lay their eggs.

  • What is that rash?

    What is that rash?

    Scabies looks similar to rashes caused by:

    • dermatitis
    • syphilis
    • poison ivy
    • other parasites, such as fleas

    The scabies rash looks like blisters or pimples: pink, raised bumps with a clear top filled with fluid. Sometimes they appear in a row. The skin may also have red and scaly patches. The strongest indicator of scabies is bumps plus the characteristic skin tracks. Scabies mites attack the entire body, but they particularly like the skin around the hands and feet, where the itch can be maddening.

  • Getting rid of scabies

    Getting rid of scabies

    The nickname “seven-year itch” is well-earned —scabies can be difficult to eliminate. Treatment is usually a topical medication that is prescribed by a doctor.

    Itching may continue for weeks, even if the first application of medicine works. Be sure to remain on the lookout for new tracks or bumps. These signs may be indications that a second treatment is necessary. Anyone exposed to scabies should be treated.

  • How bad is it?

    How bad is it?

    The mere thought of playing host to a family of scabies mites is frightening in and of itself. It should be noted, however, that scabies mites don’t transmit diseases. That said, extensive scratching could cause secondary infection, including impetigo. In rare instances, Norwegian scabies can develop. Usually this more severe version only develops as a result of a weakened immune system or when a scabies infestation goes untreated for months or years.

  • Get treatment

    Get treatment

    If you are experiencing itchy blisters and a pattern of tracks on your skin, especially on your hands or feet, you may have scabies. It is important to see a doctor immediately. You’ll also want to ensure anyone you’ve been physically near is treated. Don’t wait seven years!