Though scabies is extremely contagious, it usually requires prolonged skin-to-skin contact with a person who is already infested. Limited contact, such as a hug or handshake, will not normally spread the infection. However, scabies is easily spread to sexual partners and to other members of the household. Even if a person does not yet have symptoms, he or she can pass the infestation on to other people.
Less commonly, it may be spread by sharing towels, clothing, or bedding. Although the entire body may itch, the most common locations for the lesions of scabies include: The areas between the fingers finger webs Inner wrists, inner elbows, and armpits Breasts of females and genitalia of males Navel umbilicus Lower abdomen Buttocks Backs of knees Although in adults it is rare to see lesions on the face, scalp, and neck, these areas are commonly affected in children aged younger than 2 years.
The most obvious signs of scabies are pink-to-red bumps, which can look like pimples or bug bites, sometimes with scale or a scab on them. However, the tell-tale lesion of scabies is the burrow, which is small and often difficult to see. Typically, a burrow appears as a small, thread-like, scaly line 3—10 mm long , sometimes with a tiny black speck the burrowing mite at one end.
The adult mite is about 0. Scabies mites crawl; they do not jump or fly. People who are exposed to scabies may not develop itchy lesions for up to 6 weeks after becoming infested, as the immune system takes some time to develop an allergic response to the mites.
However, individuals who have had scabies before may develop the rash within several days of re-exposure. Scabies is intensely itchy, especially at night. Excessive scratching of the itchy lesions can create breaks in the skin, which may then become infected with bacteria.
The lesions are widespread, appearing over the scalp, face, elbows, knees, palms, and soles of the feet. Interestingly, these infestations may not be itchy, although the lesions may contain up to two million mites.
Scabies requires prescription medication in order to stop the infestation. Once you are under a doctor's care, there are steps you can take to prevent scabies from coming back: Mites cannot survive off the human body for more than 48—72 hours. Therefore, wash all clothing, bedding, and towels used by the infested person in the past 72 hours in hot water, and dry these items in a hot dryer.
Vacuum all carpets, rugs, and furniture, and discard the vacuum bags. Put anything that cannot be laundered into plastic bags for at least 72 hours. Pets do not need to be treated because the mite only lives on humans. If you've had scabies before, the itching usually begins within one to four days. When a person has not had scabies, the body needs time to develop a reaction to the mite.
It can take two to six weeks to develop symptoms. Itching, mainly at night: Itching is the most common symptom. The itch can be so intense that it keeps a person awake at night. Rash: Many people get the scabies rash. This rash causes little bumps that often form a line. The bumps can look like hives, tiny bites, knots under the skin, or pimples. Some people develop scaly patches that look like eczema.
Sores: Scratching the itchy rash can cause sores. An infection can develop in the sores. Thick crusts on the skin: Crusts form when a person develops a severe type of scabies called crusted scabies.
Another name for crusted scabies is Norwegian scabies. With so many mites burrowing in the skin, the rash and itch become severe. You'll find more information about crusted scabies below. The severe itch can lead to constant scratching. With non-stop scratching, an infection can develop.
Non-stop scratching can even lead to sepsis, a sometimes life-threatening condition that develops when the infection enters the blood. Scabies can develop anywhere on the skin. The mites, however, prefer to burrow in certain parts of the body. The most common places to have itching and a rash are:.
Hands: Mites like to burrow in the skin between the fingers and around the nails. Skin usually covered by clothing or jewelry: The buttocks, belt line, penis, and skin around the nipples are likely places for mites to burrow.
Vigorous scratching can break your skin and allow a secondary bacterial infection, such as impetigo, to occur. Impetigo is a superficial infection of the skin that's caused most often by staph staphylococci bacteria or occasionally by strep streptococci bacteria.
A more severe form of scabies, called crusted scabies, may affect certain high-risk groups, including:. Crusted scabies, also called Norwegian scabies, tends to make skin crusty and scaly, and affects large areas of the body.
It's very contagious and can be hard to treat. Normally, someone with scabies has about 10 to 15 mites. In contrast, someone with crusted scabies may be infested with millions of mites. To prevent re-infestation and to prevent the mites from spreading to other people, take these steps:.
Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission. This content does not have an English version. This content does not have an Arabic version. Overview Scabies Open pop-up dialog box Close.
Scabies Scabies is caused by tiny mites that burrow into your skin. Request an Appointment at Mayo Clinic. Share on: Facebook Twitter. Show references AskMayoExpert. Mayo Clinic; Goldstein BG, et al. Scabies: Epidemiology, clinical features, and diagnosis.
0コメント