General informationScabies can occur in people of all ages and is highly contagious, spreading easily between family members and friends. Because it is spread by skin contact and the sharing of clothing and bedding, scabies is more likely to occur when many people live together in the same household. Sometimes it is spread through sexual contact, especially in young adults. Scabies is also common in nursing homes and long-term care facilities.
CausesScabies is caused by the scabies itch mite, which is less than half a millimetre across (or about the size of a pin head). The female mite burrows just beneath the skin surface producing a tunnel or track in which it lives and feeds and lays its eggs. Larvae hatch from the eggs and move to the skin surface where they are able to spread to other areas of your skin or to the skin of other people. The rash and itchy skin in areas where the mite has burrowed is the result of the body’s allergic reaction to the mites and their eggs and waste.
Signs and symptoms
General signs and symptoms of scabies include:
- Intensely itchy skin, with the itching being worse at night-time
- Burrows, which appear as thin, grey, irregular tracks on the skin (2-10mm long)
- Rash, appearing as small red blisters or bumps on the skin
- Lumps or nodules in the armpits and groin.
Scabies primarily occurs on the insides of the wrists, the skin between the fingers, elbows, upper surface of the feet, around the waist, and the buttocks and genitalia. Elderly people who are bed bound or have weakened immune systems, as well as infants and young children, can also develop scabies on the face, scalp, neck, palms of the hands, and soles of the feet.
A diagnosis of scabies can be made by your doctor with a physical examination, on the basis of the rash and thread-like burrows. Laboratory tests are not usually necessary.
Everyone living in the same house should be treated at the same time, even if they do not have itchy skin.
Scabies treatment involves the application of topical medications (creams and lotions) containing chemicals that kill the scabies mite and eggs.
The medication should be applied all over the body, from the neck down to the feet. It is preferable to apply the medication before bedtime so that it is left on for at least eight hours before being washed off in the morning. In more severe cases it may be necessary to repeat the treatment.
Commonly used topical medications include and insecticide called permethrin. An oral medication, ivermectin, may be prescribed for severe cases of scabies. These medications kill the mites quickly but it may take up to one month for the itching to go away. If your rash persists you should see your doctor. An antibiotic may be prescribed if a skin infection has developed.
Helpful home treatments include applying soothing lotions, such as calamine, and taking over-the-counter oral antihistamine drugs to relieve the itching and other allergic symptoms. Bathing in cool water or applying a cool wet washcloth to affected areas may also provide relief from the itching.
The following steps will help to prevent scabies from coming back or spreading to other people:
- Washing everyone’s clothes, sheets, pillowcases, towels, and facecloths in hot soapy water and drying them in a clothes dryer on high heat or sealing them in a plastic bag for 3-4 days (this kills the mites by removing them from their food source). Dry-cleaning is also effective in killing the mites
- Non-washable items can be placed in a sealed plastic bag and stored for at least one week
- All carpets, carpeted floors and upholstered furniture should be vacuumed and the vacuum's contents discarded.
Freephone 0800 611 116
Barry, M. (2017). Scabies (Web Page). Medscape Drugs and Diseases. New York, NY: WebMD LLC. https://emedicine.medscape.com/article/1109204-overview [Accessed 12/02/18]
Ministry of Health (2016). Scabies (Web Page). Wellington: New
Zealand Government Ministry of Health. https://www.health.govt.nz/your-health/conditions-and-treatments/diseases-and-illnesses/scabies [Accessed 12/02/18]
Monsel, G., Chosidow, O. Management of scabies. Skin Therapy Lett. 2012;17(3):1-4.
O’Toole, M.T. (Ed.) (2013). Scabies. Mosby’s Dictionary of Medicine, Nursing & Health Professions (9th ed.). St Louis, MI: Elsevier Mosby.
Reviewed: February 2018