What is scabies?
Human scabies is caused by an infestation of the skin by the human itch mite (Sarcoptes scabiei var. hominis). The microscopic scabies mite burrows into the upper layer of the skin where it lives and lays its eggs.
Scabies is found worldwide and affects people of all races and social classes. Scabies can spread rapidly under crowded conditions where close body and skin contact is frequent. Institutions such as nursing homes, extended-care facilities and prisons are often sites of scabies outbreaks. Child care facilities also are a common site of scabies infestations.
How do you get scabies?
Scabies usually is spread by direct, prolonged, skin-to-skin contact with a person who has scabies. Contact generally must be prolonged; a quick handshake or hug will not usually spread scabies.
It can also be spread indirectly by sharing articles such as clothing, towels or bedding that have been used by person who has scabies. Such indirect spread can occur much more easily when an infected person has crusted scabies.
Pets do not cause human scabies infections.
Signs and symptoms
If you have never had scabies before, symptoms may take as long as 4 to 6 weeks to begin. It is important to remember that a person with an infestation can spread scabies during this time, even if they do not have symptoms yet.
If you have had scabies before, symptoms usually appear much sooner (1 to 4 days).
The most common signs and symptoms of scabies are an intense itching (pruritus), especially at night, and a pimple-like (papular) itchy rash.
The itching and rash may affect much of your body or be limited to common sites. Some of these common sites include:
- webbing between the fingers
The rash also can include tiny blisters (vesicles) and scales.
Tiny burrows sometimes are seen on the skin; these are caused by the female scabies mite tunneling just beneath the surface of the skin.
These burrows appear as tiny raised and crooked (serpiginous) greyish-white or skin-colored lines on the skin surface.
As mites are often few in number (only 10-15 mites per person), these burrows may be difficult to find. They are found most often in the webbing between the fingers, in the skin folds on the wrist, elbow, or knee, and on the penis, breast, or shoulder blades.
The head, face, neck, palms, and soles of the feet are often involved in infants and very young children with scabies, but usually not adults and older children.
Persons with crusted scabies may not show the usual signs and symptoms of scabies such as the characteristic rash or itching (pruritus).
How do I know I have scabies?
If you or your child has a raised rash that itches intensely (pruritus), especially at night, you should see your doctor. Scratching the rash can cause skin sores, which can sometimes become infected by bacteria.
Treatment of scabies
If you are diagnosed with scabies you should be treated, along with your regular sex partners and any other contacts with who you have had prolonged skin-to-skin contact.
If you are diagnosed, treatment is also recommended for all members of your household. Everyone within the household should be treated at the same time to prevent reinfestation.
Retreatment may be necessary if itching continues more than 2 to 4 weeks after treatment or if new burrows or rash continue to appear.
A number of topical creams and lotions are available to treat scabies.
Applying the treatment
Follow the advice below to effectively treat scabies:
- Creams and lotions are better absorbed after a shower and towel drying.
- Apply a thin layer of the cream or lotion to your whole body surface, from the chin down. A pastry brush may make it easier to apply.
- If possible, ask someone else to apply it for you. This will make sure your whole body surface is covered.
- Avoid your eyes, nose and mouth.
- Pay particular attention to the areas between your fingers, under your nails, the soles of your feet and between your buttocks.
- Do not wash your hands after treatment.
- Leave treatment on the body for 12 to 24 hours and then wash thoroughly. People often choose to apply the cream in the evening and leave it on overnight.
- Re-apply the cream to any area that has been washed within 12 to 24 hours.
- The treatment may need to be repeated in a week’s time to kill recently hatched mites.
- If the pimples or spots become infected, antibiotics may be necessary.
While you have scabies
If you or person within your household has scabies, make sure you wash personal items and clothing (including bedding or towels) that you or the person with the infestation may have used in the last 2 days.
Items should be machine-washed in hot water and dried thoroughly. Items can also be dry-cleaned. Otherwise you can also remove such items from any skin contact for 72 hours.
Failure to wash all items used by an infected person can result in re-infestation.
How can scabies be prevented?
- Practice good hygiene measures, for example do not share clothes unless they have been washed.
- Change and wash bed linen regularly.
- Observe the skin of close contacts for signs of raised bumpy rash on the legs and hands – if you see a rash, avoid personal contact.
- Scabies is a skin infestation caused by mites.
- Scabies leads to red, itching bumps or blisters on the skin.
- If you develop scabies, your sexual partners and all members of your household will also require treatment.
- Treatment is effective if the instructions are followed carefully.
This publication is provided for education and information purposes only. It is not a substitute for professional medical care. Information about a therapy, service, product or treatment does not imply endorsement and is not intended to replace advice from your healthcare professional. Readers should note that over time currency and completeness of the information may change. All users should seek advice from a qualified healthcare professional for a diagnosis and answers to their medical questions.