Scabies (mate māngeongeo riha) is a very itchy skin rash. It is caused by a reaction to a tiny mite that burrows under your skin.
Scabies is easily spread between people through close skin-to-skin contact and won't go away without treatment.
On this page, you can find the following information:
- What causes scabies?
- How do you get scabies?
- How do you know if you have scabies?
- Why is it important to treat scabies?
- How is scabies treated?
- I have used scabies treatment – why am I still itchy?
Key points about scabies
- Scabies is spread through skin-to-skin contact with a person who has scabies, or through shared bedding or clothing.
- You need to treat scabies with a lotion or cream called permethrin. It won’t go away on its own.
- Everyone who lives in the same household as the infested person needs to be treated at the same time.
- Wash all clothing and bedding in hot water after treatment.
- The itch may continue for a few weeks even though the mite is gone.
- See your doctor if itchiness continues for longer than 6 weeks.
What causes scabies?
Scabies is caused by tiny mites that burrow along just under the surface of your skin, laying eggs as they go. Scabies mites are part of the arthropod family and are close cousins to spiders and ticks.
Scabies mites are so tiny you can't see them. Scabies is a reaction to the mites, mite poo (faeces) and mite eggs. Small lumps grow on your skin and your skin gets very itchy, especially at night. The redness and small lumps look like a rash on your skin.
How do you get scabies?
Anyone can get scabies. It is more common when you have lots of people in close contact. Examples of close contacts are adults and children who live with you, and sexual partners. Outbreaks can occur in houses with overcrowding or rest homes. It isn't common for school children to pass scabies to each other. It is more common to get it in winter because the mite survives longer in the cold. Washing with soap will not prevent or cure it.
Scabies is usually spread by direct skin-to-skin contact with a person who has scabies. Contact generally needs to be prolonged – you are unlikely to get scabies from a quick handshake or hug.
Scabies is spread easily to household members and sexual partners. Scabies can also be spread by sharing clothing, towels or bedding used by a person with scabies.
Animals can also get scabies mites (called mange in animals) but they are a different kind that doesn't live on humans. This type of mite can cause itching in humans but it doesn't reproduce and so it will die on its own. If you think your pet might have mange then please take it to a veterinarian.
How do you know if you have scabies?
One of the first symptoms of scabies is a very itchy rash. This is usually worse when you are warm, such as when you are in bed or after a shower.
Symptoms generally start 3–6 weeks after infestation with the scabies mite. However, if you’ve had scabies before, the rash can start after only 1–3 days.
- The scabies rash generally looks like lots of small red bumps. They are harder to see on dark skin, but you should be able to feel them.
- The rash can appear anywhere on your body.
- The most common places for the rash are:
- between your fingers
- on the underside of your wrists
- on the outer surface of your elbows and knees
- around your waist
- on your bottom or genitals (private parts)
- in your armpits.
- The rash doesn't usually appear on your head (exceptions include very young children, older adults or people with a weakened immune system).
- Other conditions can cause a similar rash, so it can easily be confused with other skin conditions such as dermatitis or hives.
Not all people who have the scabies mite have itching. You can spread scabies, even if you do not have symptoms, until you are successfully treated and the mites and eggs are killed. Talk to your doctor, a nurse or a pharmacist if you think you might have scabies.
Scabies is diagnosed by symptoms rather than any special tests.
Image: DermNet NZ
See more images of scabies at DermNet NZ.
Why is it important to treat scabies?
Scabies won't go away without treatment and it is easily spread to close contacts. Scratching a lot can make skin conditions such as eczema or psoriasis worse. Scratching can also lead to skin infections such as impetigo or cellulitis.
See your doctor again if the sores or rash get redder, warm, start swelling or have pus, or if you get a fever (high temperature). This could mean you have a skin infection that needs treating with an antibiotic or other medicine.
How is scabies treated?
Scabies is usually treated with a cream or lotion called permethrin which kills the scabies mite. You can buy this from your pharmacy or get it on prescription from your doctor. You need enough cream/lotion to treat everyone in your household, even if they don't have any symptoms. One 30 gram tube is generally enough for an average sized adult and children will need less.
A second application of permethrin treatment is needed 7 days later to treat any newly hatched larvae. You or your child can go back to work or school 24 hours after the first treatment. Read more about permethrin and how to apply it.
|Permethrin may not be suitable for everyone – you may need a different treatment|
See your doctor for advice before treatment if you:
Although permethrin can be bought from a pharmacy without a prescription, it's important to talk to your healthcare provider if:
On the morning after everyone in your household has been treated
- Wash all clothing, sheets, towels, pillowcases and stuffed toys anyone has used in the past week in hot water (50°C).
- If you have a tumble drier, dry all items on the hottest tumble dryer setting for at least 10 minutes. Otherwise you can iron them with a hot iron.
- The scabies mite isn't small enough to go through the weave of sheets, so you don't need to wash mattresses or pillows.
- If clothes or linen cannot be washed:
- put then in a sealed bag for 4 days at room temperature until the mites die, or
- put them in a bag, spray them with fly/mite spray and seal for 2 hours, or
- seal in a plastic bag and freeze them overnight.
- Vacuum carpeted floors and upholstered furniture.
- Spray fly spray over furniture and beds where sheets haven't been used and avoid human contact for 4 days.
If you don’t do these things, the mites will re-infest your whānau.
I have used scabies treatment – why am I still itchy?
Although the treatment kills the scabies mites quickly, the itching can carry on for a few weeks. The intense itch generally improves after 1 week of treatment. However, it can take 4–6 weeks for the itch and rash to clear completely, even though all mites have been killed.
Treat itchy patches with antihistamines, moisturisers or mild steroid creams. Crotamiton cream (Eurax®, Itch-Soothe®) is used to reduce itch. Calamine lotion may also help relieve itching, but it won't kill the mites.
See your doctor if your skin is still itchy 6 weeks after treatment.
Other reasons you may still be itchy
- The diagnosis may be incorrect. Scabies can be confused with a number of other skin conditions, particularly dermatitis and hives. Coeliac disease is another cause of an ongoing itchy rash.
- You may need to repeat the scabies treatment. Ask your pharmacist or doctor for advice. Don't repeat treatment more than twice without medical advice. Overuse of insecticides such as permethrin can irritate your skin.
- Not timing your treatment with that of close contacts. It's important that all close contacts are treated at the same time, otherwise you will be re-infested and it won't work.
- Resistance to treatment. Scabies occasionally appears to be resistant to the prescribed scabies treatment. You may need to try a different treatment. If the itching continues, talk to your doctor.
Scabies DermNet, NZ
Scabies summary, symptoms, treatment, prevention Ministry of Health, NZ
Getting rid of scabies HealthInfo, NZ
Scabies frequently asked questions (FAQs) CDC, US
- Scabies – diagnosis and management BPAC, NZ, 2022
- Scabies NHS, UK, 2020
- Getting rid of scabies HealthInfo, NZ, 2022
|Jeremy Steinberg is a GP with special interests in musculoskeletal medicine, evidence-based medicine and use of ultrasound. He's been reviewing topics for Health Navigator since 2017 and in his spare time loves programming. You can see some of the tools he's developed on his website.