Scabies

Scabies is a contagious skin condition caused by tiny mites which burrow into the skin. The main symptom of scabies is intense itching that is worse at night. It also causes a skin rash on areas where mites have burrowed.

Scabies is a contagious skin condition caused by tiny mites which burrow into the skin.

The main symptom of scabies is intense itching that is worse at night. It also causes a skin rash on areas where the mites have burrowed.

Read more about the symptoms of scabies.

How is scabies spread?

Scabies can be spread through:

  • long periods of skin-to-skin contact with an infected person
  • sexual contact with an infected person 

Scabies can also be passed by sharing clothing, towels and bedding with someone who is infected. However, this is less likely to cause an infection than skin-to-skin contact.

It can take up to eight weeks for the symptoms of scabies to appear after initial infection. This is known as the incubation period.

Read more about the causes of scabies.

In the UK, most scabies outbreaks occur during the winter. This may be a result of people spending more time indoors and in closer proximity to each other at this time of year.

Scabies mites

Scabies mites are called Sarciotes scabiei. They feed using their mouths and front legs to dig into the outer layer of the skin (the epidermis), ingesting tissue and fluids as they burrow.

As the mites feed within the skin layer, they lengthen their burrows horizontally by about 0.5mm a day. Females lay two to three eggs a day inside the burrow. After three to four days, the larvae (baby mites) hatch from the eggs and travel to the surface of the skin where they lie in shallow pockets before maturing into adult mites.

Scabies like warm places on the skin, such as skin folds, between the fingers, under fingernails or around the buttock or breast creases. They can also hide under watch straps, bracelets, or rings. 

Read more about the life cycle of the scabies mite.

Treating scabies

You should visit your GP if you think you have scabies. It is not usually a serious condition but does need to be treated.

The two most widely used treatments for scabies are permethrin cream and malathion lotion (brand name Derbac M). Both medications contain insecticides that kill the scabies mite.

Permethrin cream is usually recommended as the first treatment. Malathion lotion is used if permethrin cream proves ineffective.

If your partner has been diagnosed with genital scabies, to avoid re-infection you should visit your nearest sexual health clinic so you can be checked and, if necessary, treated.

You should avoid having sex and other forms of close bodily contact until both you and your partner have completed the full course of treatment.

Read more about diagnosing scabies and treating scabies.

Complications of scabies

Scabies can sometimes lead to a secondary skin infection if the skin becomes irritated and inflamed through excessive itching.

A rare but more severe form of scabies can develop in cases where there are a lot of mites in the skin. This is called crusted scabies and can affect older people and those with a lowered immune system (the body’s natural defence against infection and illness).

Read more about complications of scabies.

The main symptoms of scabies are intense itching and a rash in areas of the body where mites have burrowed.

The main symptoms of scabies are intense itching and a rash in areas of the body where mites have burrowed.

The itching is often worse at night when skin is warmer. It may take four to six weeks before itching starts because this is how long it takes for the body to react to mite droppings.

If you have had a previous scabies infection, the symptoms will start within one to two days. This is because your immune system will have learnt to respond to a scabies infection.

The rash

The scabies rash is made up of tiny red insect bites or spots. If you scratch the rash, you may also develop crusty sores.

Burrow marks can be found anywhere on the body but in adults they often appear in the following areas:

  • the folds of skin between fingers and toes
  • the wrists
  • the elbows
  • around the nipples (in women)
  • around the genital area (in men) 

The rash can also sometimes occur in the following areas:

  • the underarm area
  • around the waist
  • the inside of the elbow
  • the lower buttocks
  • the lower legs
  • the soles of the feet
  • the knees
  • the shoulder blades
  • the female genital area
  • the groin
  • around the ankles

Elderly people, young children and those with a low immune system (immunocompromised) may also develop a rash on their head and neck.

In infants and young children, burrow marks tend to appear in different places on their body, including on the:

  • face
  • head
  • neck
  • scalp
  • palms of the hands
  • soles of the feet

Scabies mites leave small red blotches and silver coloured lines on the skin. These marks are caused by the mites burrowing into the skin.

In infants with scabies, blisters and pustules (small blisters that contain pus) may develop on the soles of the feet and palms of the hands.

Scabies is a skin condition caused by the parasite Sarcoptes scabiei. The intense itching associated with scabies is thought to be caused by the immune system reacting to the mites and their saliva, eggs and faeces (poo).

Scabies is a skin condition caused by the parasite Sarcoptes scabiei.

The intense itching associated with scabies is thought to be caused by the immune system reacting to the mites and their saliva, eggs and faeces (poo).

The scabies mite life cycle

A scabies infestation starts when a female mite burrows into your skin.

Male mites move between different burrow sites looking to mate. After mating, the male mite dies and the female begins to lay eggs which hatch around three to four days later.

After hatching, the young mites move to the surface of the skin where they mature into adults after 10-15 days. Male mites stay on the surface of the skin, while female mites burrow back into the skin to create a new burrow. The life cycle is then repeated.

Without effective treatment, the scabies mite life cycle can continue indefinitely. Scabies mites are resistant to soap and hot water and cannot be scrubbed out of the skin.

How scabies is spread

Scabies mites cannot fly or jump, so they can only move from one human body to another if two people have direct and prolonged physical contact. For example, scabies mites can be transmitted by:

  • holding hands with an infected person for a prolonged period of time
  • having sex with an infected person 
  • sharing clothing, towels and bedding with an infected person (although this is rare)

It is unlikely that scabies will be transmitted through brief physical contact, such as shaking hands or hugging.

Scabies mites can survive outside the human body for between 24 and 36 hours, which makes it possible to become infected by coming into contact with contaminated clothes, towels or bed linen. However, it is rare to get the condition in this way.

Scabies infestations can spread quickly because people are usually unaware they have the condition until two to three weeks after the initial infection. There is an increased risk of catching scabies in confined environments, such as schools and nursing homes, where people are in close proximity to one another.

Risk groups

People often think that scabies is caused by unhealthy living conditions and poor personal hygiene. However, there is no evidence to suggest this. Anyone can get scabies, although certain groups are at increased risk because they are in close contact with lots of other people. These include:

  • children – due to outbreaks of scabies that can occur at schools and nurseries
  • young mothers – from close contact with affected children
  • elderly people – who live in nursing homes
  • sexually active people

Your GP will usually be able to diagnose scabies from the appearance of your skin and by looking for burrow marks made by the Sarcoptes scabiei mite.

Your GP will usually be able to diagnose scabies from the appearance of your skin and by looking for burrow marks made by the Sarcoptes scabiei mite.

However, as scabies is spread very easily, it is often possible to make a confident diagnosis if more than one family member has the same symptoms.

Ink test

The burrows of scabies mites can be identified by using an ink test. Ink is rubbed around an area of itchy skin before being wiped off with an alcohol pad. If scabies burrows are present, some of the ink will remain and will have tracked into the burrows, showing up as a dark line.

To confirm the diagnosis, a skin sample may be gently scraped from the affected area so it can be examined under a microscope for evidence of scabies mites, their eggs and faeces (poo).

Ruling out other skin conditions

Your GP will also want to rule out other skin conditions that may be causing your symptoms, such as:

  • eczema – a long-term skin condition that causes skin to become red, dry, cracked and itchy
  • impetigo – a highly contagious bacterial infection of the surface layers of the skin

Check up

Visit your GP if you think you have scabies. If you think you have genital scabies or your partner has been diagnosed with it, visit your nearest sexual health clinic where you will be examined and, if necessary, treated.

If you decide to treat yourself, you will need to have a full sexual health check to make sure you do not have any sexually transmitted infections (STIs).

To prevent re-infection, it is important that all members of your household are treated, as well as any sexual partners you have had over the last six weeks (in the case of genital scabies). If you have had genital scabies in the past, anyone you have had sex with in the previous 48 hours will need to be treated.

If you are embarrassed about contacting previous sexual partners, your GP surgery or local sexual health clinic may be able to inform them they have been exposed to scabies on your behalf, without disclosing your identity.

See your GP immediately if you contract scabies and have not had a previous infection. If you delay treatment, you risk passing scabies on to someone else.

See your GP immediately if you contract scabies and have not had a previous infection. If you delay treatment, you risk passing scabies on to someone else.

As other, more serious skin conditions can sometimes cause similar symptoms to scabies, your GP will need to rule these out.

If your partner has been diagnosed with scabies, you should visit your nearest sexual health clinic to be checked and, if necessary, treated.

To reduce the chances reinfection, avoid having sex and other forms of prolonged close bodily contact, such as holding hands, until both you and your partner have completed the full course of treatment.

Lotions and creams

The two most widely used treatments for scabies are special lotions or creams. Your doctor, pharmacist or nurse can advice you on which treatment to use.

Applying the cream or lotion

To prevent re-infection, all members of your household and any close contacts, including recent sexual partners (see diagnosing scabies for further details) should be treated at the same time as you, even if they do not have any symptoms.

You should apply the lotion to cool, dry skin and not after a hot bath. If you apply it when the body is hot, it will quickly be absorbed into the skin and will not remain on the area where the scabies burrows are present. You should also:

  • read the patient leaflet that comes with the product for details about where to apply the cream or lotion; some products need to be applied to the whole body, including the scalp and face, whereas others must only be applied from the neck down
  • pay particular attention to the areas that are difficult to reach, such as the back, the soles of the feet, between fingers and toes, under fingernails and the genitals
  • ensure that you apply it to areas where the scabies mites often burrow, such as the wrists, elbows, armpits, under the breasts and around the nipples in women
  • use a cotton bud or old toothbrush to apply the treatment under fingernails and toenails (afterwards, put the cotton bud or toothbrush in a bag and throw it away)
  • leave the treatment on the skin from 8-24 hours (depending on the preparation used) before washing it off thoroughly; follow the manufacturers guidance regarding how long to leave on the cream or lotion
  • immediately re-apply the cream or lotion to any areas of skin that are washed during the period of application
  • wash bed linen, nightwear and towels after the first application (see below)
  • repeat the treatment procedure seven days after the first application to ensure it is successful; the second application will ensure any mites hatched from existing eggs are killed

You should contact your GP if the itching does not improve after two weeks of treatment and you notice new burrows on your skin. They may recommend the treatment is repeated or prescribe a different lotion for you to use.

Also speak to your GP or pharmacist if you experience any persistent side effects.

Infection control

On the day you first apply the cream or lotion you should wash all bed linen, nightwear and towels at a temperature above 50C (122F).

If you are unable to wash certain items, place them in a plastic bag for at least 72 hours. After this time, the scabies mites will have died.

In cases of crusted scabies, you should clean the floors in your house and thoroughly vacuum your carpets and furniture (armchairs and sofa).

If you have been diagnosed with scabies, avoid close and prolonged physical contact with others until you have applied the cream or lotion. You should also avoid close contact with other household members until their treatment has been completed.

Children and adults can return to school or work after the first treatment has been completed.

Itchiness

Your GP should also be able to prescribe creams, such as a mild steroid cream, to help reduce itchiness. Calamine lotion, available without a prescription at pharmacies, may also help relieve itchy skin.

Oral antihistamines can also be used to help control itching and enable you to get a better night’s sleep. They can also be bought at your local pharmacy. However, oral antihistamines can cause drowsiness, so avoid driving or operating heavy machinery if you are affected in this way. Check with your GP or pharmacist if you are unsure.

You may continue to experience itchiness for a couple of weeks after your treatment has been completed. This is because your immune system will still be reacting to the presence of dead mites and their droppings. Visit your GP if you are still experiencing itchiness for longer than six weeks after your treatment has been completed.

A secondary infection and crusted scabies are two possible complications of scabies.

A secondary infection and crusted scabies are two possible complications of scabies.

Secondary infection

If you scratch the skin that is itching due to scabies, you may break the skins surface. This will make you more vulnerable to a bacterial skin infection, such as impetigoAntibiotics may be recommended to control a secondary infection.

Scabies has been known to make some pre-existing skin conditions, such as eczema, worse. However, other skin conditions should settle down after the scabies infection has been successfully treated.

Crusted scabies

Crusted scabies (also sometimes known as Norwegian scabies) is a more severe form of scabies where thousands or even millions of scabies mites are present.

Crusted scabies can start as normal scabies before developing into the more severe form following a skin reaction. The condition affects all parts of the body, including your head, neck, nails and scalp. However, unlike normal scabies, the rash associated with crusted scabies does not itch.

In crusted scabies, the increase in the number of mites causes the appearances of thick, warty crusts on the skin. The condition is often mistaken for psoriasis (a skin condition that causes red, flaky, crusty patches of skin covered with silvery scales).

Crusted scabies affects people with a weakened immune system (the body’s natural defence against illness and infection). This includes:

  • the very young
  • people with brain disorders (neurological disorders, such as Parkinson’s disease)
  • people with Down’s syndrome 
  • pregnant women
  • elderly people
  • people with a condition that affects their immune system, such as HIV or AIDs
  • people who are taking steroids to treat other medical conditions
  • people who are having chemotherapy treatment

Research has found that a healthy immune system appears to interrupt the reproductive cycle of the scabies mite. For example, most people with scabies will only have 5-15 mites on their body at any one time.

However, if your immune system is weakened, the number of scabies mites can increase significantly. People with crusted scabies can have thousands or millions of scabies mites in their body at any one time.

Due to the high number of scabies mites, crusted scabies is highly contagious. Even minimal physical contact with a person with crusted scabies, or with their bed linen or clothes, can lead to infection. However, contact with someone with crusted mites will only lead to the normal type of scabies in people with a healthy immune system.

Crusted scabies can be treated using insecticide creams or a medicine called ivermectin, which is taken by swallowing a tablet. Ivermectin kills the mites by stopping their nervous system from working.

See what your doctor sees, find out what is happening with your Scabies treatment and what the next steps might be.

The Map of Medicine is used by doctors throughout the NHS to determine the best treatment options for their patients. NHS Choices offers everyone in England exclusive and free access to this cutting-edge internet resource, which lets you see exactly what your doctor sees.

The information in the Map has been approved by the UKs leading clinical experts, is based on the best available clinical evidence, and is continually updated. To take advantage of this unique resource go to:

Map of Medicine: scabies