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. Crusted scabies is a severe form of scabies that can occur in some persons who are immunocompromised have a weak immune system , elderly, disabled, or debilitated. It is also called Norwegian scabies. Persons with crusted scabies have thick crusts of skin that contain large numbers of scabies mites and eggs. Persons with crusted scabies are very contagious to other persons and can spread the infestation easily both by direct skin-to-skin contact and by contamination of items such as their clothing, bedding, and furniture.
Persons with crusted scabies may not show the usual signs and symptoms of scabies such as the characteristic rash or itching pruritus. Persons with crusted scabies should receive quick and aggressive medical treatment for their infestation to prevent outbreaks of scabies.
If a person has never had scabies before, symptoms may take weeks to develop. In a person who has had scabies before, symptoms usually appear much sooner days after exposure. The most common signs and symptoms of scabies are intense itching pruritus , especially at night, and a pimple-like papular itchy rash.
The itching and rash each may affect much of the body or be limited to common sites such as the wrist, elbow, armpit, webbing between the fingers, nipple, penis, waist, belt-line, and buttocks. The rash also can include tiny blisters vesicles and scales.
Scratching the rash can cause skin sores; sometimes these sores become infected by bacteria. 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 grayish-white or skin-colored lines on the skin surface.
Because mites are often few in number only 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 often are involved in infants and very young children, but usually not adults and older children. 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 usually will not spread scabies. Scabies is spread easily to sexual partners and household members. Scabies in adults frequently is sexually acquired. Scabies sometimes is spread indirectly by sharing articles such as clothing, towels, or bedding used by an infested person; however, such indirect spread can occur much more easily when the infested person has crusted scabies.
Diagnosis of a scabies infestation usually is made based on the customary appearance and distribution of the rash and the presence of burrows. Whenever possible, the diagnosis of scabies should be confirmed by identifying the mite, mite eggs, or mite fecal matter scybala.
This can be done by carefully removing a mite from the end of its burrow using the tip of a needle or by obtaining skin scraping to examine under a microscope for mites, eggs, or mite fecal matter. This is because many people don't visit their GP and treat the condition with non-prescription medicines. Visit your GP if you think you have scabies.
It's not usually a serious condition, but it does need to be treated. The 2 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. Malathion 0. If your partner has been diagnosed with genital scabies, to avoid reinfection you should visit your nearest sexual health clinic so you can be checked and, if necessary, treated.
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. Scabies can sometimes lead to a secondary skin infection if your skin becomes irritated and inflamed through excessive itching.
Crusted scabies is a rare but more severe form of scabies, where a large number of mites are in the skin. This can develop in older people and those with a lowered immunity. Read more about complications of scabies. The main symptoms of scabies are intense itching and a rash in areas of the body where the mites have burrowed.
The itching is often worse at night, when your skin is warmer. It may take 4 to 6 weeks before the itching starts because this is how long it takes for the body to react to mite droppings. Symptoms will start within 1 to 2 days if you've had a scabies infection in the past. This is because your immune system will have learned to respond to a scabies infection. The scabies rash consists of tiny red spots. Scratching the rash may cause crusty sores to develop. Burrow marks can be found anywhere on the body.
They're short 1cm or less , wavy, silver-coloured lines on the skin, with a black dot at one end that can be seen with a magnifying glass. The rash usually affects the whole body, apart from the head. The following areas can be particularly affected:. Elderly people, young children and those with a low immune system immunocompromised may also develop a rash on their head and neck. Men usually have 1 or more very itchy, lumpy, 3 to 10mm spots on the skin of the genitals on the penis and scrotum.
In infants and young children, burrow marks tend to appear in different places on their body, including on the:. 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.
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.
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 3 to 4 days later.
After hatching, the young mites move to the surface of the skin, where they mature into adults after 10 to 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 life cycle of the scabies mite can continue indefinitely. Scabies mites are resistant to soap and hot water and can't be scrubbed out of the skin. Scabies mites can't fly or jump, which means they can only move from one human body to another if 2 people have direct and prolonged physical contact.
It's 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 24 to 36 hours, making infection by coming into contact with contaminated clothes, towels or bed linen a possibility. However, it's rare for someone to be infected in this way.
Scabies infestations can spread quickly because people are usually unaware they have the condition until 2 to 3 weeks after the initial infection.
There's an increased risk of catching scabies in confined environments, such as schools and nursing homes, where people are in close proximity to one another. Your GP should be able to diagnose scabies from the appearance of your skin, and by looking for the burrow marks of the Sarcoptes scabiei mite. However, as scabies is spread very easily, it's often possible to make a confident diagnosis if more than one family member has the same symptoms.
Your GP will also want to rule out other skin conditions that may be causing your symptoms, such as eczema or impetigo a highly contagious bacterial skin infection.
These burrows may look like slightly raised and crooked skin-colored or gray-white lines. Learn how to identify scabies bites here. Scabies spreads through extended, skin-to-skin contact with someone who has scabies. In adults, the transmission of scabies frequently occurs through sexual contact. When a person has scabies, there are usually only 10—15 mites on their body at any given time, which makes spread through casual contact less likely. Therefore, a handshake or hug will not usually spread it.
Scabies can spread more easily in crowded, close quarters, such as child care centers, nursing homes, and prisons. A person can also get scabies indirectly by sharing towels, sheets, blankets, pillows, or clothes with someone who has the condition.
Pets and animals cannot spread scabies. Pets can get mange, which results from a different kind of mite and could make someone itch for a few days, but it is not the same as scabies. As scabies spreads primarily through extended skin-to-skin contact, the only way for a person to ensure that they do not get it is to avoid such contact completely. Once scabies has entered a household, the best way to prevent the spread is to treat everybody who lives there and be thorough in disinfecting.
This process involves washing and drying all personal items at as high a temperature as possible and thoroughly vacuuming the carpets and furnishings in all of the rooms in which people with scabies have spent time. If it is not possible to wash, dry clean, or disinfect an item, a person should put it in a plastic bag, seal it, set it aside, or take other steps to make sure that no one comes into contact with it for 72 hours.
It is not necessary to fumigate a living space if someone there has scabies. People can have scabies for 4—8 weeks before they show symptoms. Scabies mites can live on the human body for 1—2 months. It should be treated quickly to stop it spreading. The spots may look red. They are more difficult to see on dark skin, but you should be able to feel them. The scabies rash usually spreads across the whole body, apart from the head. However, older people, young children and those with a weakened immune system may develop a rash on their head and neck.
Many other things can cause itchy skin and rashes in babies and children. Scabies is not usually a serious condition, but it does need to be treated.
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