dimas 
Share this
What’s scabies?
Human scabies is caused by the human itch mite (Sarcoptes scabiei), which burrows into the skin and lays its eggs, leaving behind a rash.
- Human scabies is caused by the human itch mite (Sarcoptes scabiei, variation or subtype hominis). This itch mite burrows into the upper layers of skin and lays its eggs in the skin.
- It is found worldwide and often causes outbreaks in places where people are living close together, such as dormitories, nursing homes, institutions, or prisons.
- The rash often includes areas such as the web spaces of the fingers, wrists, beltline, feet, scrotum, and areolas, but other areas may get infected.
How do you get scabies? Is scabies contagious?
- Scabies is contagious. However, it usually requires fairly long skin-to-skin contact with an infested person (for example, carrying a person, sleeping with the person, or sexual partners).
- Infrequently, it may be contagious through contact with clothing or bedding, but this form of transfer of scabies is thought to be very infrequent.
- In general, most people who become infested with scabies usually have about 10-15 itch mites on their body.
- One exception to this rule is a scabies infestation that is seen less frequently called crusted or Norwegian scabies, in which large areas of skin are infected with huge numbers (thousands) of itch mites; a person with this type of scabies is highly contagious.
- Although pets can become infested with similar itch mites, they are not usually spread from humans to animals or from animals to humans.
How long is scabies contagious?
- As long as an individual has about 10 to 15 itch mites on their body and has skin-to-skin contact with an uninfested person, that person is contagious for scabies and can pass the organisms to others.
- In addition, a person who has recently acquired scabies and is in the incubation period (without symptoms) is also contagious for scabies.
- People usually know if they have scabies from the presence of a very itchy rash that has little tendrils that extend out of an area of itchy rash (these are the burrows that the itch mite makes in the skin layers), especially if they have noticed similar skin changes on a person with whom they may have had close contact.
- Some physicians may do skin scrapings and, with fairly common laboratory stains, may identify the mite and/or its eggs or fecal matter in the skin scrapings viewed with a microscope.
- In young children, pinkish-brown nodules may form on the skin. The incubation period for scabies can be up to eight weeks; the infested person can be contagious during this period.
What causes scabies?
- Scabies is spread by direct and usually prolonged skin-to-skin contact with a person who has the disease.
- Indirect spread can sometimes occur through contaminated clothing or towels.
- Crusted or Norwegian scabies is highly contagious, both from direct contact and indirect contact (from clothing, bedding, towels, for example) because of the very high concentration of mites.
How do you get rid of scabies? Are there home remedies for scabies?
- Scabicides like permethrin are used topically (spread onto skin) to kill the itch mites.
- Usually, a cream or lotion is applied from the neck down to the feet, and the cure results in remission and finally disappearance of the rash.
- However, sometimes people may seem to be cured only to have itching and the rash return in a few weeks.
- This may be due to inadequate treatment that allows the eggs to survive and hatch or may be due to inadequate cleaning of clothing or bedding (scabies mites are killed by hot water and dryer heat, or dry cleaning, and cannot survive more than two or three days away from human skin) or simply due to contacting someone who has scabies.
- If there is no further symptom development about two to four weeks after treatment, most people will be cured of scabies.
Should I see a doctor for scabies treatment?
- If you or someone close to you has scabies, contact a physician for treatment and for advice about who else may benefit from treatment (for example, sexual partners, family members).
- Patients with crusted scabies require isolation and/or barriers (gloves, gowns, for example) to protect others from the mites; such patients often are hospitalized and also tested for underlying health problems (such as immunosuppression).
How Do I Know if I Have Scabies?
Symptoms of scabies include feeling very itchy, itchy rash and small blisters, scales, burrows.
Scabies is a skin infestation caused by mites. Scabies mites can live up to two months on a person’s body, and up to three days on surfaces. They will die if exposed to heat above 122 degrees Fahrenheit.
Symptoms of scabies
Symptoms of scabies include:
- Feeling very itchy (particularly at night)
- Itchy rash with small pimple-like structures
- Small blisters
- Scales
- Small burrows, especially on:
- The webbing of the fingers
- Elbow
- Knee
- Penis
- Breasts
- Shoulder blades
- Sores (caused by scratching)
The burrows are caused by the female mites burrowing down into the skin to lay their eggs.
It takes between four and eight weeks from the time of infection for scabies to show up in a person who has never had it before. It takes only a few days for it to show up in people who have previous scabies experience. Scabies is contagious even before symptoms show up.
Types of scabies
Some scabies infections can turn into Norwegian scabies, or crusted scabies, in people with compromised immune systems. The difference between regular scabies and crusted scabies is the severity.
Symptoms of crusted scabies include:
- All the regular symptoms of scabies
- Thick crusts of skin
- Larger numbers of mites and eggs
People with regular scabies may have 10-15 mites. People with crusted scabies can have thousands.
People with crusted scabies are incredibly contagious and need to receive immediate medical treatment.
The human itch mite Sarcoptes scabiei var. hominis causes scabies. The mites live everywhere in the world and can affect any kind of person. Race and class do not play a factor in scabies infections.
Scabies spreads from prolonged skin to skin contact. A simple hug or kiss will likely not spread it. It does spread where people are often in close contact like in nursing and childcare facilities.
In adults, it often spreads through sexual contact. It can also spread through sharing items used by someone who has scabies like towels or linens. It spreads easily in the same household.
People with scabies are contagious, but it is much easier for the infection to spread from someone who has crusted scabies.
Diagnosis/tests for scabies
Doctors may diagnose a scabies infection by looking at it. They may also take a sample of a mite, mite excrement, or mite eggs to properly identify the organism before diagnosing.
Treatments for scabies
Doctors treat scabies with scabicides, prescription medications that kill scabies mites, and eggs. They are usually a lotion or cream that you apply to your entire body from the neck down. In infants, you should also put it on the head and neck.
Doctors recommend that everyone in the household, sexual partners, and anyone who has had prolonged skin-to-skin contact with the infected person receive treatment at the same time. Doing so gets ahead of asymptomatic spread and prevents reinfection.
Treatment options include:
- 5% permethrin cream
- 10% crotamiton cream
- 25% benzyl benzoate lotion
- 5%-10% sulfur ointment
- 1% lindane lotion
Doctors may prescribe the oral medication ivermectin to patients with crusted scabies.
Sores caused by scratching may get bacterial infections that require additional treatment with antibiotics.
How Long Does It Take to Treat Scabies?
Scabies is an infestation of a highly contagious, microscopic skin parasite. Scabies are treated with scabicides that sometimes take more than one application to work. If itching and other symptoms continue more than four weeks after initial treatment, you should see a doctor.
Scabies is an infestation of a highly contagious, microscopic skin parasite. It can spread between anyone through skin-to-skin contact and through sharing clothes, towels, or other materials that touch the skin. Scabies usually isn’t serious, but it can be harmful for people with certain health conditions. It can also lead to dangerous infections without proper treatment. You can get rid of scabies with a doctor’s help.
Scabies is a very itchy skin condition caused by a small mite burrowing into your skin. It is not an infection but an infestation as the mite lays eggs.
Symptoms of scabies
If you’ve gotten scabies for the first time, you might not notice any symptoms for up to six weeks. Then, an intensely itchy rash will appear on your skin. The itching may be severe enough that it affects your sleep. Rashes usually form a line of small red bumps, which can look like acne, hives, eczema, or other skin conditions. Scratching these rashes may lead to infections due to bacteria and dirt on your fingers getting into open sores.
Causes of scabies
Sarcoptes scabiei is the mite, or microscopic bug, that causes scabies. Female scabies mites burrow into your skin, where they lay eggs that hatch and reproduce with each other, maintaining the infestation. They can burrow anywhere on your body, but common areas for rashes to develop are your wrists, knees, genitalia, breasts and nipples, underarms, and between your fingers.
A severe and more contagious type of scabies is called crusted scabies or Norwegian scabies, which is more common in elderly people and those with weakened immune systems. With crusted scabies, a much higher number of mites live on the skin, and can make it look crusty in certain places. Crusted scabies spreads through clothing, towels, and other objects that touch the skin more often than regular scabies, which usually spreads through skin-to-skin contact.
Who gets scabies?
Scabies spreads through close contact between people, especially through skin-to-skin contact, and can take as little as 15 to 20 minutes to be transmitted. Sexual partners, nursing home residents and employees, children and workers at child care facilities, and people living in close quarters are common examples of who gets scabies, but anyone can get it if they are exposed.
Diagnosis of scabies
A doctor will be able to provide a scabies diagnosis. They will ask about your symptoms and who you’ve been in contact with. The doctor will also need to examine your skin, and may painlessly take a small sample of your skin to inspect it under a microscope for scabies mites and eggs.
A doctor needs to officially diagnose you with scabies to prescribe proper treatment. All effective scabies treatments require a doctor’s prescription — no scabies medication is sold over the counter.
Medications
The only proven way to treat scabies is with scabicide, a type of medication that kills scabies mites and eggs. Most scabicides are creams or lotions that you apply all over the skin from head to toe, usually before bed, and wash off in the morning. These topical medications typically contain one of the following ingredients:
- Permethrin
- Crotamiton
- Lindane
- Sulfur
Scabicides sometimes take more than one application to work. If itching and other symptoms continue more than four weeks after initial treatment, contact your doctor — you may need additional treatment. If these medications still don’t work, or if you aren’t able to use the above products due to pregnancy, allergy, health conditions, or other reasons, a doctor may prescribe a pill containing the ingredient ivermectin.
Everyone who has been in close contact with a person with scabies, including sexual partners and household members, needs treatment even if they don’t show symptoms. Contacts should receive treatment as close to the same time as possible to prevent reinfestation.
Home care
Home care by itself won’t get rid of scabies, but it can help prevent future infestations by killing all existing mites.
Wash bedding, clothing, towels, and other fabrics that touch the skin with hot water and, if possible, dry on a hot cycle or get them dry-cleaned. For whatever objects can’t be washed, don’t touch them for at least 72 hours. If possible, seal these objects in a closed plastic bag for at least three days. When they’re not inside the skin, scabies mites will die within that time frame.
No alternative therapies have yet proven to be effective in preventing or treating scabies. Surgery usually is not necessary.
Risks and side effects of scabies treatment
Scabies could be misdiagnosed, as it shares symptoms with other drug interactions and skin conditions. Using scabicide more often than directed could worsen your rash and itching. Make sure to follow your doctor’s instructions and follow up with any questions or concerns.
What Are Scabies?
Scabies are eight-legged human itch mites that cause a contagious skin condition. These microscopic mites burrow into the skin and cause symptoms of itching and rash. It takes about three weeks for these mites to incubate, but once infested, re-infestation may happen even faster than that.
How Do You Get Scabies?
Anyone can get scabies. Infestations can be found all over the world and the mite is transmitted by direct and prolonged skin-to-skin contact with a person who has the disease. Sexual contact is the most common way these mites are transmitted.
Transmission can also happen from parents to children, particularly mother-to-infant. The mite can only survive about 48 to 72 hours without human contact, so it is uncommon, though possible, for them to spread through infested bedding or furniture.
How Long Does Scabies Last?
Scabies mites can only live about 72 hours without human contact, but once on a person, the mites can live up to two months. Mites survive longer in colder conditions with higher humidity. Once on a person, mites can burrow into the skin, and symptoms usually begin three to six weeks after infestation.
Can You Catch Scabies from a Dog or Cat?
Animals do not spread the same types of mites that cause human scabies, so it is not possible to catch them from a dog or cat. The type that can infest pets is called “mange.”
Mange mites can spread to humans and cause minor itching and redness, but those mites cannot survive or reproduce on human skin and will die out on their own, limiting symptoms in humans. People do not need to be treated if they come into contact with mange, but dogs and cats must be treated because mange can spread and cause fur loss, and scaly and itchy skin in pets.
What Are the Signs and Symptoms of Scabies?
Symptoms of scabies are usually itching (which tends to be more intense at night), and a pimple-like rash. Scabies rash can appear on any part of the body, but the most common sites are wrists, elbows, armpits, the skin between the fingers and toes and around the nails, and skin usually covered by clothing such as the buttocks, belt line, nipples, and penis. Infants and young children may have the rash on their head, face, neck, palms, and soles.
In some patients with weakened immune systems, scabies rash may become crusted.
What Does Scabies Infection Look Like?
Scabies infestations often look like small red pimple-like bumps on the skin. The bumps may be crusty. They may also be accompanied by “burrows,” or thin gray, brown, or red lines that radiate from the bumps. They may be hard to see, and can look like scratch marks.
What Does a Scabies Infection Feel Like?
Scabies cause intense itching, often worst at night. The itching starts as a minor nuisance and progresses to a point where the infested person cannot sleep.
How Are Scabies Tested for and Diagnosed?
Scabies are usually diagnosed by the patient’s history and a physical examination of the lesions (bumps). Other tests that may be done include:
- Skin scraping to identify the mites or eggs
- Dermoscopy, which uses a handheld dermoscope to allow closer visual examination of the skin to look for mites
- Adhesive tape test in which a doctor uses strong adhesive tape applied to the skin lesions and then pulled off and viewed under a microscope to check for mites
Cream Applications
There are no over-the-counter approved treatments for scabies. A doctor must prescribe treatment. A first-line treatment may involve a topical cream, such as permethrin (Elimite), which is applied directly to the skin, from the neck to the soles of the feet. It should be left on overnight and then washed off 8 to 14 hours later. Usually a second application after 1 to 2 weeks is recommended.
Other topical treatments include crotamiton (Crotan, Eurax) cream or lotion, lindane (not usually used as a first-line treatment due to risk of seizures), sulfur ointment, and benzyl benzoate (not available in the United States).
Oral Medication
In some cases, oral ivermectin may be used, particularly in cases where scabies covers a large part of the body and is crusted. It is also often used in settings such as nursing homes where there may be widespread outbreaks. The Centers for Disease Control (CDC) recommends a dose of 200 mcg/kg as a single dose, repeated in two weeks. The advantages of oral ivermectin are that it is easy to use and it does not cause related skin problems. However, oral ivermectin can cause unwanted side effects so it is not always the first choice treatment.
Antihistamines
To get relief from the symptom of itching, some over-the-counter antihistamines such as diphenhydramine (Benadryl) may help control the itch and allow sleep.
Wash Linens and Bedclothes
Scabies mites do not survive more than 72 hours without human contact. It is usually sufficient to machine wash bed linens and clothing in hot water and dry on high heat, or have the items dry-cleaned. It is not necessary to have furniture or carpets cleaned as the mites will die off on their own in a few days without human contact.
More Scabies Tips
Some additional ways you can treat scabies mites or prevent them from spreading include:
- Make sure everyone who is in contact with the infested person is treated, particularly those who come in frequent, close contact with that person (i.e., sexual partners, people who live with the infested person, small children and infants cared for by an infested parent).
- Keep fingernails and toenails well trimmed and clean of any mites or eggs.
- Thoroughly vacuum carpets, furniture, and car interiors. Use extra caution vacuuming after someone who has crusted mites, as these are more contagious. Discard the vacuum cleaner bags or clear out the dirt receptacle when done.
- Avoid scratching bumps or lesions.
- Keep open sores clean.
- Remember that once treatment starts it may still take a few days for itching and other symptoms to subside. If it does not go away, see a doctor.
Are Cases of Scabies Often Misdiagnosed?
Scabies infestations can often resemble other skin conditions. It may look like small pimples, or mosquito bites. It may also look like eczema or tinea (ringworm, athlete’s foot, and jock itch). It is important to see a doctor to receive the correct diagnosis and treatment.
In What Special Situations Can Scabies Be More Easily Spread?
Scabies may spread more easily in nursing homes and other extended-care facilities because of the close contact of residents and staff. These mites can also more easily spread among people with compromised immune systems, such as people with HIV/AIDS, or cancer.
What Is “Norwegian Scabies”?
Crusted scabies, sometimes called “Norwegian scabies,” is a serious complication of this skin disease. Crusted scabies tends to occur more often in patients with compromised immune systems due to conditions such as HIV/AIDS or cancer, or in the elderly, and in patients with Down syndrome.
Patients with crusted scabies have large numbers of scabies mites and are very contagious. It can affect any area of the body but the scalp, hands, and feet are most commonly affected. The scales become warty, with crusts and fissures. Lesions may have an unpleasant odor. Nails may be thick and discolored, and patients may or may not have symptoms of itching.
About Author
