This article discusses how scabies spreads. It also explains ways to diagnose, treat, and prevent the disease.

How Does Scabies Spread?

Scabies is usually passed from an infected person to others during prolonged, direct skin-to-skin contact like holding hands. It takes about 10 minutes of contact for the mite to pass from the infected host to another person.

Scabies is easily passed among people who share the same household. Scabies infestations can be found in places where people interact and live in crowded conditions. This includes childcare centers, hospitals, and assisted living facilities, where staff can spread the disease from one person to another.

Children can become infected with scabies by their parents. Among young adults, the disease is often spread during sexual contact.

While animals can become infected with a form of scabies, called mange, it involves a different type of mite that can’t reproduce on humans.

Though uncommon, scabies can be passed from contact with the bedding, clothes, and furniture of an infected person. This indirect transmission is more likely to occur when the infected person has crusted scabies, a form of the disease in which there are large numbers of scabies mites and eggs. Crusted scabies is more common among people who have a weakened immune system or neurological disease.

How Long Is Scabies Contagious?

If you have scabies, you’re considered contagious until you receive your first treatment. You can pass scabies to another person from the time you’re infested with the mites until you begin treatment.

The time between infestation and symptoms is called the incubation period. The first time you have scabies, it can take four to eight weeks for symptoms to appear. If you’ve previously had a scabies infection, symptoms typically emerge within four days after exposure.

Once you are infected, you can spread the disease even if you don’t have symptoms.

Scabies Causes

Scabies is caused by the Sarcoptes scabiei mite. This microscopic, eight-legged mite burrows into the top layer of your skin, where it lays eggs.

The eggs hatch and create new adults that burrow within two weeks. Their babies maintain the cycle of burrowing and egg-laying until the entire infestation is treated.

Your immune system recognizes the mites and their waste as potentially dangerous organisms, which triggers a response. This results in the itchy, red rash that is common with scabies.

Scabies Diagnosis

The distinct rash and itching that occur with scabies can be mistaken for other health problems like allergies, contact dermatitis, eczema, or psoriasis. Since treatment is necessary to eradicate the scabies mites, it’s important to get an accurate diagnosis, so you can get the right treatment.

Contact your healthcare provider if you experience any of the following symptoms, even if you’re not aware of having had contact with someone who has scabies:

Severe itching, especially at nightRash with red bumps often arranged in a lineCrusty or scaly skinSores that develop as a result of scratching the itchy rash

A healthcare provider’s first steps in diagnosing scabies involve getting a patient history and performing a visual examination of your skin for evidence of scabies. If you are being examined in a dermatology office, your provider may use dermoscopy, which has a lens with 10 times magnification to identify the presence of scabies.

When there are signs of scabies, the Centers for Disease Control and Prevention (CDC) advises healthcare providers to confirm the diagnosis by scraping a skin sample near the affected site. The sample should be examined under a microscope, where the presence of mites, mite eggs, or fecal matter can be detected.

If your diagnosis is unclear, your healthcare provider may take a skin biopsy to confirm the presence of mites. In this procedure, a sample of tissue is removed to be analyzed in a laboratory.

Scabies Treatment

Eradicating scabies requires the use of prescription medications. When used as directed, research shows that these treatments produce comparable results to killing the mites without adverse reactions.

The type of drug used to treat your scabies depends on your condition and other factors, such as your current medications and other health problems. According to the CDC, the infected person and all people who had direct skin-to-skin contact with the infected person in the month before treatment should be treated at the same time to avoid reinfestation.

The following prescription medications are used to treat scabies:

Nix (permethrin) 5% creamEurax (crotamiton) 10% cream or lotionSulfur (5%-10%) ointmentScabene (lindane) 1% lotionNatroba (spinosad) 0. 9% liquidStromectol (ivermectin)

Crusted scabies requires a combination of oral and topical agents that include:

Stromectol (ivermectin) Nix (permethrin) cream 5% Benzyl benzoate 25% (with or without tea tree oil) Keratolytic cream

Based on your condition, you may also need other medications to relieve itching and inflammation or treat an infection, such as the following:

Some possible complications of scabies, especially in the tropics, include:

Bacterial infection Impetigo Abscesses Septicemia Kidney disease Rheumatic heart disease

Antihistamine Pramoxine lotion Antibiotic Steroid cream Nonsteroidal anti-inflammatory drugs (NSAIDs), such as Advil or Motrin (ibuprofen) and Aleve (naproxen)

Scabies Prevention

Since scabies is spread through direct skin-to-skin contact, the most effective way to prevent scabies is to avoid this type of interaction with an infected person. However, since it’s possible to carry the mites without having symptoms, it may not be obvious that you or another person is infected.

Identifying and treating a scabies infection as soon as possible is the best way to prevent its spread. Without treatment, the mites continue to produce eggs and the number of mites on your skin continues to grow. The examination and treatment of your household and sexual and close contacts are also necessary to avoid reinfection.

ChildrenParents of young childrenSexually active young adultsResidents of nursing homes and other community living facilitiesHospitalized patients

In addition to getting treatment, you and your sexual and close contacts should decontaminate all bedding, clothing and towels used within three days of starting treatment. This requires dry cleaning them, sealing them in a plastic bag for at least 72 hours, or washing the items in hot water and drying them in a hot dryer.

Summary

Scabies is caused when the scabies mites burrow into the top layer of your skin to feed and lay eggs. The mites trigger an immune response that causes an intense rash and itching.

Scabies mites are passed through prolonged skin-to-skin contact with an infected person. Since symptoms often occur only after a period of infestation, a person can spread scabies before they know they have it.

It’s key to get an accurate diagnosis of scabies as soon as possible. The disease requires prescribed drugs for treatment. If you become infected, your sexual and close personal contacts should also be treated at the same time. This prevents the spread of the disease and your reinfection.

A Word From Verywell

Having scabies can be frustrating. The itching can be intense, especially at night, which can interfere with sleep. To kill the mites, it’s important to get an accurate diagnosis and treatment as soon as possible. This also reduces the risk of skin damage from scratching or rubbing to relieve the itching.

Unfortunately, scabies isn’t well understood in the United States. There is a misconception that the disease is linked to poor hygiene, which isn’t accurate. Seek support from your healthcare team on ways to avoid feeling isolated. With the right diagnosis and prompt treatment, you can quickly eradicate the disease and relieve symptoms.