Scabies is caused by Sarcoptes scabiei (also called human itch mite), a parasite (an organism that lives in or on another organism). The mite is a small, eight-legged insect that burrows into the skin to feed, live, and lay eggs. Scabies can be transmitted by physical contact: between people by skin-to-skin contact or through fomites (objects that can carry an infection). For example, sharing clothes or bedding with an infected person can lead to transmission of scabies. The mites burrow and lay eggs under the top layer of the skin, which leads to intense itching. Scabies is found worldwide and can affect people of all ages, races, and income levels, so anyone can get scabies. It is common in children and crowded populations, such as jails and nursing homes.
There is a form of scabies called “crusted, or Norwegian, scabies”. Crusted scabies can be found in the elderly, immunocompromised (weak immune system), or people who are not able to feel the itch or scratch (paralysis for example). These people may not have the usual itchy skin rash. Instead, they have thick crusts and vesicles (fluid-filled sacs) on their skin that contain a lot of mites, making them very contagious. However, both forms of scabies can be treated with medications. The medication takes time to work and needs to kill both the mites and the eggs to completely get rid of the infection.
Signs and Symptoms
- The most common symptom of scabies is an intense, pruritic (itchy) skin rash that is usually worse at night. People may lose sleep because they are so itchy.
- The most common sites are between the fingers, wrist, elbow, armpits, and waist, but it can be found almost anywhere on the body.
- The skin rash looks like tiny, raised, gray-white or skin-colored “bumps” in a line; these are the burrow sites of the mites as they burrow under the skin. They are commonly found in between fingers, in skin folds, and on the genitals or breast.
- The skin rash may also look like pimples, eczema, insect bites
- Scratching at the rash can cause skin sores. These sores can become infected with bacteria such as Staphylococcus aureus.
- After being infected, it may take up 2-6 weeks for symptoms to appear. They are still contagious even when the symptoms are not present.
- Scabies in babies and children can be found all over the body, including the palms and soles. It can be very bothersome and they may not want to eat or sleep.