What is 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.
Causes of scabies
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.