Microscopic mites are the source of scabies, a skin infestation that causes an itchy rash. Scabies spreads through direct contact with an infected person. Scabies most commonly occurs in people who have close physical contact with other, such as children, mothers of young children, sexually active young adults and people living in nursing homes, according to the American Academy of Dermatology. Scabies treatment is aimed at killing mites and their eggs.
Identification
Scabies mites burrow into the skin, laying eggs that produce an allergic reaction weeks after exposure to the mites. When mites hatch from the eggs, they make their way to the skin surface, eventually developing into adult mites. If the mite is removed from the skin by scratching and lands in bedding or clothing, others who come in contact with the items can be infested.
Symptoms
Scabies symptoms may not appear until four to six weeks after infestation if a person has not had scabies before and one to four days after infestation if the person has previously had scabies, according to the Centers for Disease Control and Prevention. Scabies causes a red, itchy rash that looks like an outbreak of pimples or hives on the skin. Small raised areas may appear on the skin as the female burrows beneath the skin to lay her eggs. Burrows are more likely to be found on shoulder blades, the breasts, penis, between the fingers and in the skin folds of the elbow, knee or wrist because the mites are drawn to the warmer areas of the body.
Considerations
A severe form of scabies, called Norwegian or crusted scabies, may affect elderly or disabled people or people who have weak immune systems. Affected areas of the skin are covered with a thick crust containing thousands of mites and eggs. People who have Norwegian scabies are very contagious, but people who have this form of the infestation may not suffer from itching or a rash.
Treatment
Topical creams and lotions containing permethrin or lindane are applied to the skin to kill mites and eggs. A second application of cream or lotion may be needed one week after the first application to kill any lingering mites or eggs. Because symptoms may not occur until weeks after exposure, it is important to treat everyone living in the same household, whether everyone is showing signs of infestation or not. If itching is severe, antihistamines can be used to relieve symptoms. Topical medications are unable to penetrate the crusts of Norwegian scabies and oral ivermectin may be prescribed in these cases.
Prevention
When scabies is diagnosed in one person, taking appropriate precautionary steps can prevent the spread to other people. The AAD recommends washing clothing or bedding with the hottest water possible. Items that can't be washed can be dry cleaned or placed in a hot dryer for 30 minutes. Vacuuming upholstery and carpets is an important step in stopping the spread of scabies. Vacuum cleaner contents should be placed in a trash can outside the home to prevent reinfestation.
