What is Scabies?

Scabies is an intensely itchy and contagious mite infestation. The most common symptoms are severe itchiness and a pimple-like rash. Historically known as “the seven year itch”.

The scabies rash typically develops 2-6 weeks after exposure. The most common complaint is itching which is intensified at night. Scabies typically presents with “burrows”  (linear, curved slightly elevated bumps) most commonly found near finger webs, wrists, sides of hands and feet, the penis, buttocks and skin folds. On infants, palms and soles may be affected.

Scabies is caused by infection with the female mite Sarcoptes scabiei. The mites burrow into the skin to live and deposit eggs. The symptoms of scabies are due to an allergic reaction to the mites. Often only between ten and fifteen mites are involved in an infection. Scabies is most often spread during a relatively long period of direct skin contact with an infected person. Spread of disease may occur even if the person has not developed symptoms yet. Crowded living conditions such as those found in child care facilities, group homes, and prisons increase the risk of spread. Crusted scabies is a more severe form of the disease. It typically only occurs in those with a poor immune system and people may have millions of mites, making them much more contagious. In these cases spread of infection may occur during brief contact or via contaminated objects. The mite is very small and usually not directly visible. Diagnosis is based on the signs and symptoms.

A number of medications are available to treat those infected, including permethrin, crotamiton and lindane creams and ivermectin pills. Sexual contacts within the last month and people who live in the same house should also be treated at the same time. Bedding and clothing should be washed in hot water and dried in a hot dryer. Symptoms may continue for two to four weeks following treatment. If after this time there continue to be symptoms retreatment may be needed.

Scabies is one of the three most common skin disorders in children, along with ringworm and bacterial skin infections. As of 2010 it affects approximately 100 million people (1.5% of the world population) and is equally common in both sexes. The young and the old are more commonly affected. It also occurs more commonly in the developing world and tropical climates. The word scabies is from Latin: scabere, “to scratch”. Other animals do not spread human scabies. Infection in other animals is typically caused by slightly different but related mites and is known as sarcoptic mange.