Scabies is a highly contagious infestation of the skin caused by a parasitic mite. It is typically characterized by severe itching in various areas such as in between fingers, in the armpits, or around the genitals. It is one of the most common diseases of the skin, especially in developing countries.
Scabies is caused by the female human mite (Sarcoptes scabiei var hominis), a small parasite which burrows into a person’s skin. The parasite then lays eggs as it moves through the skin, triggering an immune response and leading to intense itching. Prolonged skin-to-skin contact with a person with scabies or contact with their clothes, towels, or beddings can lead to another person getting the disease; the mites can also be spread to another person through sexual contact. Children younger than 15 years of age and adults older than 65 years have a higher risk of getting scabies. Living in close quarters with others such as in a nursing home or military barracks or having a weakened immune system can also increase one’s risk of having the disease.
Symptoms of scabies include intense itching (especially at night), and skin lesions or bumps which are often linear because of the way mites burrow into the skin. These lesions are often found on wrists, finger webs, elbows, soles of feet, ankles, back, buttocks, and armpits; in infants, these vesicles may be seen on their heads. In more severe cases, the infested area may appear crusty, or become infected and discharge pus. If people who live together experience the same symptoms and exhibit similar lesions, they should be investigated for scabies which often present this way because it is highly contagious.
A diagnosis can be made after asking about a person’s symptoms and medical history, and conducting a physical examination. A sample from the lesions could be taken and examined under a microscope to confirm the diagnosis. Treatment involves using a topical scabicide such as Permethrin cream 5% which is applied all over the body: from the neck, behind the ears, to the ankles and feet. Oral ivermectin may be considered in patients who do not recover from using topical medications. Complications, such as a bacterial infection on top of the scabies, should also receive prompt and appropriate treatment. If the itchiness continues to bother the patient, he/she can use antihistamines or corticosteroid creams (under the supervision of a doctor) to get rid of the itching. In order to fully eradicate scabies, the patient and everyone who lives with him or her should also receive the treatment at the same time.
To reduce the chance of scabies,
• avoid skin-to-skin contact with a person diagnosed to have scabies or has an undiagnosed itchy rash
• avoid sharing clothes, towels, linens, and beddings with an infected person
• avoid sharing the same bed All contaminated items used by the infected person such as clothes, towels, and beddings should be properly disinfected by soaking them in boiling water, and thoroughly drying them. It is also advised to leave these items for at least 3 days before using them again.