Human Skin Parasites
Scabies is caused by mites in the genus Sarcoptes. It is commonly diagnosed as unspecified parasitic dermatitis. These mites burrow into the skin and spend their entire life cycle in and on the skin. Lesions caused by scabies are very distinctive and tend to be concentrated on the web spaces between the fingers and toes and in axillary and genital areas. Burrows can be identified, and scrapings will contain mites, eggs and feces. Itching caused by scabies is intense. However, scabies is over-diagnosed. Scabies occurs in epidemics among susceptible individuals, then generally becomes rare since once someone is infected they are then immune. It is uncommon in the U.S. in most communities and tends to be encountered more frequently in homeless populations than elsewhere.