Scabies: a neglected parasitic disease we already know how to treat

TheConversation: Mites living in your skin are just the start of the problems that come with having scabies. The highly infectious parasitic condition is linked with extreme itchiness, bacterial infections and kidney damage, plus debilitating social and economic consequences. But we’re not addressing the problem. Although a drug of known safety and efficacy is available, scabies still affects more than 100 million people across the world who can’t break free of illness and reinfection cycles.

Tropical skin disease survey reveals global hotspots

UNSW: The first ever international review of scabies and impetigo has indentified global hotspots and revealed children are disproportionately affected by the debilitating infectious conditions. The systematic review, led by UNSW’s Kirby Institute with collaborators, analysed findings from 48 surveys, mostly from developing countries in the Pacific, Latin America and Africa. The results were published today in The Lancet Infectious Diseases journal.

Scabies

Scabies is an intensely itchy infestation of the skin by the human mite Sarcoptes scabiei var hominis. Scabies affects both sexes, all ages, all ethnic groups, and people of all socioeconomic status. Common routes of transmission are person-to-person skin-to-skincontact with infected family members or contacts at day care, schools, nursing homes, hospitals, and long term care facilities. In adults, scabies is often transmitted from person to person by sexual contact. Infestation with the scabies mite causes a hypersensitivity reaction in the skin which manifests as an intensely itchy rash. The itch seems to affect the trunk and extremities, with characteristic spreading to the face and neck. The incubation period (time from infestation until itching begins) is about 1 month. The diagnosis of scabies is made by history (time of onset of symptoms, location of itch, affected close contacts), physical examination (typical skin lesions and areas of involvement), and confirmation by a skin scraping. The treatment of scabies requires both eliminating the mite from the skin and treating the symptom of itch. In addition, close contacts of a confirmed case (family members, roommates, sexual partners, etc.) require treatment at the same time, whether or not they have symptoms in order to prevent reinfestation or spread to others. Treatments commonly used in the United States to eliminate the scabies mite are Permethrin 5% cream, Lindane 1% cream, Precipitated sulfur, Ivermectin.
More about scabies

Scabies

Author: Dr Lindy P. Fox University of California San Francisco 2008-07-28

What is scabies?

Scabies is an intensely itchy infestation of the skin by the human mite Sarcoptes scabiei var hominis.  It has a global prevalence of 300 million cases per year [Strong and Johnstone 2007; Chosidow 2006].  The mite completes its entire life cycle on humans. Mites do not jump or fly, but can crawl on the skin at a rate of 2.5cm per minute [Chosidow 2006]. The female scabies mite tunnels into the top layer of the skin where she lays 10-25 eggs in burrows that are about 1 cm long [Leone 2007]. Two to three days later, larvae emerge from the burrows, dig new burrows, mature, and mate. This cycle repeats every two weeks [Johnston and Sladden  2005]. The total length of the life cycle is 30-60days [Leone 2007]. In most cases of scabies infestation, there are only 5-15 (average of 12) mites on human skin at a time, except in crusted scabies, where thousands to millions of mites can be present on the skin.