dermatologic disorders
Scabies
Etiology of Scabies
Scabies is caused by the miteSarcoptes scabieivar.hominis, an obligate human parasite that lives in burrowed tunnels in the stratum corneum. Scabies is easily transmitted from person to person through physical contact; animal and fomite transmission probably also occurs. The primary risk factor is crowded conditions (as in schools, shelters, barracks, and some households); there is no clear association with poor hygiene. For unknown reasons, crusted scabies is more common among patients who are immunosuppressed (eg, those with HIV infection, hematologic cancer, chronic corticosteroid or other immunosuppressant use), patients with severe physical disabilities or intellectual disability, and Australian Aborigines. Infestations occur worldwide ( Etiology reference ). Patients in warm climates develop small erythematous papules with few burrows. Severity is related to the patient’s immune status, not geography. 1.Romani L, Steer AC, Whitfeld MJ, et al: Prevalence of scabies and impetigo worldwide: a systematic review.Lancet Infect Dis15(8):960-967, 2015. doi: 10.1016/S1473-3099(15)00132-2 