Scabies is a severely itchy skin infestation caused by the host-specific mite Sarcoptes scabiei var. hominis. Scabies is an easily treatable infestation and remains widespread mainly because of diagnostic difficulties, inadequate treatment of patients and their contacts, and improper environmental control measures. Scabies is a great clinical mimic. The spectrum of skin manifestations and associated symptoms often results in delayed diagnosis. In fact, the term "7-year itch" was first used in reference to persistent, undiagnosed infestations of scabies
Scabies is a global public health problem, affecting persons of all ages, races, and socioeconomic groups. Worldwide, an estimated 300 million cases occur annually. [5] Overcrowding, delayed diagnosis and treatment, and poor public education contribute to the prevalence of scabies in industrial and developing nations.
Prevalence rates are higher in children and sexually active individuals than in other persons. Patients with poor sensory perception due to entities such as leprosy and persons with immunocompromise due to conditions such as status post transplantation, human immunodeficiency virus (HIV) disease, and old age are at particular risk for the crusted variant. These populations present with clinically atypical lesions and often are misdiagnosed, thus delaying treatment and elevating the risk of local epidemics.