Scabies outbreaks in nursing homes for the elderly: recognition, treatment options and control of reinfestation.

The scabies mite is an ectoparasite able to infest humans. Its clinical presentation is typical, although in immunocompromised, mentally retarded and elderly patients the clinical presentation may be altered. Diagnosis may therefore be difficult in such patient groups, who often reside in nursing homes. Because delay in diagnosis may induce rapid spread of the scabies mite, immediate diagnosis and treatment are necessary. Normal scabies (scabies vulgaris) and crusted scabies (scabies crustosa, scabies norvegica), although sometimes difficult to diagnose, especially in the elderly, are fortunately quite easy to treat. However, the elderly patient may experience toxicity from local or systemic scabicidal treatment. Single cases of scabies vulgaris should be treated with permethrin cream because of its outstanding efficacy and favourable adverse events profile. Scabies outbreaks and cases of scabies crustosa can easily be managed using combination therapy consisting of topical application of permethrin and two oral doses of ivermectin 200 microg/kg (administered 1 week apart). In addition to treatment of the scabies infestation, preventative measures are necessary, particularly in nursing homes.