Background: Scabies is a contagious dermatosis caused by human mites, (Sarcoptes scabei, variant hominis). In crusted (Norwegian) scabies, the burden of mite infestation is higher and up to 2 million per person, facilitating easy skin-to-skin transmission and nosocomial transmission. We describe a case of undiagnosed crusted scabies and subsequent transmission to employees in our hospital. Methods: A 90-year-old female was admitted to our 636-bed, nonprofit, academic hospital for 22 days prior to diagnosis of crusted scabies by skin scraping. The patient was admitted to 2 different medical-surgical wards and the medical intensive care unit. We collected healthcare worker (HCW) demographics, including department of service, age, sex, pregnancy, and breastfeeding status in those who were at risk of exposure. We interviewed HCWs at 2 time points and collected information related to infestation, allergies to treatment, acceptance of empiric treatment, and whether employee was furloughed. Results: On initial screening, 20 of 124 at-risk HCWs had symptoms (Fig.). Most had a “new onset raised red rash or new pimple like rash (not on face), or linear rash” and 4 had “new onset uncontrollable itching.” All 124 HCWs were contacted 28 days later. One HCW that had not been compliant with prophylaxis became symptomatic and was diagnosed with scabies by dermatology. Of the remaining 20 HCWs, 3 were still having symptoms (2 had itching and 1 had a rash and a scrape performed by dermatology with confirmation of mites). All 3 were retreated with ivermectin. Overall, 21 of 124 exposed HCWs were ultimately symptomatic. Conclusions: During a 22-day admission of an undiagnosed and unisolated elderly patient with crusted scabies, the scabies mite was transmitted to 21 HCWs for an acquisition rate of 17%. Persistence of symptoms after treatment with permethrin occurred in 14%. The infectivity of this disease necessitates early recognition and infection control measures.