Asymptomatic and Presymptomatic SARS-CoV-2 Infections in Residents of a Long-Term Care Skilled Nursing Facility — King County, Washington, March 2020

Abstract
Following identification of a case of coronavirus disease 2019 (COVID-19) in a health care worker, 76 of 82 residents of a long-term care skilled nursing facility were tested for SARS-CoV-2; 23 (30.3%) had positive test results, approximately half of whom were asymptomatic or presymptomatic on the day of testing.