Outbreak Investigation of COVID-19 Among Residents and Staff of an Independent and Assisted Living Community for Older Adults in Seattle, USA

This Journal of the American Medical Association case study reports on a survey of 142 residents and staff exposed to persons with COVID-19 among residents and staff of an independent/assisted living community in Seattle, Washington, USA. Testing was carried out on 80 residents; 62 were women (77%), with mean age of 86 (range, 69-102) years. Covid-19 was detected in 3 of 80 residents (3.8%); none felt ill, 1 male resident reported resolved cough and 1 loose stool during the preceding 14 days. Virus was also detected in 2 of 62 staff (3.2%); both were symptomatic. One week later, resident coronavirus testing was repeated and 1 new infection detected (asymptomatic). All residents remained in isolation and were clinically stable 14 days after the second test.

The study reveals that symptom screening failed to identify residents with infections and all 4 residents with the virus remained asymptomatic after 14 days. Although 1 asymptomatic infection was found on retesting, a widespread facility outbreak was avoided. Compared with skilled nursing settings, the study suggests that in assisted/independent living communities, early surveillance testing was a better strategy for identifying staff and older adults with Covid-19 than symptom screening, preventing a facility-wide outbreak. Furthermore, adherence to social distancing and preventive guidelines may also contribute to interruption of the transmission of coronavirus.