Community COVID-19 activity level and nursing home staff testing for active SARS-CoV-2 infection in Indiana

Blackburn, Justin; Weaver, Lindsay; Cohen, Liza; Menachemi, Nir; Rusyniak, Dan; Unroe, Kathleen T.

Objectives To assess whether using coronavirus disease 2019 (COVID-19) community activity level can accurately inform strategies for routine testing of facility staff for active severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Design Cross-sectional study Setting and Participants 59,930 nursing home staff tested for active SARS-CoV-2 infection in Indiana. Measures Receiver operator characteristic curves and the area under the curve (AUC) to compare the sensitivity and specificity of identifying positive cases of staff within facilities based on community COVID-19 activity level including county positivity rate and county cases per 10,000. Results The detection of any infected staff within a facility using county cases per 10,000 population or county positivity rate resulted in an AUC of 0.648 (95% CI 0.601-0.696) and 0.649 (95% CI 0.601-0.696), respectively. Of staff tested, 28.0% were certified nursing assistants (CNAs), yet accounted for 36.9% of all staff testing positive. Similarly, licensed practical nurses (LPNs) were 1.4% of staff, but 4.7% of positive cases. Conclusions and Implications We failed to observe a meaningful threshold of community COVID-19 activity for the purpose of predicting nursing homes with any positive staff. Guidance issued by the Centers for Medicare and Medicaid Services (CMS) in August 2020 sets the minimum frequency of routine testing for nursing home staff based on county positivity rates. Using the recommended 5% county positivity rate to require weekly testing may miss asymptomatic infections among nursing home staff. Further data on results of all-staff testing efforts, particularly with the implementation of new widespread strategies such as point-of-care testing, is needed to guide policy to protect high risk nursing home residents and staff. If the goal is to identify all asymptomatic SARS-Cov-2 infected nursing home staff, comprehensive repeat testing may be needed regardless of community level activity.