Symptom Criteria for COVID‐19 Testing of Heath Care Workers

Clemency, Brian M; Varughese, Renoj; Scheafer, Danielle K; Ludwig, Brian; Welch, Jacob V; McCormack, Robert F; Ma, Changxing; Nan, Nan; Giambra, Theresa; Raab, Thomas

BACKGROUND: Limitations on testing availability has been a challenge during the COVID‐19 pandemic. An evidence based symptom criteria for identifying heath care workers (HCW) for testing, based on the probability of positive COVID‐19 test results, would allow for a more appropriate use of testing resources. METHODS: This was an observational study of outpatient COVID‐19 testing of HCW. Prior to testing, HCW were asked about the presence of 10 symptoms. Their responses were then compared to their subsequent pharyngeal swab COVID‐19 Polymerase Chain Reaction test results. These data were used to derive and evaluate a symptom based testing criteria. RESULTS: 961 HCW were included in the analysis, of which 225 (23%) had positive test results. Loss of taste or smell was the symptom with the largest positive likelihood ratio (3.33). Dry cough, regardless of the presence or absence of other symptoms, was the most sensitive (74%) and the least specific (32%) symptom. The existing testing criteria consisting of any combination of one or more of three symptoms (fever, shortness of breath, dry cough) was 93% sensitive and 9% specific (AUC = 0.63, 95% CI: 0.59 – 0.67). The derived testing criteria consisting of any combination of one or more of two symptoms (fever, loss of taste or smell) was 89% sensitive and 48% specific (AUC = 0.75, 95% CI: 0.71 – 0.78). The hybrid testing criteria consisting of any combination of one or more of four symptoms (fever, shortness of breath, dry cough, loss of taste or smell) was 98% sensitive and 8% specific (AUC = 0.77, 95% CI: 0.73 – 0.80). CONCLUSION: An evidence based approach to COVID‐19 testing which at least includes fever and loss of taste or smell should be utilized when determining which HCW should be tested.