Comparing Clinical Characteristics of Influenza and Common Coronavirus Infections Using Electronic Health Records

Li, Dadong; Wolk, Donna M; Cantor, Michael N

BACKGROUND: We compared outcomes in inpatients and outpatients, pre-COVID-19, who were infected with either coronavirus or influenza. METHODS: Using deidentified electronic health records data from the Geisinger-Regeneron partnership, we compared patients with RT-PCR–positive tests for the 4 common coronaviruses (229E, HKU1, NL63, OC43) or influenza (A and B) from June 2016 to February 2019. RESULTS: Overall, 52 833 patients were tested for coronaviruses and influenza. For patients ≥21 years old, 1555 and 3991 patient encounters had confirmed positive coronavirus and influenza tests, respectively. Both groups had similar intensive care unit (ICU) admission rates (7.2% vs 6.1%, P = .12), although patients with coronavirus had significantly more pneumonia (15% vs 7.4%, P < .001) and higher death rate within 30 days (4.9% vs 3.0%, P < .001). After controlling for other covariates, coronavirus infection still had a higher risk of death and pneumonia than influenza (odds ratio, 1.64 and 2.05, P < .001), with no significant difference in ICU admission rates. CONCLUSIONS: Common coronaviruses cause significant morbidity, with potentially worse outcomes than influenza. Identifying a subset of patients who are more susceptible to poor outcomes from common coronavirus infections may help plan clinical interventions in patients with suspected infections.