Diagnosed and Undiagnosed COVID-19 in US Emergency Department Healthcare Personnel: A Cross-Sectional Analysis

Mohr, Nicholas M.; Harland, Karisa K.; Krishnadasan, Anusha; Eyck, Patrick Ten; Mower, William R.; Willey, James; Chisolm-Straker, Makini; Lim, Stephen C.; McDonald, L. Clifford; Kutty, Preeta K.; Hesse, Elisabeth; Santibanez, Scott; Talan, David A.; Bahamon, Monica; Carlson, Jestin N.; Driver, Brian; Faine, Brett; Galbraith, James; Giordano, Philip A.; Haran, John P.; Higgins, Amanda; Hinson, Jeremiah; House, Stacey; Idris, Ahamed H.; Kean, Efrat; Krebs, Elizabeth; Kurz, Michael C.; Lee, Lilly; Liang, Stephen Y.; Montoy, Juan Carlos C.; Moran, Gregory; Nandi, Utsav; Pathmarajah, Kavitha; Paxton, James H.; Perez, Yesenia; Richardson, Lynne D.; Rodriguez, Robert M.; Rothman, Richard; Schrading, Walter A.; Shuck, Jessica; Slev, Patricia; Smithline, Howard A.; Souffront, Kimberly; Steele, Mark; Stubbs, Amy; Swanson, Morgan; Tiao, Josh; Torres, Jesus R.; Trent, Stacy; Uribe, Lisandra; Venkat, Arvind; Volturo, Gregory; Wallace, Kelli; Weber, Kurt D.

Objective To determine the percentage of diagnosed and undiagnosed SARS-CoV-2 infection among a sample of US ED health care personnel (HCP) before July 2020. Methods Cross-sectional analysis of ED HCP in 20 geographically diverse university-affiliated EDs from May to July 2020, including case counts of prior laboratory-confirmed COVID-19 diagnoses among all ED HCP, then serology (with confirmatory testing) and reverse transcriptase-polymerase chain reaction (RT-PCR) testing in a sample of volunteers without a previous COVID-19 diagnosis. HCP were categorized as clinical (physicians, advanced practice providers, and nurses) and non-clinical staff (clerks, social workers, and case managers). Previously undiagnosed infection was based on positive SARS-CoV-2 serology or RT-PCR among HCP without prior diagnosis. Results Diagnosed COVID-19 occurred in 2.8% (193/6,788) HCP, and the prevalence was similar for nonclinical and clinical staff (3.8% vs. 2.7%; odds ratio, OR 1.5, 95% confidence interval, 95% CI 0.7-3.2). Among 1,606 HCP without previously diagnosed COVID-19, 29 (1.8%) had evidence of current or past SARS-CoV-2 infection. Most (62%, 18/29) who were seropositive did not think they had been infected, 76% (19/25) recalled COVID-19-compatible symptoms, and 89% (17/19) continued to work while symptomatic. Accounting for both diagnosed and undiagnosed infections, 4.6% (95% CI 2.8-7.5%) of ED HCP were estimated to have been infected with SARS-CoV-2, with 38% of those infections undiagnosed. Conclusions The estimated prevalence of SARS-CoV-2 infection was 4.6%, and over one-third of infections were undiagnosed. Undiagnosed SARS-CoV-2 infection may pose substantial risk for transmission to other staff and patients.