COVID-19 Admission Screening, and Assessment of Infectiousness at an Academic Medical Center, Iowa 2020
Abstract Objective: Patients admitted to the hospital may unknowingly carry SARS-CoV-2 and hospitals have implemented SARS-CoV-2 admission screening. However, because SARS-CoV-2 RT-PCR may remain positive for months after infection, positive results may represent active or past infection. We determined the prevalence and infectiousness of patients who were admitted for reasons unrelated to COVID-19 but tested positive on admission screening. Methods: We conducted an observational study at the University of Iowa Hospitals & Clinics from July 7 to October 25, 2020. All patients admitted without suspicion of COVID-19 infection were included and medical records of those with a positive admission screening test were reviewed. Infectiousness was determined using patient history, PCR cycle threshold (Ct) value, and serology. Results: A total of 5,913 patients were screened and admitted for reasons unrelated to COVID-19. Of these, 101 had positive admission RT-PCR results. Thirty-six patient were excluded because they had respiratory signs/symptoms on admission on chart review. Sixty-five patients (1.1%) did not have respiratory symptoms. A total of 55 patients had Ct values available and were included in this analysis. The median age was 56 years, and (51%) were male. Our assessment revealed that 23 patients (42%) were likely infectious. The median duration of in-hospital isolation was five days for those likely infectious and two days for those deemed non-infectious. Conclusions: COVID-19 infection was infrequent among patients admitted for reasons unrelated to COVID-19. An assessment of the likelihood of infectiousness using clinical history, RT-PCR Ct values, and serology may help discontinue isolation and conserve resources.