LAUSR

To estimate the duration of SARS-CoV-2 RNA shedding, we conducted a multisite study among patients who had nasopharyngeal specimens tested for SARS-CoV-2 RNA via real-time polymerase chain reaction (PCR) assay at Providence St Joseph Health (a 51-hospital healthcare organization based in Renton, Washington), University of Chicago Medicine in Chicago, Illinois, and NorthShore University HealthSystem (a 5-hospital healthcare system based in Evanston, Illinois). All patients with a positive SARS-CoV-2 PCR test between January 22, 2020, and April 23, 2020 who had at least 1 subsequent SARS-CoV-2 PCR test were included in the study. SARS-CoV-2 PCR tests were ordered at the discretion ofmedical providers at each institution.We calculated the percentage of patients with a persistent positive SARS-CoV-2 PCR test result up to 25 days after the first positive test. This study was approved by the institutional review board of each institution.