One‐step and sequential SARSCOV‐2 polymerase chain reaction tests would not work every time

IntroductionRT‐PCR is widely used as a diagnostic test for the detection of SARS‐CoV‐2. In this study, we aim to describe the clinical utility of serial PCR testing in the final detection of COVID‐19.MethodWe collected multiple nasopharyngeal swab samples from patients who had negative RT‐PCR test on the first day after hospitalization. RT‐PCR tests were performed on the second day for all patients with initial negative result. For the patients with secondary negative results on day 2, tertiary RT‐PCR tests were performed on day 3 after hospitalization.ResultAmong 68 patients with initial negative test results, at the end of follow‐up, the mortality number was 20 (29.4%). About 33.8% of patients had subsequent positive PCR test results for the second time and 17.4% of the patients who performed third PCR test had positive result.ConclusionBased on this study, serial RT‐PCR testing is unlikely to yield additional information.