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Low Utility of Repeat Real-Time PCR Testing for SARS-CoV-2 in Clinical Specimens


      In a multicenter cohort of 22,315 patients tested for COVID-19, 1676 (7.5%) had repeat testing via real-time polymerase chain reaction following an initial negative test. Of those retested within 7 days of their first negative test, only 2.0% had a positive result. This suggests that repeat testing from the same source is unlikely to provide additional information.

      Abbreviations and Acronyms:

      COVID-19 (coronavirus disease 2019), IQR (interquartile range), RT-PCR (reverse transcriptase polymerase chain reaction), SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2)
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      Linked Article

      • In Reply—Repeated Testing in SARS-CoV-2 Infection
        Mayo Clinic ProceedingsVol. 95Issue 10
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          We appreciate the points raised by Lippi et al regarding our article describing repeated testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.1 In summary, the authors emphasize that repeated testing may be helpful in improving the negative predictive value of testing and ensuring that cases of COVID-19 are identified. The authors include evidence supporting the conclusion that identification of the SARS-CoV-2 virus is directly related to the number of nasopharyngeal swabs that are collected and also emphasize the importance of case-finding in control of the pandemic.
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      • Repeated Testing in SARS-CoV-2 Infection
        Mayo Clinic ProceedingsVol. 95Issue 10
        • Preview
          In a recently published article in the journal, Challener et al1 showed that 2.0% of participants (ie, 22 of 1113) tested positive within 1 week of the first negative nasopharyngeal swab for identification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. This evidence persuaded the authors to conclude that repeating an identical test in a low-prevalence environment is unlikely to generate added clinical value. However, some important considerations would lead us to disagree with this conclusion.
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