Progression/remission of COVID-19: data-driven recommendations for repeating SARS-CoV-2 nucleic acid amplification tests.

Williams, Nathan; Idriss, Reed; Dodge, Jessica; Barasch, Samuel

AIMS This short study was performed to better understand the time frame associated with changes in SARS-CoV-2 nucleic acid testing and provide recommendations for repeat testing. Recommendations are useful as little guidance is available for repeat testing in patients being followed expectantly for changes in disease. METHODS A review of laboratory data of tests for SARS-CoV-2 nucleic acid was performed selecting patients who had changing results. Time between changes in test results was determined to provide guidance for repeat testing. RESULTS The Interquartile Range (IQR) of data for patients who had a negative to positive change in laboratory testing (progression) was 6-16 days (median=9 days). The IQR of data for patients who had a positive to negative change in test results (remission) was 9-21 days (median=14 days). CONCLUSION Because sampling of the nares or nasopharynx can be variable, repeat testing should be performed swiftly when symptomatic patients are negative. The data in this short study vary widely, so authors recommend repeat testing during a period of time associated with the IQR or median (see results above).