May 8, 2020

Occurrence and Timing of Subsequent SARS-CoV-2 RT-PCR Positivity Among Initially Negative Patients

Category: Article Summary

Topic: Testing and Treatment

• Two independent research teams from the University of Washington (UW) and Stanford Health Care reported a similar frequency of discordant SARS-CoV-2 RT-PCR results among initially negative patients subjected to repeat testing. Among 626 patients who were initially test-negative and re-tested within 7 days, repeat testing yielded a positive result in 3.5% of cases (4.3% UW, 2.8% Stanford). The majority (96.5%) of patients with an initial negative result who warranted re-evaluation remained negative on subsequent tests performed within this window.  
• These observations suggest that false negative results at the time of initial presentation do occur, but potentially at a lower frequency than what is currently believed.  

Long et al. (May 8, 2020). Occurrence and Timing of Subsequent SARS-CoV-2 RT-PCR Positivity Among Initially Negative Patients. Pre-print downloaded May 8 from https://doi.org/10.1101/2020.05.03.20089151