corona virus-Covid19

False Negative COVID-19 Tests Relatively Common During Recovery Interview with:

corona virus-Covid19Dr. Francesco Venturelli
Servizio di Epidemiologia
Direzione Sanitaria – Azienda USL-IRCCS di Reggio Emilia
Padiglione Ziccardi, Via Amendola What is the background for this study?

Response: Contact tracing and isolation for people testing positive for SARS-CoV-2 are two of the main strategies to limit the viral spread and contain the current pandemic. Long persistence of viral RNA detected by RT-PCR on nasopharyngeal swabs is commonly reported, while its correlation to virus viability is still debated. What are the main findings? 

Response: The study showed that in people with COVID-19, the median time between symptoms onset and viral clearance at RT-PCR was 36 days. Moreover, an overall 20% risk of “false negative” results at RT-PCR was observed, decreasing with time from diagnosis. What should readers take away from your report?

Response: In countries in which the testing strategy for the follow-up of people with COVID-19 require at least one negative test to end isolation, this evidence support the assessment of the most efficient and safe retesting timing: i.e. 30 days after disease onset. What recommendations do you have for future research as a result of this work?

Response: The results of this study clearly highlight the importance of producing evidence on the duration of SARS-CoV-2 infectivity to avoid unnecessary isolation without increasing the risk of viral spread from clinically recovered people. Is there anything else you would like to add? The research activity on SARS-CoV-2 infection and COVID-19 of the Azienda USL-IRCCS of Reggio Emilia, Italy, continue in many different fields to actively contribute to this international unprecedented challenge.

No disclosures.



Mancuso PVenturelli FVicentini M, et al
Temporal profile and determinants of viral shedding and of viral clearance confirmation on nasopharyngeal swabs from SARS-CoV-2-positive subjects: a population-based prospective cohort study in Reggio Emilia, Italy.

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Last Updated on September 3, 2020 by Marie Benz MD FAAD