Introduction
Since December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-Coronavirus-2 (SARS-CoV-2)), which causes coronavirus disease 2019 (COVID-19) has been the focus of global attention. This severe respiratory illness originated in Wuhan City in the Hubei province in China and is capable of rapid community transmission. Thus far, the most efficient effort at limiting disease spread has been by minimizing person-to-person contact and by isolating infected patients1. The clinical spectrum of COVID-19 includes asymptomatic infection, mild upper respiratory tract illness, severe viral pneumonia with respiratory failure, and death2.
In previous studies of seasonal influenza, it has been shown that the longer duration of viral RNA shedding (among other factors such as the use of corticosteroids, the delay of antiviral treatment, and other comorbidities) is correlated with worse patient prognosis3). Furthermore, our previous studies have revealed that viral RNA clearance is associated with prognosis in patients infected with influenza A(H7N9)4.
Although observational studies have shown that viral RNA concentration is independently associated with risk of complications and respiratory insufficiency in influenza 3-6, it has yet to be determined if a longer duration of viral RNA shedding in SARS-CoV-2 is also associated with worse patient prognosis and disease progression (including severe viral pneumonia with respiratory failure and/or death). Additionally, a previous study reported that the median duration of viral shedding in patients who recovered from COVID-19 was 20 days, although this study did not test if there was an association of viral shedding with patient recovery2. In this retrospective study, we explore the correlation between the viral RNA shedding duration of SARS-CoV-2 and patient prognosis to determine if viral shedding duration time could be used to assess patient risk of transmission and to help guide clinical decisions for patients infected with COVID-19.