In December 2019, coronavirus disease 2019 (COVID-19), a new de novo
infectious disease, was first identified in Wuhan,
China and quickly spread across
China and around the world. The
etiology was a novel
betacoronavirus, the
severe acute respiratory syndrome coronavirus 2 (
SARS-CoV-2) (Lu et al., 2020). On Mar. 11, 2020,
World Health Organization (
WHO) characterized COVID-19 as a global
pandemic. As of Mar. 22, 2020, over 292 000 confirmed COVID-19 cases have been reported globally. To date, COVID-19, with its high infectivity, has killed more people than
severe acute respiratory syndrome (SARS) and
Middle East respiratory syndrome (MERS) combined (Wu and McGoogan, 2020).