A comparative study on virology, epidemiology, and clinical features of SARS and COVID-19.

In December 2019, an outbreak of an unknown cause of pneumonia [later named coronavirus disease 2019 (COVID-19)] occurred in Wuhan, China. This was found to be attributed to a novel coronavirus of zoonotic origin, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2; previously named 2019 novel coronavirus or 2019-nCoV). The SARS-CoV-2, a new type of highly pathogenic human coronavirus related to severe acute respiratory syndrome coronavirus (SARS-CoV), spread rapidly worldwide and caused 53,164,803 confirmed infections, including 1,300,576 deaths, by November 13, 2020 (globally, 206,196,367 cases and 4,345,424 deaths as of August 13, 2021). SARS-CoV-2 and SARS-CoV vary in their specific characteristics, regarding epidemics and pathogenesis. This article focuses on the comparison of the virology, epidemiology, and clinical features of SARS-CoV and SARS-CoV-2 to reveal their common and distinct properties, to provide an up-to-date resource for the development of advanced systems and strategies to monitor and control future epidemics of highly pathogenic human coronaviruses.