What is SARS-CoV-2?

There is currently a widespread infection with SARS-CoV-2, and 9,045,604 coronavirus cases have been reported in 213 countries and territories around the world, with 470,698 deaths, as of 02:38 GMT on June 22. Now that a pandemic has occurred, it is critical to learn some basic information about this previously unknown coronavirus, SARS-CoV-2.

World map indicating countries reporting COVID-19 cases, as of 12:00 p.m. ET June 19, 2020 (CDC, 2020)

The acronym SARS-CoV-2 stands for the severe acute respiratory syndrome coronavirus 2 that causes coronavirus disease 2019 (COVID-19). It is a member in Coronaviridae family, a diverse family of single-stranded RNA viruses. Just like other coronaviruses in the family, SARS-CoV-2 looks like a beautiful crown under the electron microscope, thanks to the surface glycoproteins that decorate the virus. 

The image of SARS-CoV-2 (CDC, 2020)
Though with a harmless appearance, SARS-CoV-2 is no doubt a tough and remorseless killer. As the successor to SARS-CoV-1, a human coronavirus that caused SARS in 2003, SARS-CoV-2 has the similar stability as SARS-CoV-1 under the experimental circumstances, and its infectious ability can be remained in aerosols for hours and on surfaces up to days. Once it infects an individual, its genome produces proteins that delay human body immune system from sounding an alarm. Then, it sneaks into the lung, uses the cell's machinery to help make copies of itself and kills the infected cell, commonly causing illnesses ranging from mild to serious illness (cough and shortness of breath) and even death.

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