is worth mentioning that SARS-COV, which was widespread in 2002 caused more than 8000 cases and about 800 deaths and MERS-COV in 2012 also spread in more than 25 countries, causing about 2500 cases and more than 850 deaths. (www.who.int/health-topics/coronavirus).5
In all coronaviruses, a homotrimeric spike glycoprotein on the virion’s envelope mediates coronavirus entry into host cells through a mechani