In late 2019, a novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was identified as the cause of a familial cluster of pneumonia in the Hubei Province of China.1 Human-to-human transmission was identified, and it spread worldwide with cases in the United States first identified in January 2020.2 On March 11, 2020, the World Health Organization declared coronavirus disease 2019 (COVID-19), the disease caused by SARS-CoV-2, a worldwide pandemic.3 As of August 1, 2020, the virus has killed more than 675,060 people worldwide with more than 20% of those recorded deaths within the United States.4

SARS-CoV-2 is a positive-strand RNA virus belonging to the Betacoronavirus that also contains severe acute respiratory syndrome coronavirus (SARS-CoV) (virus cause of SARS) and Middle East respiratory syndrome coronavirus (MERS-CoV).5 The virus uses its structural spike (S) protein to attack the target cells and binds to the host angiotensin-converting enzyme 2 protein. It is primed by the host transmembrane protease, serine 2 encoded by TMPRSS2 gene, to enter the cell using the host cell endosomes.6 Viral polyproteins are then synthesized and encode for the replicase-transcriptase complex. RNA is synthesized via its RNA-dependent RNA polymerases. Proteins are then synthesized together leading to completion of assembly and release of viral particles.

Reference link-