Abstract
Coronaviruses are positive sense, single-stranded, enveloped, and non-segmented RNA viruses that belong to the Coronaviridae family within the order Nidovirales and suborder Coronavirinae. Two Alphacoronavirus strains: HCoV-229E and HCoV-NL63 and five Betacoronaviruses: HCoV-HKU1, HCoV-OC43, SARS-CoV, MERS-CoV, and SARS-CoV-2 have so far been recognized as Human Coronaviruses (HCoVs). Coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 is currently the greatest concern for humanity. Despite the overflow of research on SARS-CoV-2 and other HCoVs published every week, existing knowledge in this area is insufficient for the complete understanding of the viruses and the diseases caused by them. This review is based on the analysis of 210 published works, and it attempts to cover the basic biology of coronaviruses, including the genetic characteristics, life cycle, and host-pathogen interaction, pathogenesis, the antiviral drugs, and vaccines against HCoVs, especially focusing on SARS-CoV-2. Furthermore, we will briefly discuss the potential link between extracellular vesicles (EVs) and SARS-CoV-2/COVID-19 pathophysiology.
Highlights
The presence of a hairpin-like RNA pseudoknot (PK) structure and a heptanucleotide slippery sequence (UUUAAAC) that precedes the PK structure, is responsible for triggering the frameshifting event [19,20]. Both the replication of genome and the production of the nested set of sg mRNAs are mediated by the nsps, which are encoded in the replicase gene and assembled into the membrane associated viral replication-transcription complex (RTC)
Coronaviruses are a large group of viruses that cause disease in birds and mammals
The pathology of infection can range from mild symptoms ranging from the common cold to death (SARS, MERS)
Summary
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. 10–15% of all COVID-19 cases have been reported to develop severe disease and approximately 5% shows critical illnesses [5]. The genetics of individuals has been attributed to the susceptibility and host response elicited by SARS-CoV-2 as well as the severity of COVID-19 disease [6,7]. Despite the overflow of research on SARS-CoV-2 and other HCoVs published every week, existing knowledge in this area is insufficient for complete understanding of viruses and the disease caused by them. Only the exhaustive studies on the virology of SARS-CoV-2, genetics of host response and pathophysiology can offer the basis for the development and advancement of preventive as well as therapeutic strategies against the disease [10].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
