COVID-19 infection: Origin, transmission, and characteristics of human coronaviruses

Shereen, Muhammad Adnan; Khan, Suliman; Kazmi, Abeer; Bashir, Nadia; Siddique, Rabeea

Animal models play a vital role to uncover the mechanisms of viral pathogenicity from the entrance to the transmission and designing therapeutic strategies. Previously, to examine the replication of SARS-CoV, various animal models were used which showed the symptoms of severe infection [43] . In contrast to SARS-CoV, no MERS-CoV pathogenesis was observed in small animals. Mice are not vulnerable to infection by MERS-coronavirus due to the non-compatibility of the DPP4 receptor [44] . As the entire genome of the 2019-novel coronavirus is more than 80% similar to the previous human SARS-like bat CoV, previously used animal models for SARS-CoV can be utilized to study the infectious pathogenicity of SARS-CoV-2. The human ACE2 cell receptor is recognized by both SARS and Novel coronaviruses. Conclusively, TALEN or CRISPR-mediated genetically modified hamsters or other small animals can be utilized for the study of the pathogenicity of novel coronaviruses. SARS-CoV has been reported to replicate and cause severe disease in Rats (F344), where the sequence analysis revealed a mutation at spike glycoprotein [45] . Thus, it could be another suitable option to develop spike glycoprotein targeting therapeutics against novel coronaviruses. Recently, mice models and clinical isolates were used to develop any therapeutic strategy against SARS-CoV-2 induced COVID-19 [46, 47] . In a similar study, artificial intelligence prediction was used to investigate the inhibitory role of the drug against SARS-CoV-2 [48] . SARS-CoV-2 infected patients were also used to conduct randomized clinical trials [46, 49, 50] . It is now important that the scientists worldwide collaborate the design a suitable model and investigate the in vivo mechanisms associated with pathogenesis of SARS-CoV-2.