Three different strains of CoV (Coronavirus) have crossed the species obstruction to cause fatal pneumonia in humans since the start of the 21st century: SARS-CoV (severe acute respiratory syndrome) (Drosten et al., 2003), MERS-CoV (Middle-East respiratory syndrome) (Zaki et al., 2012) and SARS-CoV-2 (causative agent of COVID-19) (Huang et al., 2020), first emerged in the Wuhan city, December 2019, in the province of Hubei, China, was isolated and sequenced in January 2020. An ongoing eruption of COVID-19 (atypical pneumonia) has affected more than 36, 471, 856 individuals and claimed 1,061,788 lives in 213 countries as of October 8, 2020. It became a super- hot spreading virus, such that the World health organization declared it as a Public Health emergency of International concern on January 30, 2020 (Zhou et al., 2020). MERS-CoV virus was reported to be originated from bats, where camels acted as a reservoir host (Haagmans et al., 2014). SARS-CoV and SARS-CoV-2 are genetically closely related and believed to be originated from bats, whose intermediate reservoir host is unknown. The persistent spillovers of CoVs in humans besides the recognition of numerous coronavirus strains in bats, including SARS-CoVs, imply the future continues zoonotic transmission events (Anthony et al., 2017; Ge et al., 2013; Zhou et al., 2020). In addition to an extremely pathogenic strains of CoV; MERS-CoV, SARS-CoV and SARS-CoV-2, belonging to same genus (b-coronavirus), four other low-pathogenic endemic strains in humans are also reported: HCoV-229E, HCoVHKU1, HCoV-NL63 and HCoV-OC43.Till date, no vaccines or therapeutics are available against any human infecting strain of CoVs.