Intermediate Host of CoV and SARS-CoV-2

Wuhan, a Chinese city, caught the world’s attention after the outbreak of a pandemic caused by the coronavirus 2019-nCoV. Coronaviruses are a group of singlestranded positive-sense RNA that are supposed to cause various diseases in animals, including humans. The four genera of CoVs are αCoV, βCoV, ϒCoV, δCoV.CoVs. Initially, it was thought that the infection caused by these groups of viruses is only limited to their animal host. But now, they are believed to have passed from their animal host to humans and caused disease in humans. The pieces of evidence of this cross between animal-human species barrier have been supported by CoVs like the SARS CoV and MERS CoV, which has caused diseases in humans. 96% homology of the coronavirus isolated from humans matches with beta coronaviruses. The beta coronaviruses are usually found in bats in the genus Rhinolophus. Similarly, 92% homology of the SARS-CoV matches with SARS-like viruses that are found in bats. The majority of the SARS-like viruses are found in the Rhinolophus genus of the bats. This match of homology between COVID-19 virus and beta coronavirus suggests that COVID-19 virus is somehow associated with the Rhinolophus genus in Bats. Bats of this genus are widespread across Asia, the Middle East, Africa, and Europe. These links point out that there must be an intermediate host that could have probably facilitated the transfer of this virus from an animal reservoir to humans (civets were implicated as an intermediate host for SARS-CoV). Thus the similarities between SARS-CoV and the COVID-19 virus are being further investigated, and efforts are being made to identify the intermediate host.

Keywords: Bats, CoV, Intermediate host, SARS CoV.