COVID, March 14: According to a new study, Scientists progenitor of the novel coronavirus underwent “very little change” to adapt to humans from bats which suggest that the ability of the virus to spread from one person to another likely evolved in the flying mammal prior to it jumping to its new human host.
The study was published in the journal PLOS Biology, assessed hundreds of thousands of sequenced genomes of the SARS-CoV-2 virus. This study found that for the first 11 months of the COVID-19 pandemic, there has been very little ‘important genetic change‘ observed in the coronavirus.
However, it noted that some changes such as the D614G mutation and similar tweaks in the virus spike protein has affected its biology.
“This does not mean no changes have occurred, mutations of no evolutionary significance accumulate and ‘surf’ along the millions of transmission events, as they do in all viruses,” explained study first author Oscar MacLean from the University of Glasgow Centre for Virus Research in Scotland.
But the scientists said it was “surprising” how transmissible Coronavirus has been from the outset.
“Usually viruses that jump to a new host species take some time to acquire adaptations to be as capable as SARS-CoV-2 at spreading, and most never make it past that stage, resulting in dead-end spillovers or localized outbreaks,” said Sergei Pond, another co-author of the study.
Analyzing the mutations undergone by the novel coronavirus and related arboviruses — the group of viruses the COVID virus belongs to from bats and pangolins — the scientists found evidence of fairly a significant change, but all before the emergence of SARS-CoV-2 in humans.
Based on this observation, the researchers said SARS-CoV-2 came with a ready-made ability to infect humans and other mammals, with these properties likely evolving in bats prior to it jumping to humans.
“While an undiscovered ‘facilitating’ intermediate species cannot be discounted, collectively, our results support the progenitor of SARS-CoV-2 being capable of efficient human–human transmission as a consequence of its adaptive evolutionary history in bats, not humans, which created a relative generalist virus,” the scientists wrote in the study.