Australian Study: COVID-19 'Exquisitely Adapted' for Human Cells

A major new Australian study of COVID-19 has found that it seems specially adapted to infect human cells, casting some doubt on whether it emerged in bats or pangolins when it first erupted in China.

As a consequence, the scientists behind the study say, a “possibility which still cannot be excluded is that SARSCoV-2 was created by a recombination event that occurred inadvertently or consciously in a laboratory handling coronaviruses, with the new virus then accidentally released into the local human population"

The high-performance computer modeling was used by Australian scientists to study the virus's ability to target a variety of 12 exotic and domestic animals in the hope of identifying the original source of the virus.

The goal is to find a vaccine or drug treatment for the highly infectious COVID-19.

Led by scientists at Flinders University, looked at the the virus's ability to bind to human cells and found the SARS-CoV-2 virus targets humans more potently than any of the tested animal species.

"The results clearly show that the COVID-19 virus is exquisitely adapted to infect humans," says Flinders University Professor Nikolai Petrovsky, lead author of a new paper just published online in arXiv, a leading US preprint server for researchers.

"The virus's ability to bind protein on human cells was far greater than its ability to bind the same protein in bats, which argues against bats being a direct source of the human virus."

The study cast doubt on the idea that it emerged with pangolins, an ant-eater very popular with some Chinese cooks.

"While it has been suggested by some Chinese scientists that the COVID-19 virus might have been transmitted to humans from pangolins, currently available data does not support this idea," Professor Petrovsky says.

But how COVID-19 so quickly became lethal to humans remains a mystery.

The research points to a number of reasons why the virus became so well adapted to humans, such as convergent evolution after exposure to human cells, rare mutations that mix two species genes, and exposure to human cells very early in the pandemic.

The article, 'In silico comparison of spike protein-ACE2 binding affinities across species; significance for the possible origin of the SARS-CoV-2 virus' (2020) has been published on the arXiv pre-press server.