How did the coronavirus start and where did it come from? Was it really the Wuhan Animal Market? | News from the world

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In the minds of the public, the story of the origin of the coronavirus seems well established: at the end of 2019, someone at the now famous seafood market of Huanan in Wuhan was infected with a virus from an animal.

The rest is part of a horrible story still in the making, Covid-19 extending from this first cluster in the capital of Hubei province in China to a pandemic that has killed around 80,000 people so far.

Archival footage of pangolins – a scaly mammal that looks like an anteater – has reached news reports, suggesting that this animal was the relay of the virus before it spread to humans.

But there is uncertainty about several aspects of the history of the origin of Covid-19 that scientists are working to unravel, including the species that have transmitted it to humans. They’re trying hard because knowing how a pandemic starts is key to stopping the next one.

Professor Stephen Turner, head of the microbiology department at Monash University in Melbourne, says the most likely is that the virus comes from bats.

But that’s where his certainty ends, he says.

Assuming that the virus emerged in the Wuhan live animal market from an interaction between an animal and a human, Turner said, “I don’t think it’s conclusive in any way. “

“Part of the problem is that the information is only as good as the surveillance,” he said, adding that viruses of this type circulate all the time in the animal kingdom.

The fact that the virus infected a tiger in a New York zoo shows how viruses can move between species, he says. “It is important to understand the extent of the species that this virus can infect because it helps us to pinpoint where it might have come from.”

Scientists say it is very likely that the virus originated from bats, but first crossed an intermediate animal in the same way as another coronavirus – the Sars epidemic in 2002 – has passed horseshoe bats to civets looking like cats before infecting humans.





A pangolin

Pangolins are “the best selling illegal mammal in the world”. Photography: Themba Hadebe / AP

One animal involved as an intermediate host between bats and humans is the pangolin. The International Union for Conservation of Nature claims that they are “the most illegally traded mammal in the world” and are valued for their meat and the claimed medicinal properties of their scales.

As noted in Nature, pangolins were not listed in the inventory of items sold in Wuhan, although this omission may be deliberate as it is illegal to sell them.

“Whether poor pangolin was the species he jumped at is unclear,” said Turner. “It is mixed with something else, mixed with a poor pangolin, or it jumped in people and evolved in people. “

Professor Edward Holmes of the University of Sydney was the co-author of a nature study that examined the likely origins of the virus by examining its genome. On social media, he stressed that the identity of the species that served as an intermediate host for the virus is “still uncertain“.

A statistical study examined a characteristic of the virus that has evolved to allow it to cling to human cells. Pangolins were able to develop this characteristic, just like cats, buffaloes, cattle, goats, sheep and pigeons.



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