Three years after the start of the pandemic by COVID-1 It has not yet been possible to determine the exact origin of the coronavirus SARS-CoV-2, despite various theories that pointed to everything from bats to stray dogs to a possible leak in a laboratory. But new scientific evidence suggests that a infected raccoon dog could have been the origen animal from COVID that has killed millions of people.
An international team of scientists has reached this preliminary conclusion after analyzing genetic sequences from the Wuhan market, and while this is not definitive proof and needs to be reviewed by other scientists, it is the stronger evidence on the animal origin of the pandemic that has been found up to now and once again points out as the most probable cause that a transmission of coronavirus to humans through infected animalsinstead of an accidental leak of the virus from a Wuhan laboratory, as the latest report from the United States suggested three weeks ago.
The new report has been carried out by a team made up of virologists, experts in genomics and evolutionary biologists who have analyzed genetic sequences of samples taken from market animals from this Chinese city and have identified SARS-CoV-2 in a tanuki, a raccoon dog or Japanese raccoon that was sold illegally at the end of 2019. The virologist Angela Rasmussen who has participated in this investigation has affirmed in statements to The Atlantic that “this is a strong indication that the animals in the market were infected. There is no other explanation that makes sense.”
It is the first time that this genetic material has been made available to scientists outside of China, thanks to researchers from the Chinese CDC sharing the data on the GISAID open web, and although the information has subsequently been withdrawn, several international groups had already accessed it. them and had downloaded them. The Chinese researchers presented their results in February 2022, but at the time they thought that animals that had tested positive for the virus could have been infected by humans.
SARS-CoV-2 coronavirus family tree
The results of the new research – which have not yet been published in any scientific journal, although they were presented to the WHO on March 14 – reveal that several samples positive for SARS-CoV-2 are associated with a history of animal genetic material. . Researchers, including Edward Holmes, who is one of the experts who has played a key role in the fight against COVID, have designed a family tree of the coronavirus whose most probable origin goes back to the raccoon dog, a mammal that is bred for sale in China and would have the ability to infect people with this type of virus.
The findings do not constitute conclusive proof that the origin of the pandemic lies in the transmission of the virus to humans through this animal, since the route of transmission could have been another animal, and even a person infected with SARS- CoV-2 could have passed the virus to the raccoon dog.
However, as reported The New York Timesthe analysis has determined that the raccoons have deposited genetic signatures in the same place where the genetic material of the virus was left: a scenario in which the virus was transmitted to humans by a wild animal because many of the first cases of COVID were detected workers, customers or people residing near the Wuhan market.