In the early 2000s, bats infected with Koranians jumped into raccoon dogs and other wild mammals in southwestern China. Some of these animals were sold in markets, where the Coronus re -jumped to humans. The result was the Sars pandemic, which spread to 33 countries and claimed 774 lives. A few months after that, scientists discovered the crown in mammals known as Palm Civets sold in a market in the center of the epidemic.
In a study published on Wednesday, a team of researchers compared Sars’s evolutionary history with that of Covid 17 years later. The researchers analyzed the genomes of the two crowns that caused the pandemics, along with 248 -related Koreans in bats and other mammals.
Jonathan Pekar, an evolutionary Iologos at the University of Edinburgh and the author of the new study, said the stories of the two crowns followed parallel paths. “In my mind. It’s extremely similar,” he said.
In both cases, Dr. Pekar and his colleagues argue that a crown jumped from bats into wild mammals in southwestern China. In a short period of time, wildlife traders took the infected animals hundreds of miles to the city’s markets and the virus destroyed the devastation to humans.
“When you sell wild animals in the heart of cities, you will have a pandemic every so often,” said Michael Woroby, an evolutionary biologist at the University of Arizona and author of the new study.
The study lands in a full political moment. Last month, the White House created a website entitled “Lab in Beer: The True Origin of Covid 19”, arguing that the pandemic had not been caused by a market market but by an accident in a laboratory in Wuhan, China.
On Friday, in its proposed budget, the White House described the laboratory’s leak as “confirmed” and justified a cut of $ 18 billion at the National Institutes of Health in part in what it described as “inability of the organization to prove that it was not to prove that it was not to prove that it
The Chinese government responded with a flat refusal that Covid had been caused by a Wuhan laboratory leak and raised the possibility that the virus had instead come from a Laboratory of a Judgment in the United States.
“In -depth and in -depth research on the origin of the virus in the US should be conducted,” the statement said.
Sergei Pond, a Iologist at Temple University, said he did not consider the origin of Covid. But he was worried that the incendiary language from the two governments would make it difficult for scientists to explore – and discuss – the origin of Covid.
“If it weren’t tragic, you should be laughing. It’s so long,” Dr. Pond said.
In the first weeks of the Covid pandemic in early 2020, allegations were released that the responsible virus, Sars-COV-2, was a biological weapon created by the Chinese army. A team of scientists who analyzed the available data then rejected this idea. Although they could not exclude a random laboratory leak, they favored a natural origin of Covid.
Over time, Dr. Woroby, who was not a member of this group, became disappointed that there was not enough evidence yet to choose a theory over the other. An open letter was signed with 17 other scientists demanding more research to determine which explanation was most likely.
“For us it seemed that there was a lot we don’t know, so let’s not reject the idea of the workshop,” Dr. Woroby said. “Let’s study it.”
As Dr. Worobey and other scientists began to study the origin of Covid, the US intelligence services also evaluated it. Their ratings have been mixed. The FBI and the CIA favor a escape from the Wuhan Institute of Iology, though with low certainty. The Ministry of Energy is leaning with low confidence in the virus that escapes a different Wuhan laboratory. Other organisms lean towards a natural origin.
Organizations have not made their evidence or analyzes publicly, so scientists cannot evaluate the basis of their conclusions. However, Dr. Worobey and other researchers published a series of documents in scientific journals. Along the road, Dr. Woroby was convinced that the Covid pandemic had begun at the Huanan seafood market in Wuhan.
“Scientifically, it is as clear as HIV or the Spanish flu,” said Dr. Worobey, referring to two diseases whose origin has also studied.
For the new study, Dr. Woroby, Dr. Pekar and their colleagues compared the genomes of the 250 Coras, using their genetic similarities and differences in identifying their relationships. They were able to reconstruct the story of the carnivores that cause both Sars and Covid-known as Sars-Cov and Sars-COV-2.
The ancestors of both cronies have been released in bats in much of China and neighboring countries for hundreds of thousands of years. In the last 50 years, their immediate ancestors have been infecting bats that lived in southwest China and northern Laos.
As the coronies were infected with the bats, they sometimes ended up in a cell with another Korana. When the cell made new viruses, it created random hybrids that had genetic material from both original Coranians – a process known as recombinant.
“These are not ancient events,” said David Rasmussen, a Iologist at the North Carolina State University, who did not participate in the new study. “These things are happening all the time. These viruses are really mosaic.”
In 2001, just a year before the Sars pandemic in Guangzhou began, the researchers who found, Sars-Cov underwent a last genetic mixing of bats. Only after this latter recombination could the virus evolve into a human pathogen. And since Guangzhou is several hundred miles from the Sars-Cov ancestral area, bats could not bring the virus to the city in such a short time.
Instead, the researchers generally agree, the ancestors of Sars-Cov contaminated wild mammals who were later sold in purchases around Guangzhou. A few months after the start of the SARS pandemic, the researchers discovered Sars-Cov in Palm Civets and other wild mammals for sale in the markets.
The researchers found a similar pattern when they turned to Sars-COV-2, the cause of Covid. The last recombinant in bats took place between 2012 and 2014, just five to seven years before the Covid pandemic, several hundred miles northeast, Wuhan.
This was also a significant divergence from the area where the ancestors of the virus had been released. But it was comparable to the journey that Sars-Cov took, with the courtesy of wildlife trade.
Supporters of laboratory theories have highlighted the great distance between Wuhan and the positions where Sars-COV-2’s closest relatives were found. If the bats were unable to fly around the wuhan and infect wild mammals there, they maintain, then scientists must have collected the Corana from bats in southwestern China and pass it on to their workshop, from which they then escape.
US scientists have criticized Wuhan’s Iology Institute for loose safeguards in Koronai’s experiments. But no one has offered evidence that the ancestors of Sars-COV-2 was at the Wuhan Institute of Iology before the pandemic. The new study of Dr. Worobey and his colleagues shows that the bat’s crown can travel long distances without the help of scientists, through wildlife trade.
Researchers argue that these findings agree with studies published in 2022, showing the Huanan seafood market in Wuhan as the place where Covid’s pandemic began. Wild mammals were sold there. Many early cases of Covid were recorded there and Chinese researchers gathered different SARS-COV-2 executives carrying distinct mutations there. Dr. Worobey and his colleagues claimed that the virus had been spilled twice by wild mammals on the market.
Dr. Pond said the new study was in line with the theory of a rejection of wild animals. But he does not think that the matter was settled. He noted that last year two statisticians questioned the model behind the study of 2022. Dr. Woroby and a colleague have faced this criticism. “This discussion is still ongoing,” Dr. Pond said.
Marc Eloit, former director of the Discovery Pathogen Laboratory at the Pasteur Institute in Paris, said the new study was important to provide a clear picture of where Sars-COV-2 came.
But he also observed that Koronas was significantly different from his closest known relatives in bats. After being separated from these viruses, it must have been mutated or subjected to recombinant to become well adapted to spread to humans.
“I argue that the likelihood of a recombinant event – whether accidental or deliberate – in a laboratory environment remains just as reasonable as the case of appearance through an intermediate host on the market,” said Dr. Eloit.
Dr. Eloit and other scientists have agreed that finding an intermediate form of Sars-COV-2 in a wild mammal would make an urgent case of a natural leak. The Chinese authorities examined some animals at the beginning of the pandemic and did not find the virus in them.
However, wildlife sellers in the Huanan market removed their animals from the benches before scientists could study them. And when China put a stop in sales of wild animals, the farmers dug their animals.
“There is a big piece that is missing, and you really can’t dance around it,” said Dr. Pond.
Stephen Goldstein, a geneticist of the University of Utah, who did not participate in the new study, said the research served as a warning of the risk of a future Koranian pandemic. Wild mammals sold in markets anywhere in the area where Sars and Covid started could become a vehicle in a city hundreds of miles away. “The pieces of these viruses exist in all these places,” said Dr. Goldstein.
