Shanghai: The virus that causes COVID-19 may have started spreading in China as early as October 2019, two months before the first case was reported in the central city of Wuhan, a new study showed on Friday.
UK researchers University of Kanto used conservation science methods to estimate that SARS-CoV-2 first appeared from early October to mid-November 2019, according to a paper published in Without this Pathological magazine.
They estimated that the most likely date for the virus to emerge was November 17, 2019, and that it had probably spread globally by January 2020.
China’s first official COVID-19 case was in December 2019 and was linked to the Huanan seafood market in Wuhan.
However, some of the early cases had no known association with Huanan, meaning that SARS-CoV-2 was circulating before it even hit the market.
A joint study published by China and World Health Organization acknowledged in late March that there may have been sporadic human infections before the Wuhan outbreak.
In a paper released in preprint form this week, Jesse Bloom of the Fred Hutchinson Cancer Research Center Seattle Recovered deleted sequencing data from early COVID-19 cases in China.
The data showed that samples taken from the Huanan market were “not representative” of SARS-CoV-2 as a whole, and were a variant of a previously transmitted ancestral sequence that had spread to other parts of China.
The US National Institutes of Health confirmed to Reuters that the samples used in the study were submitted to the Sequence Read Archive (SRA) in March 2020 and were later removed at the request of Chinese investigators, who said they were updated. and deposited in another collection. .
Critics said the deletion was further evidence that China was trying to cover up the origins of COVID-19.
“Why would scientists ask international databases to remove key data that informs us about how COVID-19 started in Wuhan?” Harvard Broad Institute researcher Alina Chan wrote on Twitter.
Another study by Australian scientists, published Thursday in the journal Scientific Reports, used genomic data to show that SARS-CoV-2 binds to human receptors far more readily than other species, suggesting that It was already adapted to humans when it first emerged.
It said it is possible that another unknown animal with an even stronger affinity may have served as an intermediary species, but the hypothesis that it leaked from the laboratory could not be ruled out.
“Although it is clear that early viruses had a high propensity for human receptors, this did not mean that they were ‘man-made’,” said Dominic Dwyer, an infectious disease specialist at Westmead Hospital in Australia. 19 in Wuhan this year.
“Such conclusions remain speculative,” he said.
Serum samples still need to be tested to make a strong case about the origin of COVID-19, said Stuart Turville, associate professor at the Kirby Institute, an Australian medical research organization that responds to the University of Kent study. were giving.
“Unfortunately, with the current pressure of the laboratory leak hypothesis and the sensitivity in carrying out this follow-up research in China, it may take some time for us to see such reports,” he said.
UK researchers University of Kanto used conservation science methods to estimate that SARS-CoV-2 first appeared from early October to mid-November 2019, according to a paper published in Without this Pathological magazine.
They estimated that the most likely date for the virus to emerge was November 17, 2019, and that it had probably spread globally by January 2020.
China’s first official COVID-19 case was in December 2019 and was linked to the Huanan seafood market in Wuhan.
However, some of the early cases had no known association with Huanan, meaning that SARS-CoV-2 was circulating before it even hit the market.
A joint study published by China and World Health Organization acknowledged in late March that there may have been sporadic human infections before the Wuhan outbreak.
In a paper released in preprint form this week, Jesse Bloom of the Fred Hutchinson Cancer Research Center Seattle Recovered deleted sequencing data from early COVID-19 cases in China.
The data showed that samples taken from the Huanan market were “not representative” of SARS-CoV-2 as a whole, and were a variant of a previously transmitted ancestral sequence that had spread to other parts of China.
The US National Institutes of Health confirmed to Reuters that the samples used in the study were submitted to the Sequence Read Archive (SRA) in March 2020 and were later removed at the request of Chinese investigators, who said they were updated. and deposited in another collection. .
Critics said the deletion was further evidence that China was trying to cover up the origins of COVID-19.
“Why would scientists ask international databases to remove key data that informs us about how COVID-19 started in Wuhan?” Harvard Broad Institute researcher Alina Chan wrote on Twitter.
Another study by Australian scientists, published Thursday in the journal Scientific Reports, used genomic data to show that SARS-CoV-2 binds to human receptors far more readily than other species, suggesting that It was already adapted to humans when it first emerged.
It said it is possible that another unknown animal with an even stronger affinity may have served as an intermediary species, but the hypothesis that it leaked from the laboratory could not be ruled out.
“Although it is clear that early viruses had a high propensity for human receptors, this did not mean that they were ‘man-made’,” said Dominic Dwyer, an infectious disease specialist at Westmead Hospital in Australia. 19 in Wuhan this year.
“Such conclusions remain speculative,” he said.
Serum samples still need to be tested to make a strong case about the origin of COVID-19, said Stuart Turville, associate professor at the Kirby Institute, an Australian medical research organization that responds to the University of Kent study. were giving.
“Unfortunately, with the current pressure of the laboratory leak hypothesis and the sensitivity in carrying out this follow-up research in China, it may take some time for us to see such reports,” he said.
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