“No evidence” to support former CDC director’s theory that coronavirus escaped from lab, scientists say

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Dr Robert Redfield, former director of the Centers for Disease Control and Prevention, told CNN he believed the coronavirus originally escaped from a laboratory in Wuhan, China. But a team of experts from World Health OrganizationDr Anthony Fauci and a number of virological experts have said the evidence to support such a claim is simply not there.
“I do not believe that this has come of a bat to a human. And at that point the virus came to humans, became one of the most infectious viruses we know of in humanity for human-to-human transmission, ”Redfield told Dr. Sanjay Gupta from CNN in a taped interview in January. “Normally, when a pathogen moves from a zoonot to humans, it takes a while to figure out how to become more and more effective. ”

Redfield, a virologist who ran the CDC under President Trump, has repeatedly stressed that this is only his opinion and not a fact. “I’m allowed to have opinions now,” he said. According to Redfield, the extremely rapid transmission of the new coronavirus, in his opinion, indicates that it was probably grown in a laboratory for this specific purpose. “Most of us in a lab, when we’re trying to grow a virus, we’re trying to make it grow better and better, better and better, better, better, and better so that we can experiment. and understand. the way I put it together, ”he said of his theory.

Redfield, however, also said he believed the virus had started to spread months earlier than previously thought – possibly since September or October 2019, a period roughly backed up by recent research. This extra time that the virus may have spent circulating undetected could help explain how it became “effective” in transmission – without having been “disclosed” from a lab.

Dr Anthony Fauci responded to Redfield’s comments during Friday’s COVID-19 response briefing and suggested that most public health officials disagree. He noted that if the virus had escaped from a laboratory, it would mean that “it was essentially entering the outside human population already well adapted to humans.”

“However, the alternative explanation that most public health professionals use is that this virus did circulate in China, possibly Wuhan, for a month or more before being clinically recognized at the end of the month. of December 2019, ”Fauci said.

“If that were the case, the virus could clearly have adapted to a greater efficiency of transmissibility during this period of time, up to and at the time it was recognized. So, Dr Redfield mentioned that he was giving an opinion as a possibility, but again, there are other alternatives – others that most people hold onto. ”

Understanding when the coronavirus first appeared is an important piece of the epidemiological puzzle, one that scientists around the world WHO team, worked to nail. A study, recently published in the journal Science, found that “the period between mid-October and mid-November 2019” was “the plausible interval when the first case of SARS-CoV-2 appeared in the province of Hubei ”.

“It is very likely that SARS-CoV-2 was circulating in Hubei province at low levels in early November 2019 and possibly as early as October 2019, but not earlier,” the study reads. But for weeks or months, its prevalence was low enough to escape attention. “By the time COVID-19 was first identified, the virus had firmly established itself in Wuhan. ”

Kristian G. Andersen, director of infectious disease genomics, translational research institute at Scripps Research, told CBS News that “none of (Redfield’s) comments” on the lab theory are “supported by evidence. available ”.

“It is clear that not only was he the most disastrous CDC director in US history where he completely failed in his sworn mission to protect the country, but through his comments he also shows a complete lack of basic evolutionary virology, ”said Andersen.

Andersen was the lead author of a study published in Nature Medicine last year that found the virus to be the product of natural evolution. Additionally, through analysis of publicly available genome sequence data, scientists “found no evidence that the virus was made in a lab or otherwise altered,” according to a press release from Scripps.

“By comparing the genome sequence data available for known strains of coronavirus, we can firmly determine that SARS-CoV-2 arose from natural processes,” Andersen said at the time.

W. Ian Lipkin, co-author of the study with Andersen and director of the Center for Infection and Immunity at Columbia’s Mailman School of Public Health, said that while there is still a lot left, we don’t know about the virus, including exactly how long it has circulated, there is “no evidence” to suggest that it was created in a lab.

“Just because we’ve never seen it before doesn’t mean it was created in a lab,” he said. Lipkin pointed out the ability of the coronavirus to replicate in other animals, such as epidemics in mink, and the emergence of highly transmissible variants in the world – “without any modification of a laboratory” – as proof to the contrary.

“The changes that were exploited by the virus are not what we would have predicted,” he said, adding, “even if we wanted to design such a virus, we wouldn’t have known how to do it. ”

Lipkin called Redfield’s comments “counterproductive,” especially given the increase discrimination and violence against Asian Americans during the pandemic. “We should stop pointing fingers,” he said.

Andersen and his colleagues concluded that the virus most likely originated from one of two scenarios. The first is that “the virus evolved to its current pathogenic state by natural selection in a non-human host and then passed on to humans,” according to the press release. The second is that “a non-pathogenic version of the virus has passed from an animal host to humans and then evolved into its current pathogenic state in the human population”.

“We know that bats carry viruses very similar to SARS-CoV-2, so it’s plausible that it came directly from bats. Like SARS, it’s possible that it came from an intermediate host – which we haven’t identified, ”Andersen explained. “There is absolutely nothing unusual in the fact that we haven’t found such an intermediate host (if there even exists in the first place) and anyone who says otherwise has simply not read the literature.” . ”

Current CDC director Dr Rochelle Walensky told Friday’s briefing that the White House team is “eagerly awaiting” a report from the WHO that “examines the origin of this pandemic and SARS -CoV-2 in humans ”. But China did not come with information that may be essential for a full understanding.

Andersen noted that “we do not know the origins (reservoirs) of most viruses that infect humans, “including other recent viruses like Ebola,” and for those we have some idea of, it can take decades. ”

“We know that the first group of epidemiologically linked cases came from the Huanan market and we know that the virus has been found in environmental samples – including animal cages – in the market,” he said. . “Any ‘lab leak’ theory should account for this scenario – which it simply cannot, without invoking a major conspiracy and covering up by Chinese scientists and authorities.

His scathing conclusion: “Redfield has no idea what he’s talking about – clearly and plainly. This is no surprise given his disastrous tenure as director of the CDC. ”

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