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


Dr. Robert Redfield, former director of the Centers for Disease Control and Prevention, told CNN that he believes the coronavirus originally escaped from a laboratory in Wuhan, China. But a team of experts from World Health Organization, Dr. Anthony Fauci, and several virology experts have said that the evidence to support such a claim simply does not exist.

“I don’t think this happened in any way of a bat to a human. And at that point, the virus reached humans, it became one of the most infectious viruses that we know of in humanity for human-to-human transmission, “Redfield told CNN’s Dr. Sanjay Gupta during a taped interview in January. , which will air in its entirety on Sunday. “Normally, when a pathogen transitions from a zoonot to a human, it takes a while for it to figure out how to become increasingly efficient.

Redfield, a virologist who led the CDC under President Trump, repeatedly emphasized that this is just his opinion, not a proven fact. “Now I can have opinions,” he said. According to Redfield, the extremely rapid transmission of the then-new coronavirus, in his opinion, indicates that it was likely grown in a laboratory for that exact purpose. “Most of us in a lab, when we try to grow a virus, we try to help it grow better, and better, and better, and better, and better, and better so that we can do experiments and find out. The way I put it together. “he said about his theory.

However, Redfield also said he believes the virus started spreading months earlier than previously thought, perhaps as early as September or October 2019, a period of time roughly supported by recent research. That extra time the virus could have spent circulating undetected could help explain how it became “efficient” in transmission, without being “filtered” from a lab.

Dr. Anthony Fauci addressed Redfield’s comments at 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, that would mean it “essentially entered the outside human population already well adapted to humans.”

“However, the alternative explanation that most public health people go through is that this virus was circulating in China, probably Wuhan, for a month or more before they were clinically recognized in late December 2019.” Fauci said.

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

Understanding when the coronavirus first emerged is an important piece of the epidemiological puzzle, which scientists around the world, including a WHO team, I have been working to finalize. A study, recently published in the journal Science, found that “the period between mid-October and mid-November 2019” is “the plausible interval when the first case of SARS-CoV-2 emerged in Hubei province.”

“It is highly 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 before,” the study read. But for weeks or months, its prevalence was low enough to go unnoticed. “By the time COVID-19 was first identified, the virus had become firmly established in Wuhan.”

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

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

Andersen was the lead author of a study published in Nature Medicine last year that found the virus to be a product of natural evolution. Additionally, through analysis of public genome sequence data, the scientists “found no evidence that the virus was manufactured in a laboratory or otherwise designed,” according to a Scripps news release.

“By comparing the genome sequence data available for known coronavirus strains, we can firmly determine that SARS-CoV-2 originated through 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 we don’t know about the virus, including exactly how long it has been circulating , “there is no evidence” to suggest it was created in a laboratory.

“Just because we haven’t seen it before, it 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 buds between minks, and the appearance of highly transmissible variants all over the world – “without any modification from a laboratory” – as proof to the contrary.

“The modifications that have been exploited by the virus are not what we would have predicted,” he said, adding, “even if we wanted to engineer such a virus, we would not have known how to do it.”

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

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

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

Current CDC Director Dr. Rochelle Walensky said at Friday’s briefing that the White House team is “waiting” for a WHO report that “examines the origin of this pandemic and SARS-CoV- 2 in humans. ” But China has not been communicative with information that can be key to a complete understanding.

Andersen noted that “we do not know the origins (reservoirs) of the majority Viruses that infect humans, “including recent ones like Ebola,” and for which we have some idea, may take decades. “

“We know that the first group of epidemiologically linked cases came from the Huanan market and we know that the virus was found in environmental samples, including animal cages, on the market,” he said. “Any ‘lab leak’ theory would have to account for that scenario, which it simply cannot, without invoking a grand conspiracy and cover-up by Chinese scientists and authorities.”

His scathing conclusion: “Redfield has no idea what he’s talking about, plain and simple. Not surprising given his disastrous tenure as director of the CDC.”

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