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Archived fact-check: Tucker Carlson guest airs debunked conspiracy theory that COVID-19 was created in a lab

Editor’s note, May 17, 2021: When this fact-check was first published in September 2020, PolitiFact’s sources included researchers who asserted the SARS-CoV-2 virus could not have been manipulated. That assertion is now more widely disputed. For that reason, we are removing this fact-check from our database pending a more thorough review. Currently, we consider the claim to be unsupported by evidence and in dispute. The original fact-check in its entirety is preserved below for transparency and archival purposes. Read our May 2021 report for more on the origins of the virus that causes COVID-19.

Li-Meng Yan

stated on September 15, 2020 in an interview on “Tucker Carlson Tonight”:

“This virus, COVID-19 SARS-CoV-2 virus, actually is not from nature. It is a man-made virus created in the lab.”

By Daniel Funke

September 16, 2020


• Scientists say the coronavirus emerged from bats and later jumped to humans.

• The genetic structure of the novel coronavirus rules out laboratory manipulation. Public health authorities have repeatedly said the coronavirus was not derived from a lab.

In a Sept. 15 interview, the most-watched program on cable network television aired a conspiracy theory that has been debunked since the beginning of the coronavirus pandemic.

"Give us, for a non-scientific audience, a summary of why you believe this virus came from a lab in Wuhan," said Fox News host Tucker Carlson during his self-titled primetime show.

Dr. Li-Meng Yan wasted no time.

"I can present solid scientific evidence to our audience that this virus, COVID-19 SARS-CoV-2 virus, actually is not from nature," she said. "It is a man-made virus created in the lab."

Over the next six-and-a-half minutes, Yan, a virologist and former postdoctoral fellow at the University of Hong Kong, explained that the Chinese government created the coronavirus in a Wuhan lab and released it intentionally. The virus’ genome, she said, indicates that it was modified. She accused the Chinese Communist Party of silencing those who claim otherwise.

"It’s hard to be shocked in a moment like this, but you have succeeded in shocking me," Carlson said at the end of the interview. "Unfortunately, this is not the forum for the details of your research; I don’t have the grounding necessary to ask you the right questions."

Scientists do. The consensus of the scientific community and international public health organizations is that the coronavirus emerged from bats and later jumped to humans.

But the doctor’s interview on "Tucker Carlson Tonight" quickly took off, inspiring a rash of social media posts parroting her claims.

"Just now on Tucker Carlson it was revealed that CORONAVIRUS was CREATED in Wuhan Lab and released INTENTIONALLY," says a Sept. 15 Facebook post.

Some of those posts were flagged as part of Facebook’s efforts to combat false news and misinformation on its News Feed. (Read more about our partnership with Facebook.)

After Fox aired its interview with Yan, Facebook labeled the clip — which was posted on the official "Tucker Carlson Tonight" page and shared tens of thousands of times — as false information. It was also flagged on Instagram.

But how do we know Yan’s claims about the coronavirus are wrong — and where do they come from? Let’s review the facts.

Claims run counter to scientific evidence

Scientists worldwide have publicly shared the genetic makeup of the coronavirus thousands of times. If the virus had been altered, there would be evidence in its genome data.

But there isn’t. In March, several microbiology, infectious disease and evolutionary biology experts wrote in Nature — a respected scientific journal — that the genetic makeup of the coronavirus does not indicate it was altered. 

Instead, scientists have two plausible explanations for the origin of the virus: natural selection in an animal host, or natural selection in humans after the virus jumped from animals

"Our analyses clearly show that SARS-CoV-2 is not a laboratory construct or a purposefully manipulated virus," the researchers wrote.

Since that article was published, public health authorities have repeatedly said the coronavirus was not derived from a lab:

  • "All available evidence suggests the virus has an animal origin and is not manipulated or constructed in a lab or somewhere else," said World Health Organization spokeswoman Fadela Chaib at an April press briefing. "It is probable, likely, that the virus is of animal origin."

  • "If you look at the evolution of the virus in bats and what's out there now, (the scientific evidence) is very, very strongly leaning toward this could not have been artificially or deliberately manipulated," Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, told National Geographic in May.

  • "The sequences from U.S. patients are similar to the one that China initially posted, suggesting a likely single, recent emergence of this virus from an animal reservoir," according to the Centers for Disease Control and Prevention.

That doesn’t rule out the possibility that Chinese researchers were studying the virus in a lab when it managed to spread outside the lab, which is something that the U.S. Defense Intelligence Agency has considered. But the agency has also said there is "no credible evidence to indicate SARS-CoV-2 was released intentionally or was created as a biological weapon."

We reached out to Fox News and the email listed on Yan’s paper for comment. The virologist didn’t get back to us. 

Carly Shanahan, vice president of media relations for Fox News, told us that Carlson will address the segment on his Sept. 16 show. 

"Facebook is working hard to make sure you’re unable to see our latest post regarding a coronavirus whistleblower," wrote "Tucker Carlson Tonight" in a related Facebook post. "This is censorship, and we will be addressing it on our show tonight at 8pm ET on Fox News."

Research backed by political operatives

The evidence that Yan cited during her interview with Carlson was backed by nonprofit organizations linked to Steve Bannon and an exiled Chinese billionaire.

Yan has published papers about the transmission of COVID-19 in hamsters and the virus’ shedding patterns in human patients, according to Google Scholar. She has claimed that she was among the first scientists to study the coronavirus outbreak in Wuhan. 

In July interviews with Fox News, Yan accused the Chinese government of knowing about COVID-19 before it publicly acknowledged the virus, and said that her supervisors at the University of Hong Kong ignored some of her research findings. She fled to the United States in April to "deliver the message of the truth of COVID," she said.

But the University of Hong Kong said in a July statement that Yan "never conducted any research on human-to-human transmission of the novel coronavirus at HKU during December 2019 and January 2020."

"We further observe that what she might have emphasised in the reported interview has no scientific basis but resembles hearsay," the university wrote of Yan’s interviews with Fox.

RELATED: What we know about the source of the coronavirus pandemic

More recently, Yan co-published an article that suggests "sophisticated laboratory modification" of the coronavirus. The study was uploaded Sept. 14 to a website called Zenodo, an open-source repository of research — not a peer-reviewed journal. It’s unclear whether the paper received any peer review.

The research is backed by the Rule of Law Society and the Rule of Law Foundation. The sister nonprofit organizations are connected to Steve Bannon, a former chief strategist for the Trump administration, and Guo Wengui, a billionaire and political activist who fled China in 2014 in anticipation of corruption charges from the Communist Party. 

Neither organization has published scientific literature before, according to a Google Scholar search. A website linked to Bannon and Wengui has a history of making inaccurate claims about the coronavirus pandemic.

Our ruling

During an interview on Fox News, Yan said the coronavirus "is a man-made virus created in the lab."

The genetic structure of the novel coronavirus, which has been shared by thousands of scientists worldwide, rules out the possibility that it was manipulated in a lab. Public health authorities have repeatedly said the virus was not created in a lab. Scientists believe the coronavirus originated in bats before jumping to humans. Experts have publicly rebuked Yan’s paper, and it’s unclear whether it was peer reviewed.

The claim is inaccurate and ridiculous. We rate it Pants on Fire!

This fact check is available at IFCN’s 2020 US Elections FactChat #Chatbot on WhatsApp. Click here, for more.


Axios, "Exclusive: Steve Bannon’s $1 million deal linked to a Chinese billionaire," Oct. 29, 2019

Centers for Disease Control and Prevention, About COVID-19, Sept. 1, 2020

The Daily Beast, "Steve Bannon Is Behind Bogus Study That China Created COVID," Sept. 16, 2020

Facebook post, Sept. 15, 2020

Facebook post from "Tucker Carlson Tonight," Sept. 15, 2020

Facebook post from "Tucker Carlson Tonight," Sept. 16, 2020

Fox News, "Chinese virologist: China's government 'intentionally' released COVID-19," Sept. 15, 2020

Fox News, "EXCLUSIVE: Chinese virologist accuses Beijing of coronavirus cover-up, flees Hong Kong: 'I know how they treat whistleblowers,’" July 10, 2020

Fox News, "Hong Kong virologist claiming coronavirus cover-up tells 'Bill Hemmer Reports': 'We don't have much time,’" July 13, 2020

Google Scholar, accessed Sept. 16, 2020

Instagram post from "Tucker Carlson Tonight," Sept. 15, 2020

National Geographic, "Fauci: No scientific evidence the coronavirus was made in a Chinese lab," May 4, 2020

National Library of Medicine, NCBI SARS-CoV-2 Resources, accessed Sept. 16, 2020

The Nation, "Steve Bannon’s Foreign Policy Crusade Against China," Aug. 5, 2019

Nature, "The proximal origin of SARS-CoV-2," March 17, 2020

Newsweek, "The Controversial Experiments and Wuhan Lab Suspected of Starting the Coronavirus Pandemic," April 27, 2020

Newsweek, "Fact-check: Does a New Study Give Evidence that the Coronavirus Was Made In a Lab?" Sept. 15, 2020

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PolitiFact, "Chinese billionaire floats conspiracy about coronavirus victim cremation," Feb. 26, 2020

PolitiFact, "Fact-checking hoaxes and conspiracies about the coronavirus," Jan. 24, 2020

PolitiFact, "No evidence that Chinese officials will say coronavirus was leaked from a lab," Jan. 28, 2020

PolitiFact, "What we know about the source of the coronavirus pandemic," April 17, 2020

Reuters, "Coronavirus very likely of animal origin, no sign of lab manipulation: WHO," April 21, 2020

Science Alert, "Here's How Scientists Know Coronavirus Wasn't Made in a Lab," July 17, 2020

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Tweet from Carl Bergstrom, Sept. 15, 2020 

The University of Hong Kong, "HKU responds to the media concerning a former staff member’s TV interview," July 11, 2020

The Washington Post, "How former Trump adviser Steve Bannon joined forces with a Chinese billionaire who has divided the president’s allies," Sept. 13, 2020

Zenodo, "Unusual Features of the SARS-CoV-2 Genome Suggesting Sophisticated Laboratory Modification Rather Than Natural Evolution and Delineation of Its Probable Synthetic Route,"