"They can't find the bat. The Chinese have been out there looking for the bat and the Chinese would trumpet the bat if they found it because it would take the heat off the Institute of Virology," Swan said recently on ABC.
He was referring to the Wuhan Institute of Virology (WIV), which allegedly received funding from the National Institutes of Health (NIH) to do gain-of-function research. Describing the lab experiments, Swan said: "Two or three years ago they were doing what were called gainer function tests, they were fiddling with the genetic structure of coronavirus to see what would make into a pandemic virus."
Gain-of-function research is a risky area of study that makes viruses even more contagious.
"There's an indication that virologists in the institute got sick in November  with an illness," Swan said. "So there are increasing signs that the institute of virology may well be the source."
The WIV is a biosafety level 4 laboratory, which is the highest level biocontainment certification, but U.S. Embassy officials issued two diplomatic cables warning about inadequate safety at the lab after a visit in 2018. According to the Washington Post, one of the cables warned that the lab's work on bat-based coronaviruses represented the risk of a new SARS-like pandemic.
In May last year, Swan favored the idea that the virus jumped to humans from an animal host in the wild over the lab-leak theory, which he deemed "so unlikely."
"It's on the outer bounds of possibility, but really so unlikely that you could say pretty definitely that it's not the case," he said of the lab-leak theory.
The shift in the narrative may have something to do with the change of administration in the U.S. Critics believe that ABC vigorously rejected the lab-leak theory last year mainly because of the left-leaning media outlet's bias against then-President Donald Trump.
In April last year, Trump said he had a "high degree of confidence" that the coronavirus came from a lab and claimed to have seen evidence to support his certainty.
With President Joe Biden starting to embrace the lab-leak theory, Swan and ABC do as well.
Earlier this week, Biden ordered his intelligence officials to explore it more closely. The shift came after an intelligence report said three staff at the WIV sought hospital treatment for COVID-like symptoms in November 2019.
On Wednesday, May 26, Biden said the intelligence agents were divided on the two possible scenarios: laboratory leak or natural transfer in the wild.
"I have now asked the intelligence community to redouble their efforts to collect and analyze information that could bring us closer to a definitive conclusion, and to report back to me in 90 days," said Biden. "As part of that report, I have asked for areas of further inquiry that may be required, including specific questions for China."
Biden also directed national laboratories to assist with the investigation.
"The United States will also keep working with like-minded partners around the world to press China to participate in a full, transparent, evidence-based international investigation and to provide access to all relevant data and evidence," he said.
But he also said a final answer may never be found given the way that China refused to cooperate in the early days of an outbreak, which has gone on to kill more than 3.5 million people around the world.
Biden's statement marked a sharp turn for an administration that repeatedly expressed skepticism for the lab-leak theory.
During a recent White House briefing, Dr. Anthony Fauci, Biden administration's top infectious diseases expert and director of the National Institute of Allergy and Infectious Diseases (NIAID), said he still thinks the most likely explanation is a natural transfer to humans but that a deeper investigation is needed.
"Because we don't know 100 percent what the origin is, it's imperative that we look and we do an investigation," he said. (Related: Questions over social media censorship of Wuhan lab leak after Fauci admits possibility.)
The World Health Organization (WHO) released a joint report with Chinese scientists in March after a team spent four weeks in Wuhan. But its findings were criticized amid concerns that investigators were delayed and lacked access to original samples.
This week Andy Slavitt, White House coronavirus adviser, said the report had failed to explain how COVID-19 first emerged. "We need to get to the bottom of this and we need a completely transparent process from China," he said.
Swan and ABC are not the only left-leaning journalist and media outlet to have a change of opinion about the lab-leak theory.
On May 1 last year, CNN reported that Trump had "contradicted" the intelligence community by claiming to have seen evidence the virus came from a lab. Four days later, CNN's editor-at-large Chris Cillizza attacked Trump's assertion in his piece titled: "Anthony Fauci just crushed Donald Trump's theory on the origins of the coronavirus."
The Washington Post, New York Times, NPR and Huffington Post were equally dismissive of suggestions that the virus could have come from a laboratory.
On April 30, 2020, the Washington Post published an article headlined "Chinese lab conducted extensive research on deadly bat viruses, but there is no evidence of accidental release;" also on April 30, 2020, the New York Times described the efforts from the Trump administration to get to the bottom of the virus's origins as a political witch hunt; on April 23, 2020, NPR stated: "Virus researchers say there is virtually no chance that the new coronavirus was released as result of a laboratory accident in China or anywhere else;" and on April 7, 2020, the Huffington Post published a story headlined "A Toxic 'Infodemic': The Viral Spread Of COVID-19 Conspiracy Theories."
The narrative started to change in recent months. The left-leaning mainstream media are now publishing stories suggesting the possibility that the virus originated from a Wuhan lab, and interviewing people who believe the lab-leak theory. (Related: Left-wing media conveniently "forgets" they claimed lab origin theory for covid-19 was "debunked.")
Dr. Sanjay Gupta, CNN's chief medical correspondent, spoke on March 26 to Robert Redfield, the former director of the Centers for Disease Control and Protection (CDC). Redfield said that he had concluded the virus escaped from a lab.
On May 24, CNN admitted that there may be more to the Wuhan lab than initially believed. The network published an update: "New information on Wuhan researchers' illness furthers debate on pandemic origins."
On April 30, the Washington Post published an opinion piece urging the World Health Organization (WHO) to carry out an investigation into what happened to determine if the virus did come from a lab.
Earlier this month, two former science reporters of the New York Times – Nicholas Wade and Donald McNeil – both said they now felt it was possible, likely even, that the virus came from a lab.
On May 24, the Huffington Post followed up on the report about the hospitalization of the Wuhan lab workers in 2019. "Wuhan Researchers Were Hospitalized With COVID-19 Symptoms Pre-Pandemic: Reports," its headline said.
NPR shifted its narrative with a March 31 story headlined "Calls For An Open Investigation Into The Possibility COVID-19 Leaked From A Lab."
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