The House of Representatives on Friday unanimously voted to declassify information on possible links between the Wuhan Institute of Virology and the Covid-19 pandemic, sending the bill to President Joe Biden.

The Senate also voted unanimously earlier this month to require Director of National Intelligence Avril Haines to declassify such information.

Covid first emerged in Wuhan, China, in 2019, though it’s still unknown how the virus spread to people. Scientists have clashed for years over whether Covid came from an infected animal that transmitted the virus to humans, or whether the pathogen escaped from a lab in Wuhan.

The effort by Congress to declassify intelligence on the origins of Covid comes after the Energy Department concluded with “low confidence” that the virus most likely escaped from a lab in Wuhan as the result of an accident.

The Energy Department is one of 18 agencies that make up the U.S. intelligence community. The department was previously undecided on how the virus emerged.

The Federal Bureau of Investigation has also concluded that the pandemic likely started with a lab incident in Wuhan, the agency’s director, Christopher Wray, told Fox News earlier this month.

“The FBI has for quite some time now assessed that the origins of the pandemic are most likely a potential lab incident in Wuhan,” Wray told Fox News. “Here you are talking about a potential leak from a Chinese government-controlled lab.” 

“I will just make the observation that the Chinese government, it seems to me, has been doing its best to try to thwart and obfuscate the work here, the work that we’re doing, the work that our U.S. government and close foreign partners are doing. And that’s unfortunate for everybody,” Wray said.

Biden ordered the intelligence community in 2021 to provide an updated analysis of how the pandemic emerged. The intelligence agencies were divided on how Covid started spreading among humans, though they said a natural original and a lab leak were both plausible.

Four unnamed agencies in that 2021 report reached low-confidence assessments that an infected animal spread the virus to humans. The intelligence community agreed that Covid was not developed as biological weapon, and most agencies assessed that the virus was not genetically engineered.

The Central Intelligence Agency and another unnamed agency are undecided about whether virus has a natural origin or came from a lab, according to The Wall Street Journal, which first reported the news about the Energy Department’s position.

“Right now, there is not a definitive answer that has emerged from the intelligence community on this question,” White House national security advisor Jake Sullivan told CNN last week. “Some elements of the intelligence community have reached conclusions on one side, some on the other. A number of them have said they just don’t have enough information to be sure.”

Sullivan said that Biden had specifically requested that national labs under the Energy Department participate in the intelligence review of how the pandemic started. He would not confirm or deny reports about the Energy Department’s assessment that a lab leak was more likely.

Dr. Anthony Fauci and Dr. Francis Collins, the former heads of the National Institute for Allergy and Infectious Diseases and the National Institutes of Health, respectively, have maintained that Covid most likely spread from an infected animal to people. Such an animal has not been identified three years after the pandemic began.

House Republicans have called on Fauci, Collins, and other former and current health officials to testify on the origins of the pandemic.

China has denied that the virus escaped from a lab. Foreign Ministry spokesperson Mao Ning pointed to a World Health Organization report published in March 2021 that said a laboratory origin of the pandemic “was considered to be extremely unlikely.”

But the U.S. and 12 other countries sharply criticized the WHO report because the experts who wrote it lacked access to complete, original data and samples.

On the day the report was published, WHO Director-General Tedros Adhanom Ghebreyesus said all hypotheses of the pandemic’s origin are on the table and further studies are needed. Tedros called on Beijing last week to be more transparent.

“WHO continues to call for China to be transparent in sharing data and to conduct the necessary investigations and share the results to that effect — until then, all hypotheses on the origins of the virus remain on the table,” Tedros said a news conference in Geneva.

He also called on the U.S. to share any information it has on the pandemic’s origins.

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