The Washington PostDemocracy Dies in Darkness

Little-known scientific team behind new assessment on covid-19 origins

Small shift in favor of ‘lab leak’ theory was prompted by new data and group of weapons-lab scientists

Updated February 28, 2023 at 4:26 p.m. EST|Published February 27, 2023 at 7:56 p.m. EST
U.S. Ambassador to China Nicholas Burns said Feb. 27 that China needs to be more honest about “what happened three years ago in Wuhan” with covid-19’s origin. (Video: Reuters)
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The theory that covid-19 started with a lab accident in central China received a modest boost in the latest U.S. intelligence assessment after the work of a little-known scientific team that conducts some of the federal government’s most secretive and technically challenging investigations of emerging security threats, current and former U.S. officials said Monday.

An analysis by experts from the U.S. national laboratory complex — including members of a storied team known as Z-Division — prompted the Energy Department to change its view earlier this year about the likely cause of the 2019 coronavirus outbreak, the officials said. Though initially undecided about covid-19’s origins, Energy officials concluded as part of a new government-wide intelligence assessment that a lab accident was most likely the triggering event for the world’s worst pandemic in a century.

But other intelligence agencies involved in the classified update — completed in the past few weeks and kept under wraps — were divided on the question of covid-19’s origins, with most still maintaining that a natural, evolutionary “spillover” from animals was the most likely explanation. Even the Energy Department’s analysis was carefully hedged, as the officials expressed only “low confidence” in their conclusion, according to U.S. officials who spoke on the condition of anonymity to describe a classified report.

The overall view — that there is as yet no definitive conclusion on the virus’s origin — has not changed since the release of an earlier version of the report by the Biden administration in 2021, according to the officials.

“The bottom line remains the same: Basically no one really knows,” one of the officials said.

Still, the news that Energy had shifted its view reignited what was already an intense debate on social media and in Washington, where members of Congress are preparing for hearings — some as early as Tuesday — exploring the circumstances behind the outbreak.

“To prevent the next pandemic, we need to know how this one began,” Rep. Mike Gallagher (R-Wis.), a member of the House Permanent Select Committee on Intelligence, said in response to news of the updated assessment, first reported Sunday by the Wall Street Journal. “The administration must move with a sense of urgency and use every tool at its disposal to ensure that we understand the origins of covid-19.”

U.S. officials confirmed that an updated assessment of covid-19’s origins was completed this year, and said the document was based on fresh data as well as new analysis by experts from eight intelligence agencies and the National Intelligence Council.

But the agencies are united, the official said, in the view that the virus was not developed as a bioweapon.

“‘Lab’ does not equal ‘man-made,’ the official said, noting that lab workers could have collected the virus in nature and stored it at the lab from which it escaped. “Even if it was a leak from a lab," the person added, intelligence analysts "still think it would be a naturally occurring virus.”

Among the nine intelligence entities involved in the assessment, only the FBI had previously concluded, with “moderate” confidence, that covid-19 started with a lab accident. The Energy Department was the only agency that changed its view, while the CIA and one other agency remained undecided, lacking enough compelling evidence to support one conclusion over the other, officials said.

Even at low confidence, however, the Energy Department’s analysis carries weight. For its assessment, the department drew on the expertise of a team assembled from the U.S. national laboratory complex, which employs tens of thousands of scientists representing many technical specialties, from physics and data analysis to genomics and molecular biology.

The labs were established as part of the U.S. nuclear weapons program and operate largely in the classified realm. The department’s cadre of technical experts includes members of the Energy Department’s Z-Division, which since the 1960s has been involved in secretive investigations of nuclear, chemical and biological weapons threats by U.S. adversaries, including China and Russia.

The Energy Department is “a technical organization with tens of thousands of scientists,” said a former energy official. “It’s more than just physics. It’s chemical and biological expertise. And they have a unique opportunity to look at intelligence from the technical aspect.”

Both the Energy Department and the Office of the Director of National Intelligence declined to comment on the revised assessment. It was unclear what, precisely, prompted officials at Energy to see a lab leak as the more probable explanation for how covid-19 began.

Neither of the leading theories — a natural spillover or a lab leak — have been conclusively validated, in part because of China’s refusal to allow independent investigators access to environmental samples and other raw data from the earliest weeks of the outbreak.

Many scientists — and, at least for now, the majority of U.S. intelligence agencies — favor the spillover hypothesis, which holds that the virus jumped from bats to humans, perhaps at a Chinese market, and presumably after passing through a third species that had come to harbor what became known as the SARS-CoV-2 virus. Yet, three years after the outbreak began, the search for the elusive “carrier” species has produced no firm leads. The bats that naturally harbor viruses closely related to SARS-CoV-2 are native to Southeast Asia and southern China, about 1,000 miles from Wuhan, where the first cases of covid-19 were reported.

Likewise, no hard evidence of a lab leak has emerged. Supporters of the leak theory note that the outbreak began in a city that happens to be the world’s leading center for research on coronaviruses. China has had previous lab accidents, including an incident in 2004 in which lab workers were inadvertently exposed to the original SARS virus, and subsequently spread the pathogen outside the lab, resulting in multiple illnesses and at least one death, according to a World Health Organization probe.

China has repeatedly denied that an accident occurred. On Monday, Beijing denounced the new report linking Chinese labs to the pandemic, with Chinese Foreign Ministry spokeswoman Mao Ning demanding that the United States “stop defaming China.”

“Covid tracing is a scientific issue that should not be politicized,” she said.

The Biden administration on Monday emphasized the inconclusive nature of the evidence so far. National Security Council coordinator for strategic communications John Kirby, speaking at a White House briefing, said the new intelligence assessment was part of an ongoing “whole of government” effort to investigate how covid-19 began, although he acknowledged that firm conclusions have remained elusive.

“There is not a consensus right now in the U.S. government about exactly how covid started,” Kirby told reporters. “That work is still ongoing, but the president believes it’s really important that we continue that work and that we find out as best we can how it started so that we can better prevent a future pandemic.”

Director of National Intelligence Avril Haines is scheduled to testify at a Senate worldwide threats hearing next week and probably will be asked to address the matter. The House select subcommittee on the coronavirus pandemic was set to hold a roundtable exploring early covid-19 policy decisions on Tuesday.