US intelligence agencies remain divided on COVID-19 origins despite Energy Department's lab leak assessment

In early 2023, the U.S. Department of Energy broke ranks with its own intelligence community by concluding, with what it called "low confidence," that an accidental laboratory leak in China most likely triggered the COVID-19 pandemic. The assessment reignited a question that has consumed scientists, politicians, and public health officials for three years: How did a virus that would kill nearly seven million people first emerge?

The problem is that the American intelligence apparatus cannot agree on an answer. Four other intelligence agencies and the National Intelligence Council lean toward natural transmission—a virus jumping from animals to humans—though also with low confidence. The FBI sides with the Energy Department's lab leak theory, but only with moderate confidence. The CIA, America's premier spy agency, has simply declined to choose, remaining genuinely uncertain. No agency shifted its position after seeing the Energy Department's findings.

Scientists who have studied the coronavirus's genetic structure and its spread patterns tend to favor the natural explanation. They point to the Huanan Seafood Wholesale Market in Wuhan, where the first confirmed COVID cases emerged in late 2019, as the likely spillover point—the moment when a virus circulating in live mammals crossed into human hosts. Researchers examined hospitalization records from before officials began specifically looking for market-linked cases. They mapped the geographic distribution of early infections and found what they describe as evidence of viral spread originating at the market itself. They analyzed samples collected from the market's walls, floors, and surfaces, discovering that positive samples clustered in areas where live animals were sold. Separate genetic analyses of the pandemic's earliest stages suggest, according to some scientists, that the virus infected people connected to the market on two distinct occasions.

But other researchers argue these studies prove far less than their proponents claim. The evidence of two separate market infections could just as easily reflect the virus evolving as it spread person to person, they say. Some scientists have also pointed out that while the Wuhan Institute of Virology has received intense scrutiny, less attention has been paid to another research facility in the city—the Wuhan Center for Disease Control and Prevention—which sits much closer to the seafood market.

The lab leak hypothesis gained political momentum in spring 2020 when former President Donald Trump embraced it, using inflammatory language to blame China for the pandemic. Republican members of the Senate Health Committee published an analysis in October 2022 arguing the pandemic was "probably the result of a research-related incident." That report highlighted what its authors saw as gaps in the natural origins theory and persistent biosafety problems at the Wuhan Institute. It also noted that in 2018, the institute and partners including the EcoHealth Alliance—a research group funded by American taxpayers—had sought Defense Department financing to collect and experiment with coronaviruses engineered to be highly transmissible in humans. The project was rejected for funding. Yet the fact that researchers were actively seeking to create exactly the kind of virus that emerged later struck some scientists as suggestive.

The fundamental obstacle to certainty is China itself. When Chinese researchers arrived at the Huanan market to collect samples, police had already sealed and disinfected the site because people connected to it had fallen ill. Every animal in the market was killed before scientists could test them. Some researchers believe China has provided an incomplete picture of the earliest cases, and they worry that early directives telling hospitals to report illnesses specifically linked to the market may have caused doctors to overlook other cases without such connections, creating a distorted view of how the virus spread.

The National Institutes of Health funded some of the EcoHealth Alliance's work in Wuhan, but NIH officials have repeatedly stated that viruses studied with American taxpayer money bore no genetic resemblance to the virus causing COVID-19. Yet the NIH's acting director acknowledged during a recent congressional hearing that he did not know what other research the Wuhan institute might have been conducting.

President Biden ordered a 90-day intelligence review in 2021, which concluded that both natural origins and lab accident remained plausible. The Energy Department's new assessment, based on classified intelligence unavailable to the public, offers no resolution. What remains clear is that understanding how a pandemic that reshaped the world began matters not only for accountability but for preventing the next one.