The US Department of Energy has updated its previously undecided stance on the origin of the pandemic coronavirus, now saying with "low confidence" that it most likely emerged through a laboratory accident, according to a classified intelligence document first reported by The Wall Street Journal on Sunday.
The change reignites a bitter, often partisan, debate over the elusive beginnings of SARS-CoV-2's global devastation, a debate largely fueled by insufficient evidence on both sides.
Still, the Energy Department, which runs national laboratories, is in the minority. Of the eight elements of the intelligence community that have reviewed information on the origin of SARS-CoV-2, only two currently lean toward the so-called "lab leak" hypothesis. The other is the Federal Bureau of Investigation, which concluded with "moderate confidence" in 2021 that the pandemic was ignited by a lab leak, according to the WSJ. It's unclear what evidence that assessment is based upon.
By contrast, four other intelligence agencies and the National Intelligence Council have assessed with "low confidence" that the pandemic was likely sparked by human exposure to infected animals, possibly via animals serving as an intermediate host between a natural reservoir for the virus (such as bats) before leaping to humans.
The two remaining intelligence agencies concluded that there was not sufficient data to coalesce around either the lab leak or spillover transmission hypotheses.
All of the intelligence elements agree that SARS-CoV-2 was not developed as a biological weapon and that China officials did not have foreknowledge of the virus before its emergence in Wuhan at the end of 2019.
Limited data
Many virologists and epidemiologists say a natural spillover transmission appears to be the most likely origin, noting epidemiological and genetic data pointing to this scenario—which has been the case for many other human outbreaks of viruses of animal origin, including those caused by other coronaviruses. In particular, two studies published last summer in the journal Science indicated two viral lineages of SARS-CoV-2 spilled over into humans in two independent events, likely within days to weeks of each other, and most of the earliest cases centered at the Huanan Seafood Wholesale Market in Wuhan, particularly in a section of the market with a concentration of wild animals and virus-positive environmental samples. Collectively, the data and analyses suggest—though can't definitively conclude—that the market contained a so-far unidentified animal or group of animals harboring SARS-CoV-2, which became a prolonged source of infection for marketgoers. And the virus took off from there.
Staunch proponents of the lab leak hypothesis, however, argue that the market was not the origin of the spillover but acted as a setting for superspreader events. They also often point to a 2021 intelligence report suggesting three researchers from China’s Wuhan Institute of Virology got sick with something and sought hospital care in November 2019, as well as ambiguous US State Department cables from 2018 discussing biosafety issues at a Wuhan virology lab.
There remains no confirmed evidence that a SARS-CoV-2 progenitor virus ever existed in the Wuhan Institute of Virology.
“Not a definitive answer”
It's unclear what swayed the Energy Department's stance toward the lab leak hypothesis three years after the pandemic began, as fresh streams of evidence have largely dried up. The WSJ and The New York Times reported that the agency's position was updated due to new intelligence drawn from its network of national labs, some of which are involved with biological research. But officials would not disclose what the intelligence is. A source for CNN noted that the Energy Department's new classified report on the matter was "similar" to information from a House Republican Intelligence Committee report released last year.
National Security Adviser Jake Sullivan declined to confirm or deny the Energy Department's reportedly updated stance on the coronavirus's origins. In a Sunday interview on CNN's State of the Union, Sullivan emphasized the lack of consensus.
“There is a variety of views in the intelligence community,” he said. “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 noted that the Biden administration has pushed to find the truth of the matter.
"But right now, there is not a definitive answer that has emerged from the intelligence community on this question,” he said.