Three researchers at the Wuhan Institute of Virology became sick enough with COVID-like symptoms in November 2019 that they required hospitalization, according to a damning American intelligence report.
The intelligence, which was first reported by the Wall Street Journal on Sunday, adds weight to the Wuhan lab leak theory, which suggests the COVID-19 pandemic originated inside China's only Biosafety level-4 laboratory.
What are the details?
The intelligence is particularly significant because it suggests COVID-19 was spreading in China much earlier than China has admitted. China's communist government traced patient-zero to a man who became sick on Dec. 8. But if researchers at the Wuhan lab were hospitalized one month prior, the virus was likely spreading even earlier than previously believed.
One official familiar with the intelligence described it as "of exquisite quality."
"The information that we had coming from the various sources was of exquisite quality. It was very precise. What it didn't tell you was exactly why they got sick," the official told the Journal.
Another official told the Journal that while the intelligence was potentially significant, it needed further corroboration to be definitive.
The intelligence corroborates a fact sheet released by the State Department in the final days of the Trump administration, which cited classified intelligence and suggested COVID-19 may have escaped from the Wuhan lab via infected researchers.
That report said, "U.S. government has reason to believe that several researchers inside the WIV became sick in autumn 2019, before the first identified case of the outbreak, with symptoms consistent with both Covid-19 and seasonal illnesses."
How did China respond?
China's Foreign Ministry bucked the intelligence, and continued to suggest COVID-19 originated in the United States.
"The U.S. continues to hype the lab leak theory," the foreign ministry told the Journal. "Is it actually concerned about tracing the source or trying to divert attention?"
China's communist government has infamously refused transparency with investigations surrounding the pandemic's origins.
"The Wuhan Institute hasn't shared raw data, safety logs and lab records on its extensive work with coronaviruses in bats, which many consider the most likely source of the virus," the Journal noted.
China has pointed to wet markets in Wuhan as the source of the pandemic.
What did the US government say?
A spokeswoman for the National Security Council reiterated concerns about the pandemic's origins, but declined to comment further.
"We continue to have serious questions about the earliest days of the Covid-19 pandemic, including its origins within the People's Republic of China," the spokeswoman said. "We're not going to make pronouncements that prejudge an ongoing WHO study into the source of SARS-CoV-2. As a matter of policy we never comment on intelligence issues."
The Wuhan lab leak theory has been widely denounced as a conspiracy theory despite a lack of evidence disproving the possibility.
In fact, aside from equally plausible origination theories, only the World Health Organization has said it was "extremely unlikely" COVID-19 came from the laboratory. But their conclusion came after a rushed investigation in which access to critical data was tightly controlled by Chinese authorities.
Indeed, 18 high-profile scientists published a letter this month calling for more investigations into the lab leak theory, saying, "Theories of accidental release from a lab and zoonotic spillover both remain viable."
The group even responded to the WHO's conclusion, which they rebuked because, as they explained, the WHO did not give the Wuhan lab leak theory "balanced consideration," writing, "Only 4 of the 313 pages of the report and its annexes addressed the possibility of a laboratory accident."
Dr. Anthony Fauci, the White House chief medical adviser, also said this month that he is no longer convinced COVID-19 originated naturally.