A U.S. intelligence report identified three researchers at a Wuhan lab who sought treatment at a hospital after falling ill in November 2019, a source familiar with the matter tells NBC News.
The new details, first reported by the Wall Street Journal, add to the body of circumstantial evidence that supports a hypothesis that the COVID-19 virus may have spread to humans after it escaped from a Chinese research lab in Wuhan. But the evidence is far from conclusive.
A State Department fact sheet put out last year said the U.S. had confirmed "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 common seasonal illnesses."
NBC News reported in February that the U.S. intelligence agencies had not ruled out the possibility of a lab accident, noting that a growing number of scientists are urging an investigation into that possibility.
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