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WASHINGTON — The acting director of the National Institutes of Health pushed back on Wednesday against Republicans’ assertions that a lab leak stemming from taxpayer-funded research may have caused the coronavirus pandemic, telling lawmakers that viruses being studied at a laboratory in Wuhan, China, bore no resemblance to the one that set off the worst public health crisis in a century.
Those viruses “bear no relationship to SARS-CoV-2; they are genetically distinct,” the N.I.H. official, Dr. Lawrence A. Tabak, told a House panel, using the formal name for the virus. He added that to suggest otherwise would be akin to “saying that a human is equivalent to a cow.”
