The problem for the lab-leak position is that the U.S. has never had access to the Wuhan lab and has thus been unable to reach a definitive answer for more than five years. Now that the CIA has at last come to a conclusion, not all scientists are sold on what it has reported, seeing the results as thinly scientifically sourced.

The CIA says both a natural origin and a lab leak "remain plausible" as potential sources of covid-19, following a review of the pandemic's origins.

The nuanced finding suggests the agency believes the totality of evidence makes a lab origin more likely than a natural origin.