JOEL ZINBERG: The Evidence Mounts: A new NIH letter reinforces the lab-leak hypothesis for the origins of Covid-19.

Following laboratory biosafety incidents at government research facilities, the U.S. paused funding on gain-of-function research with influenza and the SARS and MERS coronaviruses in 2014 to determine additional oversight. Researchers conducted the 2017 and 2016 studies discussed in the Senate while this pause was in effect. In 2017, officials lifted the moratorium and replaced it with oversight guidelines for research using potential pandemic pathogens (PPP)—pathogens likely to be highly transmissible, capable of uncontrollable spread, and able to cause significant morbidity or mortality in humans. A PPP resulting from the enhancement of the transmissibility or virulence of a pathogen is called an enhanced PPP (ePPP).

Tabak does not address whether the 2018 WIV experiments he cited in his letter were gain-of-function research. Instead, he maintains that NIH did not consider the WIV experiments so dangerous as to require special review and biosafety measures under the ePPP regulations adopted in 2017 “because these bat coronaviruses had not been shown to infect humans.” But this is an unconvincing technicality.

There are a lot of those.