This is circulating today as alleged further evidence of a cover-up, with Fauci dishonestly having reassured the American public that the virus probably jumped from an animal to human while he was quietly whispering to his peers about a possible lab leak.

That’s not what Gottlieb was saying, though, as he clarified later on Twitter.

Former FDA commissioner Scott Gottlieb says he was informed by a senior Trump administration official in spring that Dr. Fauci briefed world health leaders in Europe “that this could have been a potential lab leak…so those discussions were going on.” pic.twitter.com/2OlTg8bMof

— Face The Nation (@FaceTheNation) June 6, 2021

He’s making three points in the clip. First, Fauci took the lab-leak scenario seriously early on, enough so to have discussed it with other scientists. He wasn’t trying to stop his colleagues from considering the possibility. To the contrary.

Second, as the science changed, so did Fauci’s thinking. “Early on we based assessment of risk that SARS-2 leaked from a lab on analysis of its sequence, which initially looked very unusual but on closer exam, less so,” Gottlieb said in a separate tweet. Fauci’s critics have seized on the fact that he was warned via email last February by geneticist Kristian Andersen that the virus’s genome looked unusual, possibly having been engineered by humans. But six weeks later, Andersen had reconsidered and co-authored a study arguing that the genome actually pointed to natural evolution. Andersen has now been hounded off of social media by Fauci critics convinced that he and his study are part of a cover-up and that his initial email to Fauci represents his true view of the virus.

Gottlieb’s telling us that there’s no need for conspiracy theories to explain this. As scientists studied the virus more closely in the first months of the pandemic their thinking about its origins evolved. That’s how science is supposed to work.

Although Andersen’s views appeared to have “evolved” awfully quickly!

“Some of the features (potentially) look engineered,” Andersen wrote in an email to Dr. Anthony Fauci [on January 31, 2020], noting that he and other scientists “all find the genome inconsistent with expectations from evolutionary theory.”…

Just four days later, Andersen gave feedback in advance of a National Academies of Sciences, Engineering, and Medicine letter that was referenced in the prestigious Lancet medical journal to argue against the idea that the virus had been engineered and brand it a conspiracy theory.

In his email, Andersen called the ideas that the virus was engineered “crackpot theories,” writing, “engineering can mean many things and could be done for basic research or nefarious reasons, but the data conclusively show that neither was done.”

How did his position change 180 degrees in the span of four days?

Third, Gottlieb considers the genomic evidence important but not dispositive. A year ago, when all we had to go on was what the virus looked like, the fact that it looked “natural” instead of genetically engineered pointed to an animal origin. A year later, with no animal host found and China resisting attempts to investigate the possibility of a lab leak, the subject has grown more complicated. That said, Gottlieb noted on his Twitter acount this recent piece by virologist Angela Rasmussen and geneticist Stephen Goldstein as another point in favor of the zoonotic origin theory. If you read the splashy WSJ op-ed analysis of the virus’s genome that Ed wrote about this morning, in which two non-virologists argued that SARS-CoV-2 “looks” like it was engineered, be sure to read Rasmussen and Goldstein on why, actually, it “looks” natural. The bottom line for them is that the virus unleashed on the world last year could have been a lot more dangerous than it was — and would/should have been if scientists were tinkering with it in a lab.

The spike didn’t optimally bind to its receptor, ACE-2, and the interaction between the two proteins was unpredictable even using the most advanced computer algorithms. Another key feature often cited as evidence of laboratory origin is the furin cleavage site, where the spike protein is cut in half to “activate” viral material for entry into cells. The viruses most closely related to SARS-CoV-2 don’t have this site, but many others do, including other human coronaviruses. The furin site of SARS-CoV-2 has odd features that no human would design. Its sequence is suboptimal, meaning its cleavage by the enzyme furin is relatively inefficient. Any skilled virologist hoping to give a virus new properties this way would insert a furin site known to be more efficient. The SARS-CoV-2 site has more of the hallmarks of sloppy natural evolution than a human hand. Indeed, a timely analysis last year showed convincingly that it is a product of genetic recombination, a natural feature of coronavirus replication and evolution.

Unfortunately, the pandemic has provided many opportunities to observe SARS-CoV-2 evolution in humans as it unfolds — and confidence in its natural origin has grown over time. The molecular handshake between SARS-CoV-2 and ACE-2, seemingly unique in early 2020, turns out to be found in several related viruses and has since evolved to be a better fit. Its ability to infect human cells also turns out to be unremarkable. A related virus discovered in pangolins infects human cells even more readily than SARS-CoV-2.

Whether you theorize that Chinese scientists were trying to improve SARS-CoV-2 in order to create a bioweapon or trying to improve it via gain-of-function research in order to anticipate how a truly dangerous virus might evolve in nature, the point is that the pathogen that began infecting people in Wuhan in late 2019 was relatively mild — even as lethal as it was. The fact that the coronavirus has already mutated into more efficient strains like the British and Indian variants is further evidence per Rasmussen and Goldstein that the original version of SARS-CoV-2 wouldn’t have been “ready for prime time” if it were genetically engineered.

Although that leads me to wonder if maybe the virus was at some “intermediate” stage of being engineered if/when it leaked from the lab. The way “animal passage” gain-of-function research works, as I understand it, is that scientists take a harmless virus and infect it into an animal, where it will mutate naturally, then harvest that mutated virus and inject it into a second animal, where it’ll mutate again, and so on. I lack the scientific background to answer this question but here it is for those who have that background: Could it be that the virus unleashed on Wuhan was in the process of being engineered via animal passage but escaped from the lab before scientists had managed to perfect it to its most efficient, transmissible form? That is, if the process were expected to involve viral passage through, say, 20 animals, what if there was a lab leak after the tenth pass?

Rasmussen and Goldstein spot another flaw in the lab-leak theory. If SARS-CoV-2 were engineered in the lab, it would have been based on some existing virus. Where is that virus? What alleged building block did the Wuhan scientists use?

The Wuhan institute’s most recent chimeric virus used a very different coronavirus as its genetic backbone. Looking at the body of research produced there, it’s clear that scientists were laser-focused on the bat viruses related to SARS-CoV, which spurred research on coronaviruses worldwide after it emerged in 2003 because of its pandemic potential. There’s just no trace of SARS-CoV-2 in the lab, and if the SARS-CoV-2 progenitor or its building blocks weren’t in the lab before the pandemic, the pandemic could not have started there — even accidentally. This precludes the possibility that SARS-CoV-2 evolved via serial passage in cell culture, or repeated rounds of infection of other cells in a lab, as do other observations about the virus. In standard cell culture, features like the furin cleavage site that are crucial for transmission and disease in humans are rapidly lost as the virus begins adapting to the vervet monkey kidney cells typically used to grow it. For the past 18 months, virologists around the world have been studying SARS-CoV-2 in the laboratory, and they have not seen any evidence that it becomes more dangerous to humans in the lab. The opposite is true: The virus loses features key to transmissibility and virulence, forcing researchers to innovate new culture methods to allow the study of antivirals or vaccines.

Again, I just don’t have the knowledge base to assess that last point. It sounds like Rasmussen and Goldstein are arguing that a virus like SARS-CoV-2 can’t be made more dangerous in a lab, only less dangerous. In which case, what did the virus “start” from?

Here’s where I remind you that Vanity Fair’s blockbuster piece last week claimed that not every virus at the Wuhan Institute of Virology may be known to science. Quote: “Shi’s own comments to a science journal, and grant information available on a Chinese government database, suggest that in the past three years her team has tested two novel but undisclosed bat coronaviruses on humanized mice, to gauge their infectiousness.” Maybe one of those undisclosed viruses was the base for SARS-CoV-2. Or maybe one of them is SARS-CoV-2 and escaped from the lab without scientists there having engineered it, during study. That’s always been a ripe possibility here, it seems to me, although it tends to get lost amid the polarization between the “natural origin” camp and the “lab-leak camp.” It’s possible that the virus did originate naturally in some bat somewhere, was harvested by scientists at the WIV and brought to Wuhan, and then leaked out via contamination in the lab.