Why the Lab Leak Hypothesis is so Controversial (There’s No Evidence!)

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Alright, I guess I’ve put it off for long enough: let’s talk about the “lab leak” hypothesis — the idea that COVID-19 was either accidentally or deliberately released from a lab studying coronaviruses in Wuhan, China. I’ve only even mentioned this once before, waaaay back in February of 2020, when I said “There is a facility in Wuhan that studies the coronavirus — that name is not new, and is the general term applied to a myriad of diseases including the common cold — but examinations of the virus RNA suggests that the bat coronavirus being studied there shares a common ancestor from about 20 years ago with the one currently causing trouble. So this virus has most likely been out there evolving from host to host for decades. It may have come from a bat, but more likely there’s an intermediary animal that it jumped to, as with MERS, a previous virus that jumped from bat to camel to human, and SARS, which jumped from bat to civet to human.”

And I left it at that, because that’s what researchers knew at the time and most of the people pushing the “lab leak” idea were, well, giant racists who were trying to gin up anti-Chinese sentiment. And what I said was backed up the following month in a paper published in Nature by a coalition of virologists who found that “SARS-CoV-2 is not a laboratory construct or a purposefully manipulated virus.”

But now, a year and a half later, the “hypothesis” is being touted by such papers of record as the Wall Street Journal. So does it have legs? Is it possible that all of these researchers were initially wrong about the origin of SARS-COV-2?

Well of course it’s possible! That’s part of the fun, and frustration, of science as it is being done in real time. We saw the same thing happen with masks, in that at first scientists thought the virus was primarily spread via surfaces, so they didn’t recommend wearing masks. As more data became available, they had a real “oh shit” moment and switched the recommendations. A lot of people think there was some conspiracy to lie to the general public about this to stop them from hoarding N-95s, but a recent FOIA request for Dr. Anthony Fauci’s emails support it, considering that he sent a private email in February of 2020 that cloth masks “are not really effective” at stopping the virus. Later he suggested someone use N-95s. Eventually he found that all masks are at least somewhat effective. The real problem is that the CDC took ages to update their recommendations, literally an entire month after scientists were loudly proclaiming that the data was in, causing the public at large to be suspicious of masks, the CDC, and scientists studying the virus.

So yeah, it’s totally possible that more data can come to light and scientists can change their mind on what is the most likely picture of reality. But is that what’s happening right now with the idea that COVID-19 came out of a lab?

Here’s the short answer: nope! There is currently no evidence that COVID-19 originated in a lab. None. Of course, in the words of someone smart, “Absence of evidence is not evidence of absence.” It’s very difficult to prove a negative, which is why when scientists talk about the origins of this virus, it’s just like when they talk about other things they “know:” we have a lot of evidence that it’s natural in origin and no evidence that it originated in a lab. Because of that, we believe that it’s natural in origin but we do not have evidence that says definitively that it was NOT created in a lab. Therefore, we’d love to see more data to really shore up these observations and come to a more definitive conclusion.

It may surprise you to learn there’s no evidence in favor of a lab leak, because of all the press that it’s gotten. Surely there can’t be all this smoke with no fire, right? It’s mostly conjecture, like “three lab workers had flu-like symptoms before the outbreak (during flu season),” and “there’s a lab right there where the outbreak started (maybe they built it in a place with lots of coronaviruses because they wanted to study coronaviruses, the same way you might set up a whale-watching business where the whales already are. No one thinks boats full of tourists cause whales). But let me talk about the ONE piece of non-conjecture “scientific evidence” people often cite in favor of COVID’s laboratory origins, and which forms the crux of the Wall Street Journal opinion piece.

The WSJ writers (neither virologists — one oncologist and one physicist) write that the key is the “double CGG sequence,” a chunk of the SARS-CoV-2 genome that is rarely found in natural coronaviruses but is often artificially inserted into genomes by scientists looking to “supercharge” a virus. They acknowledge that “Yes, it could have happened randomly, through mutations. But do you believe that?”

But a lot of virologists who study coronaviruses, like Dr. Amy Maxmen and Dr. Vincent Racaniello, do believe that this could happen through random mutations (as that’s how evolution, you know, works). That sequence is rare, but it is in fact found in every coronavirus at varying frequencies. Kristian G. Andersen of Scripps Research Institute pointed out that if the CGG codon had been artificially inserted by scientists trying to supercharge the virus, then as that virus evolves once it’s let loose among the human population we would expect to see it shed that sequence. Instead, researchers have found that the variants have preserved that sequence, offering “*very* strong evidence that SARS-CoV-2 ‘prefers’ CGG in these positions.” Meaning that it’s very likely that this was a natural development.

By the way, you may notice that I had to pull those Kristian Andersen tweets from the Wayback machine. That’s because Andersen recently deleted his Twitter account. Remember those Fauci emails that hit the internet last week? Among them was an email from Andersen himself, in which he warns Fauci on January 31, 2020 that some of SARS-CoV-2’s features “(potentially) look engineered.”

According to Newsweek, “He later added that the “unusual features of the virus” made up a “really small part” of the genome.

Andersen continued: “We have a good team lined up to look very critically at this, so we should know much more by the end of the weekend.”

He added following discussions with his team that they “all find the genome inconsistent with expectations from evolutionary theory. But we have to look at this much more closely and there are still further analyses to be done, so those opinions could still change.””

And guess what happened after that? His team researched the issue and in March they published the paper in Nature that I mentioned at the start of this video, in which they concluded “SARS-CoV-2 is not a laboratory construct or a purposefully manipulated virus.”

He likely deleted his Twitter account because he was being inundated with conspiracy theorists who think all this is proof that he’s being manipulated by China, as opposed to it being the clearest example yet of science working. He started with a hypothesis that this was created in a lab, but the data disproved it. Instead of throwing that pesky data away, he published his results and changed his mind. That’s science. It works.

So if the only real “evidence” is something that was examined by scientist and found lacking more than a year ago, why are respected scientists and people like President Biden asking for more data on the origin of the virus? Because that’s how we stop the next pandemic! Scientists still don’t know what animal, if any, was the intermediary between bats and humans, and how exactly the virus was passed each time. Investigating the origin doesn’t just mean figuring out for sure whether it came from nature or a lab–although it would be extremely helpful to be able to actually completely rule out the lab leak hypothesis so that researchers and the general public can move on.

Sadly, you probably shouldn’t hold your breath on this. Ebola was first identified 44 years ago, and scientists still don’t know its origins. Just as scientists need to be comfortable changing their mind when new data comes in, they also have to be comfortable with the idea that they may never actually find out the “truth” of a situation. And we’d all be better off if non-scientists did the same.

Rebecca Watson

Rebecca is a writer, speaker, YouTube personality, and unrepentant science nerd. In addition to founding and continuing to run Skepchick, she hosts Quiz-o-Tron, a monthly science-themed quiz show and podcast that pits comedians against nerds. There is an asteroid named in her honor. Twitter @rebeccawatson Mastodon Instagram @actuallyrebeccawatson TikTok @actuallyrebeccawatson YouTube @rebeccawatson BlueSky

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  1. Nope; still completely failing to understand why there is controversy over the lab leak hypothesis. There is no evidence for it, and evidence for natural development, so the theory is bunk unless and until new evidence to the contrary comes to light. No controversy there…

  2. My cousin’s boyfriend’s sister worked with someone who heard that the delta variant was launched from a lab in India as a response to the bio attack by China. Prove me wrong.

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