Editor's note: On April 16, news came out that the U.S. government said it was investigating the possibility that the novel coronavirus may have somehow escaped from a lab, though experts still think the possibility that it was engineered is unlikely. This Live Science report explores the origin of SARS-CoV-2.
As the novel coronavirus causing COVID-19 spreads across the globe, with cases surpassing 284,000 worldwide today (March 20), misinformation is spreading almost as fast.
One persistent myth is that this virus, called SARS-CoV-2, was made by scientists and escaped from a lab in Wuhan, China, where the outbreak began.
A new analysis of SARS-CoV-2 may finally put that latter idea to bed. A group of researchers compared the genome of this novel coronavirus with the seven other coronaviruses known to infect humans: SARS, MERS and SARS-CoV-2, which can cause severe disease; along with HKU1, NL63, OC43 and 229E, which typically cause just mild symptoms, the researchers wrote March 17 in the journal Nature Medicine.
"Our analyses clearly show that SARS-CoV-2 is not a laboratory construct or a purposefully manipulated virus," they write in the journal article.
Kristian Andersen, an associate professor of immunology and microbiology at Scripps Research, and his colleagues looked at the genetic template for the spike proteins that protrude from the surface of the virus. The coronavirus uses these spikes to grab the outer walls of its host's cells and then enter those cells. They specifically looked at the gene sequences responsible for two key features of these spike proteins: the grabber, called the receptor-binding domain, that hooks onto host cells; and the so-called cleavage site that allows the virus to open and enter those cells.
That analysis showed that the "hook" part of the spike had evolved to target a receptor on the outside of human cells called ACE2, which is involved in blood pressure regulation. It is so effective at attaching to human cells that the researchers said the spike proteins were the result of natural selection and not genetic engineering.
Here's why: SARS-CoV-2 is very closely related to the virus that causes severe acute respiratory syndrome (SARS), which fanned across the globe nearly 20 years ago. Scientists have studied how SARS-CoV differs from SARS-CoV-2 — with several key letter changes in the genetic code. Yet in computer simulations, the mutations in SARS-CoV-2 don't seem to work very well at helping the virus bind to human cells. If scientists had deliberately engineered this virus, they wouldn't have chosen mutations that computer models suggest won't work. But it turns out, nature is smarter than scientists, and the novel coronavirus found a way to mutate that was better — and completely different— from anything scientists could have created, the study found.
Another nail in the "escaped from evil lab" theory? The overall molecular structure of this virus is distinct from the known coronaviruses and instead most closely resembles viruses found in bats and pangolins that had been little studied and never known to cause humans any harm.
"If someone were seeking to engineer a new coronavirus as a pathogen, they would have constructed it from the backbone of a virus known to cause illness," according to a statement from Scripps.
Where did the virus come from? The research group came up with two possible scenarios for the origin of SARS-CoV-2 in humans. One scenario follows the origin stories for a few other recent coronaviruses that have wreaked havoc in human populations. In that scenario, we contracted the virus directly from an animal — civets in the case of SARS and camels in the case of Middle East respiratory syndrome (MERS). In the case of SARS-CoV-2, the researchers suggest that animal was a bat, which transmitted the virus to another intermediate animal (possibly a pangolin, some scientists have said) that brought the virus to humans.
In that possible scenario, the genetic features that make the new coronavirus so effective at infecting human cells (its pathogenic powers) would have been in place before hopping to humans.
In the other scenario, those pathogenic features would have evolved only after the virus jumped from its animal host to humans. Some coronaviruses that originated in pangolins have a "hook structure" (that receptor binding domain) similar to that of SARS-CoV-2. In that way, a pangolin either directly or indirectly passed its virus onto a human host. Then, once inside a human host, the virus could have evolved to have its other stealth feature — the cleavage site that lets it easily break into human cells. Once it developed that capacity, the researchers said, the coronavirus would be even more capable of spreading between people.
All of this technical detail could help scientists forecast the future of this pandemic. If the virus did enter human cells in a pathogenic form, that raises the probability of future outbreaks. The virus could still be circulating in the animal population and might again jump to humans, ready to cause an outbreak. But the chances of such future outbreaks are lower if the virus must first enter the human population and then evolve the pathogenic properties, the researchers said.
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Originally published on Live Science.
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Jeanna served as editor-in-chief of Live Science. Previously, she was an assistant editor at Scholastic's Science World magazine. Jeanna has an English degree from Salisbury University, a master's degree in biogeochemistry and environmental sciences from the University of Maryland, and a graduate science journalism degree from New York University. She has worked as a biologist in Florida, where she monitored wetlands and did field surveys for endangered species. She also received an ocean sciences journalism fellowship from Woods Hole Oceanographic Institution.
I still will observe and wait for more information. The fact that Wuhan has a level 4 lab in place (known since the 80s) is still troubling imho. Maybe they just had the virus intact as is and were studying it. Seems coincidental to me. But hey you guys are scientists, and you're always right. And propaganda doesn't exist. Stay calm sheep.Reply
Yeah it looks legit and it is good to see. I'm almost ready to take the tinfoil off. 😁 However, is it not possible that it could still be engineered but made not to look engineered?JeetsN123 said:Glad that there's been an article debunking this. It's depressing how many people on the forums think that this virus was manmade.
This article is misleading. Most viruses held in labs are not genetically engineered and originate from natural sources. Just because this virus isn’t genetically modified does not mean the pandemic did not originate from a lab accident. I doubt we’ll ever know the truth, but the fact is, an accidental release from a lab is still plausible especially given the poor laboratory practices in China, notably selling carcasses of lab animals for consumption (!!!).Reply
People simply do not want to believe this is possible, hence articles like this. Not exactly scientifically rigorous.
Sarcasm? I never said I was what you stated. I did know of the lab in the 80s, we monitored it. I merely stated a level-4 facility at the epicenter. I didn't state it was engineered. I stated it seems sketchy as heck scientists are wasting time trying to white knight for China, instead of working on a solution.Open said:Ok Stealth, please share how you choose to live your life. I hope it's more fulfilling than tossing around sarcasm, making yourself seem such the knowledgeable person, and labeling others with a bit of glib. Oh, and do you fancy yourself the 'wolf' in this (and every other propaganda-risk) scenario?
I agree that this virus is/was not "manufactured", but the original report was that it had been isolated from animals, (specifically bats), and was one of several used in experiments on human subjects, and this was the means by which it "escaped". The story is plausible, however I do not necessarily subscribe to it at this time. Given human nature and China's record of secrecy, I doubt that the truth, (if it is even close to this), ever comes out.Reply
The author can't be sure that "The coronavirus did not escape from a lab." What if people got the virus from animal and research on it in lab then by some way it got out?Reply
The only thing we're certain is this virus is not "made in lab".
Stealth said:The fact that Wuhan has a level 4 lab in place (known since the 80s) is still troubling imho.
The only people who could have "known since the 80s" were fortune-tellers and crystal-ball gazers. The Wuhan Institute of Virology's BSL-4 lab opened in 2015.
THis Chinse Virus is either man-made or escaped from the lab or both. So, all of a sudden a virus just manifested itself. Tell that to the dogs and if dogs heard you say that, they probably won't believe it.admin said:A persistent coronavirus myth that this virus, called SARS-CoV-2, was made by scientists and escaped from a lab in Wuhan is completely unfounded. Here's how we know.
The coronavirus did not escape from a lab. Here's how we know. : Read more
See the article at AT: https://www.americanthinker.com/articles/2020/03/the_wuhan_virus_escaped_from_a_chinese_lab.htmlNobody said (except for wild conspiracy theorists) that the virus was made in the lab. However:Reply
1) the lab in Wuhan was working on such viruses,
2) lab workers have been caught previously selling experimental animals in the nearby “wet market” for spare cash, including bats.
3) the Wuhan “wet market” was the epicenter of the disease, as far as we can tell.
There is an alternative concept that I ran into this morning - a PhD who has been studying these viruses for many years has an alternative theory - was sidelined for her research etc... the video has a lot of starter footage but if you go forward you can get to the interview.... (not on Youtube !!!) https://videoplayer.telvue.com/player/0yMvL7SaaePCh8raohYoxsp1MzZ6gHeT/media/546082?autostart=false&showtabssearch=trueReply