How Genetic Infections Made Coronavirus Infectious and Deadly

Robert Bazell, professor of molecular, cellular and Developmental biology at Yale, joins US for coronavirus mutations. Thanks for joining us, Robert, my pleasure. I wanted to talk about coronavirus COVID nineteen and how it's changed. Um, you know, the genetic mutations that have helped turn it into what it is now. Um. You know, there was a time, you know, we think this might have originated in bats and then traveled through

another animal possibly then made its way to humans. There was a time where this might not have necessarily been dangerous to us, but there were mutations that happen over time, and here we are now. So Robert Canny tell us

a little bit about that. Well, it's very common for this process, which is called zoonosis, which means that an animal virus that's harmless in one animal crosses species, it becomes harmful, And of course we care about it that when it happens to human beings, it happens among other species as well. But seventy of emerging infections in the United States and of all infections, are from animals. So is A is a serious source of disease in the

human population and a continuing threat. We were we worried about it a lot in the past. We saw it with stars, which is another coronavirus, the same family as COVID nineteen. But it also happens with influenza, which comes from chickens and pigs and birds and other birds. And we let's do that one again. Influenza is one of the most common ones. But but it circulates constantly through the human population, but it also goes into pigs and chickens and other birds and that causes So that's one

that we're we're very familiar with. There's also a constant fear that avian food, which is another kind of influenza that's in birds will mutate in a way that will become much more harmful the humans. And we've been watching for that for a long time. Is there a particular reason why some of these respiratory diseases like stars and all that in COVID nineteen now, is there a particular reason why they're in bats? Well, a lot of things

are in bats. And the reason that they're in bats is that's make a wonderful home for a lot of creatures because bats are all over the place. If you look at bats in in the rainforest, they are on the top of the trees, they're on the on the floor there, and they're flying all around. So they are

a fantastic vector for all kinds of viruses. And as a result of viruses are very comfortable with them, and from an evolutionary perspective, a lot of times they can move very happily in basses, get around all the time.

I think it's very important, by the way, to point out when we keep talking about bats, and there have been articles about this that people hear about kind of horrible thing where a virus mutates, uh that's harmless to a bat that and becomes a pathogen and human beings that we don't go on some kind of campaign to go out and kill all the bats in the world.

The average bat eats about eight thousand mosquitoes a day, so if you think about what you're losing when you kill a bat, it's pretty significant, and just in terms of the threat the human disease that's caused by the by mosquitoes and other insects and the bats eat for us. In your latest article, you wrote about two critical mutations

that happened with this coronavirus. Can you talk about that. Yeah, these are traced back and then this will take a while to work out, but it's important to understanding that you can't conture you can have more surveillance for this

kind of again into the future. But the best guess is that it was a that virus that was not causing any harm in the bat, that it somehow underwent a mutation either within a bat or within a person or within an intermediate host of some kind of animal that was sold in a food market in China, and it became dangerous to human beings. The specific things that seem to be the most important is that it Uh,

you're excusing. The specific thing that it seems to be most important is that it latches onto a protein called ACE two, a c E T two, which lines the r respiratory system, and that causes to get in destroyer cells and become more dangerous. And there's a second one that involves a protein that's slight is through uh, other proteins that we have on our respiratory system. That makes the binding much more strong and the disease much more infectious.

And the thing we need to be be watching out for is if there would be any further mutations with this coronavirus, with this COVID nineteen, you know, as we race to get vaccines ready and other effective treatments, you know, if it changes mutates in any way, it could possibly change all of that. Yeah, that that's always a concern, and it seldom happens. There have been other viruses that come into the human population, and usually when they do,

they reach a pretty stable state. The evolutionary goal of any creature encoding a virus is to just make more copies of itself. So right now, the COVID nineteen virus is making a lot of copies of itself and it's not under any evolutionary pressure to change, and we've seen that before. I mentioned in the article that j V is which has been around for a long time, probably since the n and it came from is another zoo want to infection. It came from chimpanzees to human beings,

hasn't changed much. Even though there are mutations in the virus, they don't change the biology or it's infectiousness, or it's danger. Robert Bazell, Adjunct Professor of Molecular, Cellular, cellular, and Developmental Biology at the most complicatedly named department in any university. Thank you very much for joining us. Robert, my my pleasures. Thank you all right, Robert Bazell, adjunct Professor of Molecular, Cellular, and Developmental Biology at Yale, Thank you very much for

joining us, My pleasure. I'm Oscar Ramirez and this has been your daily coronavirus update. Don't forget that. For today's big news stories, you can check me out on the Daily Dive podcast every Monday through Friday. So follow us in my heart rate or wherever you get your podcast