New Swine Flu Concerns Scientists
Speaker 1: 00:00 Our experience with the coronavirus has made us more aware of the threat of viruses. In general, researchers are keeping an especially close eye on new flu viruses that could hit us this fall biologists that use CSD. So they're watching a new swine flu that has emerged in China. The best way to deal with health threats is to understand them so here to help us understand the research and put it in context is [inaudible] Pascal, ganja and evolutionary biologist who specializes in influenza viruses. Thanks for being with us Pascal, Speaker 2: 00:33 Hello there, and a pleasure to be there. Speaker 1: 00:36 So what is it about this new strain of swine flu that's made you and other virus watches around the world? Sort of sit up and take notice. Speaker 2: 00:45 So interestingly, this is a, this is a flu virus and flu viruses have been, uh, quite well known for a long time. And people know that it's worth following what new flu viruses might be around. This one was described in, in pigs and China. Uh, China is home to about half of the world's population, pigs, a half a billion pigs, and the flu viruses can jump from nonhuman animals or birds usually, or pigs to humans. And when they do so they can cause completely novel. And then Speaker 1: 01:18 So, but the issue is, I guess, that the coronavirus is jumping from human to human. That is not the case for this virus yet. Is it? How easy would that be? Speaker 2: 01:27 We don't quite know the answer to this, but there's a couple of findings so that the news is based on a recent, uh, proceedings of the national Academy of science, a paper by a Chinese group. And the disturbing finding is that they find that humans have antibody antibodies against this, this new novel virus that would indicate that at least some humans have being infected by this virus. So that prompted the researchers to ask, well, does this virus suck? Yeah. Is it cause for alarm? And they ran a couple of tests and each one of the tests would actually add a little bit of alarm there's. This virus binds exactly the right molecule on the surfaces of host cells to jump into humans. Uh, it can be tested on, on human airway cells, a cell line or human airways, and it can infect them very well. And to top things off, uh, using the only animal model we have to test transmission. Yeah. Air droplet transmission between animals, the ferret also checked and positive. So the virus seems poised to, um, to, to jump to humans. And so that's the worrying image picture. Speaker 1: 02:37 So is there anything that can be done with newly discovered viruses like this to bring them under control before they sort of start really spreading? And if so, is that happening? Speaker 2: 02:48 So the good news is the influenza researchers, you know, that there all vaccines, we have, we have to make new vaccines every year for influenza because they change is constant. And so year people do surveillance and try to guess which virus will be the next year's major strain. And so the good news is we have effective vaccines against the influence. So unlike the COVID-19 virus much more experienced in producing the virus in, in chicken eggs or animal cells, and then generating vaccines that we have proved do work. Speaker 1: 03:22 Right. Um, there was a strain of, of this virus, the H one N one virus, which we saw in 2009, which did kill about 250,000 people worldwide. But, but then it was brought under control. Why wasn't that virus more deadly? Speaker 2: 03:38 I don't think we have the answer for that. What, what had alarmed, you know, global authorities back in 2009 after the discovery of this virus here in San Diego was that the, the age group really affected by this virus was the most alarming age group. We're talking about 18 to 32 year old people that should have, you know, peak immune, uh, defenses. Okay. And so that hearkens back to the, the 1918 so-called Spanish influenza, which did not start in Spain that killed, you know, between 20 and 40 million people. And that was so terrible because the virus managed to kind of hijacking the immunity of the infected people. So this is an added piece troubling piece of news about this virus based on several prevalence study, meaning studying hundreds of people in China, in households and people working with pigs. You know, many of these people were found to have antibodies against this virus and looking at the age distribution showed that it was the 18 to 32 year olds that had like a third, three time higher rate of being antibody positive. So that would, that would insinuate that this virus knows how to infect people with strong immunity. And that's another very big red flag. Speaker 1: 04:55 Why is it that some people are really not badly affected by flu viruses, some of them not badly affected by the Corona virus even. Speaker 2: 05:04 So they are a little piece of bad news wrapped in glycoproteins and a piece of membrane of the host. They come in and take over. Many of you settled functions so that you cells from then on just make more little viruses, but they require hundreds, if not thousands of parts of your own cells. And these differ between each of us, we are all genetically unique. So each individual is packed with idiosyncrasies of how their cellular machinery might react to a hijacking event by one of these viruses. And so there was a kind of protection in the diversity we have in human populations, meaning that the same virus is very unlikely to be deadly for everyone. Viruses are part of the living world, even though some biologists arguing, given that they have no metabolism are even alive while they replicate and they evolve. And there was a lot of evidence from the study of genomes of the genetic code of living organisms. Speaker 2: 06:06 That viruses are such an integral part of the history of life on this planet that every living animal on this planet. And that is true for plants as well, has a genetic code that is littered with past viruses that have essentially become us. So viruses on, on the one hand, a terrible threat, as we now see with this COVID-19 pandemic and, and, you know, have seen with past influenza, Abe, and dynamics, but they are also constructive agents of evolution. They introduce tidbits of genetic information across species. So viruses are both very bad sometimes and extremely good for introducing novel adaptations into genomes that they in fact, why is it that we're seeing more life threatening viruses spreading recently? I mean, is that true or is it just that we hear about the more, why is this a very good question? You could, you know, there's, there's a couple of possibilities. Speaker 2: 07:07 One could be, we have much more powerful means of detecting viruses, things like polymerase chain reaction, you know, DNA RNA technology that allows you to detect viruses in sewage, for example. But I think there is something else going on. If we, as a species homo sapiens have a disturbed and contacted and penetrated every habitat, you know, including under the deep ice of the ice cores on both poles and in doing so, we come into contact with other organisms or, you know, uh, environments that have not had contact with humans ever. So this notion of us humans as a disturbing force on the ecosystem and, um, by going everywhere and messing everything up, we sample viruses. And some of these are really, really bad news wrapped in an envelope. And so trade is, is an activity that defines humans, right? And, and that opens up think of the pangolin trade, for example, for, for traditional Chinese medicine or the bushmeat trade across Africa, where people eat, consume meat from animals captured in the forest. And so each one of these new contacts is an opportunity for viruses, bacteria, or single cell parasites to infect humans. I'd like to thank you very much for speaking with us. We've been speaking with UCF Petco again, you. Thank you. Thank you so much. Thank you very much, Allison.
