How a single flu shot could protect you for decades

Every year, tens of millions of people in the U. S. get the flu vaccine. That’s because the virus changes year-to-year and protection only lasts around six months. Adolfo Garcia-Sastre https://profiles.icahn.mssm.edu/adolfo-garcia-sastre wants to change that. He’s one scientist working on a universal flu vaccine that could provide decades of protection against all flu illnesses – but only if his team can find the resources that disappeared when U. S. funding dipped. If you liked this episode, listen to our episode on a vaccine trial that could end HIV https://lnk.to/BcnTUp. Interested in more medical innovations? Email us your question at [email protected] mailto:[email protected]. Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave http://plus.npr.org/shortwave. See pcm.adswizz.com https://pcm.adswizz.com for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences. NPR Privacy Policy https://www.npr.org/about-npr/179878450/privacy-policy

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• 0:00Speaker 00

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• 0:16Regina Barber?

  You're listening to Short Wave from NPR. The Centers for Disease Control and Prevention estimates that anywhere from 24,000 to 81,000 people died from the flu during this past flu season. Hundreds of thousands more were hospitalized and millions were infected. And this is a moderate season. In the event of a whole flu pandemic, those numbers could be much higher.

• 0:46Speaker 02

  There is more than 100 potential pandemic flu viruses that could start a pandemic.

• 0:51Regina Barber?

  That's Adolfo Garcia Sastrick, a viral immunologist at the ICANN School of Medicine at Mount Sinai in New York. He's working on a vaccine that could not only protect people from a pandemic flu virus, but all flu viruses. No more annual flu shots. He calls it a universal flu vaccine.

• 1:10Speaker 02

  This shot that we are working on will protect not only against seasonal influenza, not only this year, not only against next year and next year and next year and this year, but also will prevent pandemic influenza from an animal reservoir.

• 1:28Regina Barber?

  A vaccine like this hasn't been possible before because the virus that causes the flu, influenza, mutates every year, evading the previous year's vaccine. But he says-

• 1:40Speaker 02

  The virus cannot change completely. If not, we will not recognize it as influenza.

• 1:46Regina Barber?

  And Adolfo and his team are working on a vaccine that can target all versions of the influenza virus, past, present, and future, if they can find the resources.

• 1:57Regina Barber?

  Today on the show, the science behind a vaccine against all flus and what scientists need to make it a reality. I'm Regina Barber, and you're listening to Short Wave, the science podcast from NPR.

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• 3:39Regina Barber?

  Okay, Adolfo, what about the flu virus impacts why we need a yearly vaccine?

• 3:44Speaker 02

  Yeah, so that's because the virus changes every year. And when we are talking about human influenza, we're talking about three viruses right now.

• 3:54Regina Barber?

  Okay.

• 3:55Speaker 02

  And that's the reason why the vaccine has three components. So there is what they are called the influenza A and influenza B. A comes also in two shapes right now in humans that are called H1 and H3. And H refers to one of the proteins of the virus, the spike of the virus.

• 4:12Regina Barber?

  Okay.

• 4:13Speaker 02

  This is called hemagglutinin. And that's H1 will be hemagglutinin subtype 1. H3 will be hemagglutinin subtype 3. All these three viruses are circulating in people. Some seasons, they are mainly H3s. Some seasons, they are mainly H1s. Some seasons, they are mainly B. But there is always... H1s, H3s and Bs causing infections in humans.

• 4:37Regina Barber?

  Hmm, so flu A which comes into H subtypes and then Bs, okay.

• 4:42Speaker 02

  So we need three components, right? But each one of these viruses change every year. And they do so to avoid pre-existing immunity.

• 4:52Regina Barber?

  Right.

• 4:52Speaker 02

  And the vaccine tries to cover the strains that are circulating. So we make the vaccine for whatever is going to be circulating this year. And the prediction come from the surveillance that has been done for influenza to see what is circulating at any time in the in the year. And sometimes we miss it for at least one of the components. This year, for example, we miss it. For H3s, there was this newest strain that became very quickly, very, very prevalent. And this one was not very well covered by the history component of the vaccine. Still, it provides you some some efficacy, but instead of having perhaps

• 5:35Speaker 02

  an efficacy of 70% prevention from a disease. Then it goes down to 30% because it's mismatched.

• 5:43Regina Barber?

  Right, so all of this refers to current vaccine strategies, like what we do now. That's based on targeting parts of the viruses that change. But what you're working on is targeting regions that stay the same in the influenza virus in order to make this universal flu vaccine. One that we wouldn't need to get every year. Now, historically, there have been barriers to creating this kind of vaccine. What are they?

• 6:06Speaker 02

  So there are there are two types of barriers, the scientific barriers. And the other thing is is more about what type of resources you need to put, which is more of an economical reason than a scientific reason.

• 6:19Regina Barber?

  Yeah.

• 6:20Speaker 02

  The scientific reason is because influenza has conserve areas.

• 6:25Regina Barber?

  The parts of the influenza virus that doesn't change.

• 6:28Speaker 02

  They don't change, yeah, correct. That's what I mean by conserve. But not every conserve area is able to induce an immune response that will be able to protect. So you need to identify these ones that are able to protect. You know, it's like, um, just imagine, you know, that flu is a cow.

• 6:49Regina Barber?

  It's a cow.

• 6:50Speaker 02

  So let's imagine it's a cow.

• 6:52Regina Barber?

  Okay.

• 6:53Speaker 02

  So.

• 6:53Regina Barber?

  Already there.

• 6:55Speaker 02

  So you wanna get protection from a cow, you need to target areas in the cow that will prevent damage to you, right? So perhaps you need to stop or cover the head with foam, let's say that, right? And then the cow cannot do damage.

• 7:11Regina Barber?

  Right.

• 7:11Speaker 02

  Or the feet.

• 7:13Regina Barber?

  Right.

• 7:13Speaker 02

  Then even if they kick you, they cannot do damage. But if you cover the tail, well, the cow cannot give you any damage with the tail.

• 7:22Regina Barber?

  Right.

• 7:23Speaker 02

  So there are some areas in the virus that we call non-protective. So we need to find the protective areas

• 7:32Regina Barber?

  Okay.

• 7:32Speaker 02

  of the virus that are conserved.

• 7:34Regina Barber?

  And protective.

• 7:36Speaker 02

  Yeah.

• 7:36Regina Barber?

  Okay.

• 7:36Speaker 02

  And then we need to induce an immune response against these conserve areas by designing a vaccine that is different from the ones that we have. Because the ones that we have only induce good responses against the variable areas.

• 7:50Regina Barber?

  Variable areas, the parts of the virus that change.

• 7:53Speaker 02

  Yeah, which are very good, but they don't protect you against future strains. They don't protect you against pandemic strains.

• 7:59Regina Barber?

  The science hasn't gotten here yet because we haven't been able to find those regions. Or.

• 8:06Speaker 02

  Well, it took a while.

• 8:06Regina Barber?

  Okay.

• 8:07Speaker 02

  It took a while.

• 8:07Regina Barber?

  Okay.

• 8:08Speaker 02

  Now we have some candidates.

• 8:09Regina Barber?

  Okay, we have candidates and then we have to make a vaccine that will react to these regions that don't change.

• 8:16Speaker 02

  Yeah, correct.

• 8:17Regina Barber?

  Okay, so your lab is working on a universal flu vaccine and you just finished phase one trial. What did phase one tell you?

• 8:24Speaker 02

  So phase one, the main thing that tells you is safety. And the second thing that tells you whether you get. The immune response that you think is good for the vaccine.

• 8:34Regina Barber?

  Yeah, did you?

• 8:35Speaker 02

  Yeah.

• 8:35Regina Barber?

  Wow.

• 8:36Speaker 02

  The phase one, we got induction of antibodies at levels that we think they will be protective. We have not been able to prove that in humans, but we think that the levels that we achieve, they will be protective.

• 8:49Regina Barber?

  So have you started phase two?

• 8:51Speaker 02

  Phase two, we have not started. We are, we have been in phase one.

• 8:56Regina Barber?

  What, what's holding up phase two?

• 8:59Speaker 02

  Uh, money, mainly money.

• 9:00Regina Barber?

  Yeah.

• 9:01Speaker 02

  They are very costly and um, there was a NIH program that was called Civic that was for trying to get improved influenza vaccines. We were part of this program, but this program has been stopped. Uh, and, and right now it's unclear whether it's gonna restart.

• 9:22Regina Barber?

  Was this part of the recent government cuts that happened in the last year?

• 9:27Speaker 02

  Well, it was not really a cut, but there has been also a lot of slowdown

• 9:33Regina Barber?

  Hmm.

• 9:33Speaker 02

  in finances from NIH. So these contracts, they were supposed to at one moment bring clinical trials. But because funding stopped it and there is no call for new proposals yet. And if a call comes, because it takes time to review and then get funded, there's gonna be at least a gap of one year, two years.

• 9:58Regina Barber?

  So what will happen to all your material, all those vaccines in that time?

• 10:02Speaker 02

  The, the problem with the vaccines that we are ready to go is that if they are not going, they need to maintain a stability program and this costs money, money that we don't have.

• 10:16Regina Barber?

  Hmm.

• 10:16Speaker 02

  So we are trying to find partners outside NIH to finance for at least a stability program or if not also for some phase two, phase one clinical trials that we still need to do.

• 10:30Regina Barber?

  How does that feel that you, you know, you could make something that could help so many people, but it get, it gets stopped by money?

• 10:38Speaker 02

  Well, it's frustrating, right? I think the money is there, but, but it's impossible to manage the program on time to be able to renew it again. Because of the amount of changes that have been in NIH. It's also the amount of money that has been put into this program already. You know, it's not trivial. And if we are not able to put this material that we have right now into humans, then it will be lost. And if we want to, in the future, to do it, we need to start again making this material.

• 11:14Regina Barber?

  Are you optimistic that there will be this universal flu vaccine like created in your lifetime?

• 11:20Speaker 02

  In my lifetime, I hope so. But in the next five years, I think it's a big challenge. Because we want to prove not only that it prevents flu the year that we give the vaccine, but also prevents flu the second year, the third year, and the fourth year, right? So just to prove that we have a vaccine that protects for four years requires four years of follow up.

• 11:50Regina Barber?

  So are you optimistic?

• 11:52Speaker 02

  I am. If not, I would not be working on it. But who knows? You know, I'm also trying not to become depressive at the end. This doesn't move forward, right? At least, you know, I really would love if we can prove that this is the way for a flu vaccine. But you know, to me, the discovery process, you know, to me is very exciting also, whether we can translate it into for the good of humanity even better. But just to find new mechanisms is very rewarding for scientists.

• 12:27Regina Barber?

  Adolfo, thank you so much for talking to us today.

• 12:30Speaker 02

  OK, good.

• 12:34Regina Barber?

  If you liked this episode, check out our episode on a vaccine trial that could end HIV. We'll put a link in our show notes. This episode was produced by Burley McCoy, edited by showrunner Rebecca Ramirez, and fact-checked by Tyler Jones. The audio engineer was Maggie Luthar. I'm Regina Barber. Thank you for listening to Short Wave from NPR.

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