Articles, Blog

How Close Are We to a Universal Flu Vaccine?

November 10, 2019


>>Okay, so this is blood from one of our study
subjects, centrifuges, this is kind of PCR row. This is what we call our $100,000 toaster.>>So, do you have any flu virus, here?>>Yeah, and I warned you that
this wouldn’t be very impressive, but that’s a tube, a small tube of influenza.>>We’re here at the Wilson Lab
at the University of Chicago. Researchers here work on influenza. One of the projects they’re working on is
the search for a universal flu vaccine.>>And so, the goal would be to have
a vaccine that you would get one shot and you’d be protected against all
influenza for the rest of your life.>>The search for a universal
flu vaccine is really heating up. What they’re working on here is
one of many projects underway. I wanted to find out how close we are to getting a universal flu
vaccine, and why we really need one. [ Music ]>>Flu is unique. It defies all the paradigms you
have about, for example, measles. You either get infected with measles or you get properly vaccinated
with measles, and you’re done. You’re good to go. You’re not going to get measles, again. Influenza changes. It continually changes.>>These continuous changes are
why seasonal flu vaccines are not as effective as we want them to be. So, is the inherent problem with influenza,
or the inherent challenge with influenza that the virus itself is always changing?>>Yes. But it’s not that simple. We have to redesign the seasonal vaccine every
year, and so there’s an elaborate process by which all the data from the
laboratories around the world is assembled by the World Health Organization, and then
the CDC with the FDA, to look at the viruses out there to say, “Based on what’s out there, what should be the formula
for this year’s vaccine?” But bigger than that is this problem of
the ability of what’s referred to as shift.>>There is so many influenza variants
that are in many different animal species, and the capacity for segment shifts or antigenic
shift to combine the genomes of human influenzas with zoonotic strain influenzas, could make
viruses to which there’s very little immunity.>>And if that virus is created and
that virus has the ability to infect and to be transmissible, that’s the
spark that’s going to trigger a pandemic. It’s that part of it that really scares people.>>About 100 years ago, we had the Spanish flu,
so that was a pandemic that infected a fifth of the world’s population and
killed somewhere between 50 and 100 million people, and that’s just nuts. It’s easy to assume that something like
the Spanish flu couldn’t happen today, because now we have modern medicine, but
actually, the people I spoke with said that we’re more vulnerable now than ever.>>Many more people, much more
density, much more international travel, should a pandemic virus emerge that has that
kind of potential to spread and has that degree of severity, the world would be in trouble.>>When I spoke with Martin Friede at the World
Health Organization, he told me that because of a risk of a pandemic, one of
the greatest benefits of this type of vaccine would be in low-income countries.>>This is Martin.>>According to Dr. Friede, if a pandemic were
to start today, it would take about six months for the first dose of a vaccine to
become available, and about 18 months for a steady supply to be available
in middle- and low-income countries.>>Now, this is where the universal vaccine
has its first and greatest potential impact. Countries that don’t want to use it on a annual
basis because, economically, they don’t see it, they would at least have access to a
vaccine that can be made and stockpiled.>>Everybody I spoke to for this story
talked about the risk of a pandemic, and what they all say is
that it’s not if, it’s when.>>And how do we know there will be a pandemic? You said it’s a matter of time.>>The virus is perpetually mutating. It mutates all the time. The virus grows in birds, it grows in pigs. It grows even in bats and in horses. And there’s more and more of us human beings,
and we’re living in closer and closer proximity to these animals, and this, it’s a numbers game. So, it will happen. [ Music ]>>Researchers around the
world are working together to develop a vaccine that
would prevent a pandemic. One of the approaches is structure-based
design, so let’s take a look at the structure of the influenza virus. It has these proteins on its surface,
and one that’s been interesting for researchers is called hemagglutinin.>>If you picture it metaphorically,
it looks almost like a mushroom or a broccoli with a head and a stalk. The part that’s the head is the one that
induces the dominant immune response. That’s the good news.>>The problem is, the head is also the part
of the virus that tends to change a lot, and so now what researchers are becoming
more interested in is the stalk, or the stem.>>And the stem part of the hemagglutinin
molecule doesn’t change much at all from season to season or from strain to strain.>>The fact that the stem
is conserved is important. If you designed a vaccine that
induced a response against the stem, that vaccine might be effective
against multiple strains of influenza, even when the virus mutated over time. Anthony Fauci’s team is conducting
a phase-one trial of a vaccine candidate that
uses a stem-based approach. In that candidate they’ve put lab-grown
stems on a self-assembling nanoparticle.>>If you look at the hemagglutinin
molecule and you look at the body’s response, the head is much more immunodominant, so if
you wanted to make a response against the stem, but you showed it to the body
associated with the head, the immune system would get distracted a bit
and would make a really good immune response against the head, and maybe a little bit against
the stem, but if you really want to get it against the stem, you remove the distraction
of the head and you put the stem in a way that the immune system sees it very, very
clearly, and when you put it on a nanoparticle, the immune system sees it very, very clearly.>>But that’s only one of the approaches
that’s currently being investigated.>>So, there is actually a lot of space still in
the vaccine and in the influenza vaccine field. So, there is the stalk-based approach,
which is in clinical trials now, has been in two clinical trials, but there
are additional approaches to target things like the receptor-binding domain,
neuraminidase and several other epitopes on the viral hemagglutinin, or
neuraminidase protein that, in combination, would make a multipronged vaccine approach
that we hope could be more effective.>>So, how close are we to a
universal flu vaccine, well, that pie-in-the-sky version,
that perfect version? That’s probably a good ways off. But everybody I spoke to
said that we’ll get there in a stepwise fashion with incremental changes. That incrementally better vaccine
could be just a few years off. There’s so much more to this story
that we couldn’t fit into the video. I hope you check out the article I
wrote about the universal flu vaccine. You can find it on jama.com. [ Music ]

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