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This episode was filmed on January 19th, 2022.
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For up to date information
on the COVID-19 pandemic,
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check out our playlist linked in the description.
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[♪ INTRO]
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Throughout the COVID-19 pandemic we’ve
seen new variants of concern of SARS-CoV-2,
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the virus that causes COVID-19.
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The World Health Organization gives
names to new versions of the virus
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that it determines might have more of an
impact on people, say by spreading more easily,
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causing more severe disease, or being better
at getting around our body’s defenses.
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The latest variant making headlines is Omicron.
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It was first identified in late November of 2021.
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But as is always the case with this pandemic,
we’re still trying to learn about its effects,
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and what this new variant means for
the overall course of the pandemic.
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Here’s what we know right now.
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Omicron is spreading quickly, and many experts
predict it will overtake the Delta variant
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as the dominant variant of SARS-CoV-2 worldwide.
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You or your loved ones might have already
been affected by it, given its rapid spread.
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Part of the reason for the rapid spread is
that this version of the virus appears to be
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more infectious, meaning more likely to spread
from person to person, than previous ones.
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For example, data from the UK and Denmark
suggest that Omicron is more likely than Delta
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to spread within a household, even in
cases where all members of that household
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had been vaccinated and received booster shots.
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The Danish study is a preprint, meaning
it has not been published or peer reviewed
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but has been uploaded to a pre-publication server.
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There’s no guarantee these preprints are correct,
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as they haven’t been through the
usual process of scientific scrutiny,
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but they are a way to share potentially
important information quickly.
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We’ll be talking about a few
other such studies today.
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With that out of the way, the reason for
the heightened infectiousness might be
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because Omicron is more adept at dodging the
antibody defenses that vaccines give us.
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Take one lab study, published in the journal
Cell, which looked at people who had been fully,
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recently vaccinated with either the
Moderna or Pfizer/BioNTech mRNA vaccines,
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or the Janssen viral vector vaccine.
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Half the people who had been
fully vaccinated, but not boosted,
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couldn’t mount an immune defense against Omicron.
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On top of that, preprint data out of
South Africa suggests previous infection
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with a different variant of the virus also
provides little immunity against Omicron.
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It also showed that people can
become infected more than once.
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However, other preprint data
suggest that the Janssen vaccine
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does provide protection against hospitalization,
so this one might need more time to untangle.
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Why? Well, most of these papers focused on
the neutralizing antibodies our immune system
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produces in response to a vaccine or the virus,
but that’s not all our immune system does.
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So the vaccines may be helping our immune
systems protect us from Omicron in other ways.
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Like the variants that came before
it, Omicron has a number of mutations
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compared to earlier versions, including
many that affect its spike protein.
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These may make it better at both infecting cells,
and avoiding antibodies that target the spike.
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It also seems to affect different parts
of the body compared to previous variants.
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Preprints from Hong Kong and the UK have
found that it’s up to 70 times better
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at replicating in the nose or upper airway than
Delta, which hangs out more in the lungs.
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More virus particles in the nose and throat
could mean it’s easier to sneeze or cough it out
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and help the virus spread.
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Hanging out in the upper airway could also be why
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this variant seems to cause less severe disease.
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This also may be why the reported symptoms
of Omicron are slightly different:
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more runny noses and sore
throats, and more ear aches,
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because everything is congested up here.
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Now, there seem to be fewer hospitalizations
around the world for Omicron than Delta,
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especially for vaccinated individuals.
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And when those hospitalizations do happen,
people tend to stay in the hospital for around
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70% less time regardless of vaccination status,
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according to one preprint
study out of California.
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Plus, a British report from December 2021
found that the risk of being hospitalized
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because of an Omicron infection was
around a third of the risk for Delta.
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This was a pretty small study, though, so take
the numbers with a statistical grain of salt.
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But – and this is a big but – the number of
hospitalizations is going up. And quickly.
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There’s still going to be a subset
of people who become seriously ill,
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even if the variant is milder.
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So if case numbers are high, that still represents
a large overall number of people who will need
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hospital care, and who may develop the group
of long-term symptoms known as long COVID.
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The question on a lot of people’s
minds now is what Omicron means
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for the future of the pandemic.
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One of the big questions is
how the virus will evolve.
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As in, whether we’ll keep seeing not just new
variants, but new variants that are dangerous.
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Researchers have warned that as the virus
continues to spread around the world unchecked,
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that creates opportunities for new mutations
that might turn into a variant of concern.
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So slowing transmission is as
important as it’s ever been.
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Fortunately, we’re not back to square 1.
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We know far more about this
virus than we did in early 2020.
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We know that non-pharmaceutical public
health interventions like social distancing,
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limiting the number of people in enclosed spaces,
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and testing and tracing policies will
continue to play a role in our response.
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Some people have predicted that
COVID-19 will become an endemic disease.
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That is, one where the disease is
always present in the community
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and causing infections on some level.
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However, many other experts point out that that’s
not a good outcome, whether or not it’s likely.
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Seasonal flu is an example of an endemic disease
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that still comes with a
significant death toll every year.
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Endemism is also slightly different from herd
immunity, which you may have heard discussed.
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That’s where most people have immunity
and the disease can only spread
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within particular sub-populations
who aren’t immune.
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And that’s something that experts
were never really banking on,
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despite public figures talking it up.
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Because this virus is just too good at
shifting into new forms for the defenses
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we get from vaccines, or prior
infection, to completely wall it off.
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It’s different from, say, measles,
where vaccination is effective
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at preventing disease in most people.
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But vaccination will still be a valuable tool.
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Expanding vaccination to as many people
as possible worldwide will give the virus
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fewer opportunities to mutate into new
variants, as overall infections decline.
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Plus, some scientists are using data
from all of the known previous variants
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to try to build predictive models
of what might be around the corner.
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A recent study in Science Translational
Medicine looked at what mutations have helped
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a particular virus variant spread in the past.
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The researchers analyzed what features
of that mutation helped it spread,
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and developed a computer model that they used to
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retroactively predict which mutations
have spread up to four months in advance.
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Now they hope to use the model as a starting point
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to help us prepare or screen for new variants.
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So when it comes to Omicron,
we’re not reliving March 2020.
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But there are also still lots of unknowns,
and this is still a dangerous virus.
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So stay safe, everybody.
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And if that’s enough news for you for one day,
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[♪ OUTRO]