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0:00
This Week in Virology, the
0:02
podcast about viruses, the kind
0:05
that make you sick. From
0:11
Microbe TV, this is Twiv,
0:13
this Week in Virology, episode
0:15
1109, recorded on April 26,
0:22
2024. I'm Vincent Draconiello, and you're
0:24
listening to the podcast all about
0:27
viruses. Joining me today
0:29
from Fort Lee, New Jersey, Dixon
0:31
de Pomier. Hello, Vincent,
0:33
and everybody else. Looking
0:36
at the window, one would assume
0:38
that since the sun is shining and
0:40
the clouds are all puffy, that it's
0:42
a beautiful day out there, but it's a little
0:44
chilly, and it's a little windy. It's
0:47
not a perfect day, but I think I was told by
0:49
the weather report yesterday that
0:51
Sunday will be spectacular. Here
0:54
in Chelsea, it's 15 degrees
0:57
Celsius and sunny. Also joining us
0:59
from Western Massachusetts, Alan Dove. Good
1:01
to be here, and it's 58
1:04
Fahrenheit, 14 C, and we have
1:07
completely clear skies here. It's beautiful.
1:10
Yep. We're expecting Brienne
1:12
to join us, so she
1:14
will pop in at any moment. She may pop in.
1:17
Vincent, you should have said it says 14 degrees, Chelsea.
1:21
Chelsea. That's very good.
1:23
Sometimes you're funny, Dixon. Inadvertent,
1:26
trust me. Try the veal. I'm here all
1:30
week. If you enjoy these
1:32
programs, these science programs, it's
1:37
WC Fields. We
1:39
would love to have your support, yes,
1:42
because we give you science
1:45
as it is, and not fake
1:47
science. So if you like that,
1:50
go to microbe.tv slash contribute
1:53
so we can reach more and more people.
1:56
A few public servants announcements,
1:59
service announcements. PSA for ASV.
2:03
That's today. If you're interested
2:05
in plant virology, there is
2:07
a special plant virology lunch
2:10
to sign up for at
2:12
registration. If you didn't
2:14
sign up, you can
2:16
change your registration by following the instructions
2:18
from your registration receipt. I
2:21
tried to do that. I couldn't figure it out, but maybe
2:23
you'll have better luck. Will they be
2:25
serving an all meat meal at the plant virology
2:27
lunch? Okay. Right. Well, plants. They
2:30
won't eat plants because they like them, right?
2:32
Right. Right. You
2:34
can also change your registration and consider
2:36
registering for a satellite meeting. If
2:39
you register for anyone, you can go to any of
2:41
the five. These happen the day before. The
2:44
day of the meeting begins in the evening
2:47
with a reception and a keynote and that morning are
2:50
the satellites. So there's an
2:52
invertebrate virology, a veterinary
2:55
virus, a study
2:57
in bats using a one health
2:59
lens virology in a global society
3:01
and navigating virology funding opportunities within
3:04
IHNSF and USD. And
3:07
we have another conference, Pandemic Preparedness Achievements.
3:09
Current challenges and new frontiers. This will
3:11
be 11 to 13 November in Trieste,
3:15
Italy, an overview of
3:17
known and emerging viruses, epidemic risk,
3:20
networking and sharing of information. So
3:23
there's a website that we will put in the
3:25
show notes that you can click on to get
3:27
more information. And here's a
3:29
new conference that I
3:32
recently heard about. And,
3:34
you know, I hear about
3:36
I heard about this at the Ian Lipkin
3:39
Symposium a couple of weeks ago. I sat next to
3:41
the organizer and I said, you know, you ought to
3:43
have a twiv at this
3:46
conference. He said, yeah, that's a good idea.
3:48
Can you advertise it? He said, sure, that's
3:50
a good tradeoff. So this is
3:52
called Molecular Determinants of
3:54
Zoonotic Viruses and Beyond. This
3:57
is going to happen in March of 2025. in
4:01
Freiburg, Germany at
4:04
the university and this
4:07
is Institute of
4:09
Virology there in Freiburg. So
4:12
that's next year and things
4:15
like emerged zoonotic viruses,
4:17
virus-host interactions, molecular-host determinants,
4:19
structural biology and microscopy,
4:21
novel vaccine strategies, therapeutic
4:23
intervention. Let's see
4:25
some conserved speakers. No,
4:29
conserved speakers, right? All right, Brian just
4:31
texted me. She's not coming today. Oh.
4:33
All right, but she was on the schedule. So
4:36
we will just proceed without her.
4:38
We'll just have to gut it out for the three of
4:40
us. John Lavon
4:42
Casanova. See, I had my eye on
4:44
him for a twiv. I
4:47
have Dofogarcia Sastre, Johann
4:51
Nitz, Gustavo Palacios, Tony
4:53
Schaunce, Silke Stertz.
4:55
Now, Silke Stertz figures in one
4:58
of today's paper. Silke
5:00
is in Zurich and I had her
5:02
on a twiv there a couple of
5:04
years ago. She
5:06
discovered the MHC molecule
5:08
as a receptor for bat
5:11
influenza virus, Silke Stertz. Isn't that
5:13
a cool name, Silke? Yes. I
5:16
like different names, not
5:19
Alan and Vincent, you know. Well,
5:21
Dixon is pretty different. Dixon is
5:23
pretty good. That's good, but Silke,
5:25
it's so cool. Name some
5:27
other countries. It can be so cool. I really, really
5:29
like it. So there'll be a link for that in
5:31
the show notes as well. And
5:34
don't forget to buy Dixon's book, The
5:36
New City. You can go to dapalma.com. He
5:38
also has a blog post about it that we
5:40
will link to so you can learn more
5:43
information about it. Thank you,
5:45
Vincent. Now, we
5:48
have some, what
5:51
is it called, in the news, courtesy
5:53
of Amy Rosenfeld, and
5:55
we have an article by, in
5:58
the New York Times. It's an opinion by
6:03
Zainep Tufekki. That looks like a
6:05
Turkish name, doesn't it? Could
6:08
be. It's an opinion columnist,
6:10
actually. And actually, it's talking, she
6:13
talks with Rick Bright. And
6:16
so the problem is the headline, this may be
6:18
your last chance to halt bird flu in humans
6:20
and we are blowing it. This is just, what
6:23
do you call it, Alan? Hyperbole?
6:25
Hyperbole when it, clickbait,
6:27
right? Clickbait, yeah. Come
6:30
on! What
6:33
do you mean halt in humans? It isn't
6:35
doing anything in humans, it's not spreading. Anyways,
6:39
a nice picture of a cow. So
6:42
Rick Bright is an expert on H5N1 and there's a fine
6:47
line between one person and ten. By the time
6:50
we've detected ten, it's probably too late. Okay,
6:53
well you know what Rick? What do you
6:55
want us to do? We have antivirals, we
6:57
have vaccines. Would you like us to call
6:59
all the birds on Earth? Anyway,
7:05
that you should go read it if you can get into
7:07
the times. It's good to
7:11
hear other people's opinions.
7:13
Then we have sequences
7:15
of, I can't
7:19
get to this, here we go,
7:21
USDA publishes sequences of H5N1 on
7:23
a publicly available site, 239 sequences
7:26
from the US
7:28
clade that is currently circulating.
7:32
And what
7:34
I think is interesting is that
7:38
these are still, they don't have any
7:40
human signatures yet. Human
7:43
influenza viruses have certain signatures, which you'll actually hear
7:46
about in one of our papers, and
7:48
these don't have it. It's
7:50
clear that all the cow viruses are from,
7:53
you know, they have a similar origin. Marco
7:56
Warby has said, he
7:59
thinks that the virus may been circulating since late
8:01
2023. And certainly
8:04
this episodic in
8:06
wild animals has been happening since then.
8:08
But the humans, why not? Sure. They're
8:10
cows. Cows. And
8:14
we have a report on measles from
8:16
the CDC. You know, we now have
8:18
128 measles
8:20
cases in 20 jurisdictions.
8:25
So that's the new word for state. Because
8:28
it includes Puerto Rico, right? Right. Because
8:30
it could be Puerto Rico, Guam, Wake,
8:32
etc. Yeah, all those things. Okay. Yeah.
8:34
So they refer to jurisdictions. In this
8:37
case, it's all states. So
8:40
70 of these people have been hospitalized
8:43
so far in this outbreak. So this is
8:45
not trivial. So
8:48
it's increasing. And also
8:51
in England, we have an article from the
8:54
UK. Measles
8:56
is at its highest in
8:59
the UK in
9:01
a decade. Now,
9:04
you may say, why is this? Well, when
9:07
people are reluctant
9:09
to vaccinate, which seems to be a trend
9:11
these days, wouldn't you say
9:13
that? Isn't it a kind of
9:16
trend? Yeah. In certain groups, measles
9:18
virus is one of the first to be
9:20
seen because it's highly contagious. And
9:23
you don't, you know, one person
9:25
can infect many others. It
9:27
spreads in very small droplets
9:29
of respiratory excretions. So this
9:32
is why we're seeing them
9:34
first. But it's, you know, other
9:36
viruses will come back as well.
9:38
You know, according to Paul Offit,
9:40
this is a pushback from the
9:42
mandatory COVID vaccination. Now, parents are
9:44
saying, I don't want my kid vaccinated. So, you
9:47
know, almost every state has a religious
9:50
vaccine exemption that you can choose to
9:52
take. And the parents are saying, no,
9:55
my religion says, I can't take
9:57
a vaccine. And, hmm. You
10:00
know the validity of that is questionable but Paul
10:02
said there's only one religion where it's actually written
10:05
in the Whatever the
10:07
document is for the religion that you can't vaccinate
10:09
yourself. The others is just using it as an
10:11
excuse in my opinion Anyway,
10:13
that's that's bad. You know what measles can
10:15
be bad. So I don't understand
10:18
why you wouldn't immunize your kid What
10:21
do you think measles vaccine is gonna
10:23
do it doesn't cause autism that's been
10:25
shown for decades. Come on folks This
10:27
isn't about facts. Oh, right Vincent
10:33
I want to go back to something you said about the the
10:36
h5n1 in cows the only
10:38
thing that ever if I swear a good Excerpt
10:42
her executive summary of
10:44
that on PBS last night and
10:48
All of the people that were giving
10:50
information were Clear
10:53
to say that all they found
10:55
were sequences. Oh the virus.
10:57
They did not find an entire viral particle. They
11:00
did not Consider it. They tried
11:02
to use milk as an infectious
11:04
agent Two birds and
11:06
it didn't work course and they said this
11:08
these are and then they couldn't
11:10
explain where it came from of course So, you
11:13
know if you look at other in fact, the
11:15
cows are infected Make yeah, but where did the cows
11:17
get it though the chickens? Birds
11:19
the chickens get it birds. Duh. Yeah.
11:22
I mean the chickens we knew it was
11:24
in chickens Yeah, I
11:26
mean more migrating migrating wild boar
11:28
migrating birds who happened past the
11:30
dairy herd so the farms in
11:33
some areas are collection
11:35
areas for migrating birds and
11:37
it's true particularly in Israel
11:40
where you have a lot of farming
11:42
in the surrounding and it's all desert and
11:45
You've got these wild birds coming out of Africa and
11:48
that's I mean, that's where the age of the West
11:50
Nile virus first started I think But
11:54
think of all the food that's available on a
11:56
farm to the animals and
11:59
there are other animals animals out there that want to take advantage
12:01
of that as well so that it's
12:03
very easy to make the association as to where it might
12:05
have come from. Yeah, the milk doesn't
12:08
have infection virus in it. Not at all.
12:10
I'm not worried about the milk. I'm worried about the cows
12:12
infecting people. No, but people might get the wrong idea because
12:15
they don't have the truth. But in Ohio, I was just
12:17
in Ohio and they have a lot of infected
12:20
cows there. And then people are getting
12:22
infected, but they said they're mainly getting
12:24
conjunctivitis. And they're people who work with
12:26
cattle. Yeah, they work with cattle, right. Like,
12:30
you guys work with me and I work with
12:32
you and there are people who work with cows.
12:34
But they don't do it over
12:36
a video conference. Where seldom is
12:38
heard. We can get it. We
12:42
can work with cows here at Microbe TV, but
12:44
we don't have a lot of room. No, we
12:46
could use minicows though. They have little minicows. They
12:48
have minicows, really? They do. They
12:50
do. What do you do with a minicow? Tiny
12:53
little cows. They have minipigs, minicows. Are they pets?
12:56
You get tiny amounts of milk. You
12:58
get half, that's right. You get half points.
13:01
By the way, I wanted to, in the
13:03
CDC page about measles, there's
13:06
a chart on vaccine coverage. So there's a
13:08
map of the US and it colors each
13:10
state according to vaccine coverage.
13:14
And so measles requires 90 to
13:17
95% or more coverage with
13:20
vaccine to prevent outbreaks. And
13:23
so California, Montana,
13:27
Nebraska, Maine, New
13:29
York, a bunch of states around
13:31
here. Massachusetts. Massachusetts, Connecticut, Rhode
13:33
Island, Virginia, West Virginia, Delaware, Maryland,
13:35
Tennessee, and Alabama. Are you guys
13:37
proud that I could name them
13:39
by looking at the shape? That's
13:43
good identification of the jurisdictions. The
13:45
jurisdiction. So they're all 95% plus. But then we have a
13:47
lot of states that are 90 to 94. And
13:52
then we have a good number, 1, 2, 3, 4, 5, 6, 7,
13:54
8, 9, 10 states that are less than recipe
14:00
for measles outbreaks. Come
14:03
on, states like, what
14:06
would that be? Ohio. Ohio
14:08
for sure. Wisconsin, Iowa,
14:11
Minnesota. Yeah,
14:14
Georgia, Oklahoma, Colorado, Arizona,
14:16
Idaho, and Hawaii. And
14:19
Hawaii, oh yeah. So
14:22
if anything, this proves that Alan and I
14:24
can recognize states by their shape. There's
14:27
also, I cheated
14:29
a little bit with Iowa because I knew
14:31
it was one of those rectangular Midwestern states.
14:33
Oh, you hover over it. And I hovered
14:35
over it. I didn't do that. I
14:37
didn't do that. But anyway, check that out. That's
14:39
really good. All right,
14:42
we have a snippet and a paper
14:44
for you today. And the
14:46
snippet is a nature communications paper
14:49
called Positive Selection Underlies
14:52
Repeated Knockout of ORF5
14:54
in SARS-CoV-2
14:56
Evolution. And the authors
14:58
are Wagner, Kistler, Perchetti,
15:00
Baker, Frisby, Torres, Aragona,
15:02
Eun, Figgins, Greninger, Akaks,
15:05
Oltin, Roychoudyri, and Bedford. Trevor Bedford
15:07
is a senior author and we
15:09
had Trevor on to live
15:11
last summer at ASV. That is what I
15:13
think you said ORF5. I think it's ORF8.
15:16
Did I say ORF5? You did. I
15:19
wonder why I would do that. I don't know. Well,
15:22
it's ORF8. It is ORF8. It's ORF8.
15:25
And this and the other paper we'll be talking about
15:27
are both open access. And
15:30
the ORF stands for Open Reading
15:32
Frames. So that's the first thing
15:34
I wanted to mention. This is
15:36
a protein encoded by the genome of
15:38
SARS-CoV-2. And now
15:40
proteins can have cool names like spike
15:43
and nucleocapsid protein because we know what
15:45
they do. But ORF8, we
15:47
didn't know what it did. So we just
15:50
called it an open reading frame. It's an open
15:52
reading frame in the sense that it could be
15:54
translated into a protein. We now know that it
15:56
is. And so we just call the protein. Is
15:58
it start codon? stop code on
16:00
all that stuff. Right. Now, I've
16:03
been interested in ORF8 for a long time
16:06
because I heard a talk by Christian Drosten
16:10
back in 2019 or 2018.
16:12
I don't remember when it was in
16:14
Rotterdam at a virus meeting. Well, he
16:16
talked about the fact that this ORF8,
16:18
early in the SARS epidemic
16:20
in 2002-3, right, was
16:26
lost and all subsequent
16:28
isolates had a deletion.
16:31
And there was some
16:33
suggestion that maybe it
16:37
was less virulent in people also. But,
16:39
you know, it was lost early on
16:42
in the outbreak. SARS-1 didn't go very
16:44
far. It went 8,000 cases. And
16:47
I blogged about that in January of 2020. COVID
16:50
was just getting going. And I remember this
16:52
and I heard that SARS-CoV-2 had an ORF8.
16:55
So I said, you know, it'd be interesting
16:57
to see if this thing
16:59
gets deleted in SARS-CoV-2.
17:03
It's completely different ORF8 than the SARS-1,
17:06
though, I presume. Well, it's
17:08
a similar protein. A similar protein.
17:10
Yes. So this paper is
17:12
all about, it turns out that now I
17:14
think over 90% of SARS-CoV-2 isolates have
17:17
lost ORF8. So
17:21
this is a computational paper which
17:23
tries to understand what is driving
17:25
the loss. Right. So
17:27
they presented at the beginning three
17:29
hypotheses. This could just be that
17:32
ORF8 happened to be deleted
17:35
in the context of some other mutation
17:37
or whatever that was advantageous. And so
17:39
it hitchhiked. It
17:42
could be that it was
17:45
like a neutral change, you
17:47
know. Or
17:50
it could be, yeah,
17:53
so it could be that
17:56
it's linked, hitchhiked basically the
17:59
first two. hypotheses are very
18:01
similar. It's different scenarios where
18:03
it would hitchhike. And the third is
18:05
that deleting ORF8 is actually good for
18:07
viral fitness in humans. Right. Yeah,
18:10
so the deletion would be improving the fitness.
18:12
And so this paper looks at
18:14
that. And if you're wondering, ORF8 protein has
18:16
been studied a lot. And
18:19
it's not just in, this
18:22
deletion is not just in SARS-CoV-2,
18:25
but also in Pangolin, coronaviruses,
18:28
and Mink isolates. So
18:33
it's basically an immune
18:35
evasion protein. It's
18:37
got a lot of functions, like it helps
18:39
down-regulate major histocompatibility Class
18:42
1 molecules from the surface, which
18:44
would be an immune antagonist. And
18:47
it decreases a lot of other immune
18:49
activities. And they
18:51
think it might even contribute to
18:54
cytokine storms by
18:56
activating what we call the IL-7
18:58
pathway. So it's involved in immune
19:01
evasion. Okay, so it's not essential
19:04
for a virus reproduction. You could take it down,
19:06
the virus will still reproduce. Although in a host,
19:08
it may have an altered interaction with the host.
19:10
But given all of its effects
19:12
or apparent effects on immune evasion, it's not
19:14
the kind of gene you would expect to
19:16
go away. Seems like it ought to be
19:19
useful. For sure, an
19:21
immune evasive gene would be
19:23
very useful for a virus. Yeah. But
19:27
unless that usefulness is balanced
19:29
by some negative fitness
19:32
impact or something like that. Right, like
19:34
maybe, yeah, that's useful in, well, what
19:36
they're going to get to later in
19:38
the paper is maybe that's useful within
19:40
the host, but it inhibits your ability
19:42
to spread between hosts, in which case
19:44
there'd be a pressure against it. So
19:48
that's very interesting because T-cell
19:52
escapients of viruses are
19:54
only useful within hosts because
19:56
the way they're
20:00
that works is that you
20:02
involve MHC molecules and that's
20:04
so polymorphic that a CTL
20:06
escape mutant in one person is of no
20:08
use to someone else. So it's only good
20:11
in host. But that's fine because
20:13
those are long-term infections of many years.
20:15
So for D-cell
20:17
reactivity to be lost can
20:20
aid the virus. So that's
20:22
a real-world example of that. So
20:24
what they do here is a
20:26
computational analysis of sequences of
20:29
SARS-CoV-2 from Washington. I
20:32
don't have to say state. It's
20:34
Washington. If it's
20:36
D.C., we say Washington, D.C. If it's
20:38
Washington, it is the state
20:40
known as Washington. Why do people have
20:43
to write Washington state, Alan? Because
20:45
they're from D.C. and they think Washington means
20:47
D.C. And we should point out all of the
20:51
authors are from Washington.
20:53
Full stop. University of Washington, Fred Hutch
20:55
and HHMI. They
20:59
did a lot of sequencing. Remember, they had the first
21:02
U.S. case diagnosed, right? Oh,
21:04
in the Washington Department of Health. They
21:06
did a lot of sequencing.
21:09
So they have great coverage.
21:11
So this paper, they take
21:13
sequences from February 2020 to
21:15
March 2023. And it's emitting
21:17
Omicron because Omicron had its
21:19
own incredibly powerful selection. So
21:22
they look at all the others. So the idea
21:24
here is to understand what is
21:26
driving the loss of ORF8. And so they have great
21:28
sequencing coverage here.
21:35
And so they look through all their samples. They have 14,929 samples
21:37
with a potential knockout
21:40
of ORF8. And there's a lot of
21:43
trickiness about identifying knockouts, which I won't
21:45
go into. But it's
21:47
not so straightforward, as you
21:49
might guess, because there's sequencing errors and so forth.
21:51
And you just don't know. Most
21:54
of the knockouts were found in variants
21:58
descending from alpha. Remember? alpha, the very
22:00
first variant to arise. And those
22:05
variants have most of the loss
22:08
of ORF8. And loss of
22:10
ORF8 occurs by the introduction
22:12
of a stop codon, a
22:14
premature stop codon, right? And
22:17
this is, ORF8 is made from its own
22:19
mRNA, so it doesn't matter if it's downstream.
22:26
It doesn't affect anything downstream. So,
22:28
Vincent, this happened sometime after
22:30
the pandemic, of course. So,
22:33
do they pinpoint exactly when it lost
22:35
the ORF8? Well,
22:39
some lineages
22:41
lost it and some didn't. So,
22:47
it's not universal. There
22:51
are lineages where it lost it and
22:53
lineages where it didn't. And
22:55
what they do subsequently, which I think Vincent was probably
22:57
about to get to, is they
23:00
look at those lineages and how successful they
23:02
were subsequently, right? Yeah,
23:07
I think it was quite early in the pandemic
23:09
when you started to see the loss. I
23:12
don't remember. Let's see if
23:14
this tree does. Yeah, it hasn't been
23:16
fixed in the
23:19
viruses spreading in humans. So,
23:21
what was the figure? 90% of
23:24
circulating SARS-CoV-2 has ORF8
23:26
knocked out, but that means about
23:28
10% doesn't. Some of
23:30
them still retain it, yeah. All
23:33
right, so they
23:36
look at these thousands of samples, and
23:38
I said most of the derivatives of
23:40
alpha have the
23:42
loss, and
23:46
most of these losses are by premature
23:49
stop codons. So, basically,
23:51
and most of
23:53
the stop codons occur very near the end terminus
23:56
of the protein. I
23:58
think about 26 amino acids are left before. this
24:01
stop codon. So there's no big
24:03
piece of protein left that could have some
24:06
function. It's 26 amino acids is not enough
24:08
to do anything. They
24:10
compare the loss of orphae
24:12
to other genes in SARS-CoV-2 and this
24:15
is knocked out way more frequently than
24:17
any other gene. Some other genes are
24:19
lost but this one is way more
24:22
frequent. All right, so
24:26
if a gene loss
24:28
is deleterious to the virus,
24:30
it should be eliminated, right? The loss
24:33
shouldn't occur, it shouldn't perpetuate through
24:35
the virus population. And here as they
24:37
say, they look within the
24:39
host because if the high rate
24:41
of knockout in the sequences they're
24:43
looking at, remember these are consensus sequences from
24:45
people. What
24:48
is also seen in
24:50
host, within host, this
24:52
would argue against deleterious fitness
24:55
associated with the
24:58
knockout. So they look, they
25:00
have some sequences
25:02
from from single hosts where
25:05
they can look at the knockout and
25:07
they find that in fact orphate is
25:09
also lost within host as well
25:12
as without outside of the host. So
25:16
that takes care of
25:18
that hypothesis. The
25:21
other thing they do now for most of
25:23
the rest of the paper is to look
25:25
at positive selection. So
25:27
is the knockout good
25:30
for fitness? So is it
25:32
selected for? And so
25:34
is it good or is it just not bad?
25:37
Yeah, is it good or is it just not bad, right? So
25:40
they use... That's a bromorphic. They
25:43
use the computational
25:46
method which looks at synonymous
25:49
versus non-synonymous changes, right? So
25:51
these are amino acid base
25:53
changes. So a base change
25:55
that doesn't change the amino
25:57
acid is a synonymous change.
26:00
You could think of it as a synonym, right?
26:03
And a non-synonymous change changes
26:05
the amino acid. So
26:07
they look at the ratio of
26:09
non-synonymous to synonymous changes, which you
26:11
can just do by scanning the
26:13
sequences with the computer program.
26:16
And so, for example, if the
26:18
dN over dS is more than
26:21
one, that's indicative of
26:23
positive selection. So that change is
26:25
maintained in all the different isolates
26:28
that you have. If
26:30
it's less than one, it's
26:32
negative selection.
26:36
So it's not good and it's being selected
26:38
about. And one is neutral
26:45
evolution. So if the top and bottom
26:47
are equivalent, it's neutral evolution. So they
26:50
look at ORF8 and
26:52
ask what's going on there. And ORF8
26:54
has a high value,
26:56
greater than one, and
27:01
it's higher than that of any other
27:03
gene, which suggests positive
27:05
selection. And then they
27:07
say, well, there's some caveats here, so
27:09
let's address these caveats. And even after
27:12
addressing the caveats, it still looks like
27:14
the ORF8 deletion is being
27:17
positively selected. So in other
27:19
words, it's of some
27:21
benefit to SARS-CoV-2.
27:24
What that might be, we don't know, but that's
27:27
what the genome is telling us. They
27:29
then quantify that. They
27:31
look at lineages
27:38
of virus that have the ORF8 deletion,
27:42
and they find that these
27:44
are larger than CLAs with
27:48
a synonymous mutation in
27:50
ORF8. So the
27:54
ones with the deletion
27:57
are larger, plus they circulate longer.
28:03
11 and a half days
28:05
for the ORF8 deletion versus
28:08
seven days for synonymous mutation
28:10
in ORF8. So
28:12
we're comparing a deletion versus a synonymous mutation,
28:14
which is a little different, but they said
28:16
we can do this. We
28:18
know what we're doing. Don't try this at
28:20
home, but we know. They have a biostatistics
28:23
license. They're allowed. They
28:26
also look at the rate at
28:28
which these clades with ORF8 deletions grow. In
28:30
other words, you have an
28:32
initial one in an area, and then how fast
28:34
does it propagate? And
28:37
the clusters with nonsense mutations in ORF8,
28:39
that is, that lead to deletions, grow
28:44
6.3 times faster than those with synonymous
28:46
mutations. So the stop codon
28:49
is a non-synonymous mutation, obviously, right?
28:51
Because it changes the amino acid
28:53
to a stop codon. And
28:56
that's why they're treating it as a non-synonymous
28:58
mutation. It's totally fine, yeah. And
29:01
so they say this tells us that
29:03
the knockout is somehow boosting virus fitness.
29:06
Yep. Okay.
29:10
So some function of ORF8
29:13
is not good for fitness. Let's
29:18
see here. They do
29:20
then also discuss the
29:23
possibility, and they can't really sort this out. So
29:29
ORF8 may have
29:32
an advantage within the host and
29:34
a disadvantage spreading between hosts. That's
29:36
the hypothesis, and they present some
29:38
previous work from other groups that
29:40
supports that notion. And
29:44
then the idea is that in a
29:46
chronic infection, which is, we think,
29:48
maybe the source of a lot
29:51
of new variants, you keep ORF8,
29:53
the virus keeps ORF8 because it's
29:55
advantageous in the host and
29:58
in the chronic infectious state. the
30:01
virus is more pressured to
30:03
continue surviving in that host than to
30:05
spread to the next one. And
30:08
that may be the reservoir that prevents the
30:11
orphate deletion from getting fixed
30:13
in the population. So that's
30:17
the source of new orphate coming
30:19
in. They also
30:21
note that so
30:25
many, many changes in spike are positively
30:27
selected for and they're associated with fitness
30:29
gains. In fact, the rate of growth
30:31
of those compared to orphate are similar.
30:34
So they say this is more evidence
30:36
that maybe the orphate is positively selected.
30:40
And also look at whether it's
30:44
found in one clade versus another, one variant
30:46
or one clade versus another. And there's
30:48
some clades that mostly have it, but it's
30:51
also found in others as well. So
30:53
there's no clade-specific association of that. And
30:56
the deletion may decrease pathogenesis.
30:58
That's, again, they
31:01
cite some various evidence on that. Yeah.
31:03
So people have suggested that it reduces clinical
31:05
severity. So then they say, all right, let's
31:08
take our genome sequences and link them with
31:10
outcomes in the disease reporting system.
31:14
And they do this again with
31:16
pre-Omicron because the Omicron itself was
31:18
thought to be... Different story. ...different
31:20
story. So 8% of individuals infected
31:22
with intact orphate were hospitalized. 6.7%
31:26
with orphate knocked out were hospitalized.
31:29
1.8% of individuals infected by intact orphate
31:34
containing virus died compared
31:36
to 1.3%. These are very small differences. But
31:40
I want to remind people, they do
31:42
not take into account population
31:45
immunity, age, comorbidities,
31:47
which could all influence
31:50
this. So I don't... I
31:53
think this needs more study, frankly. It
31:57
may be too late to study that. It may be too late.
32:00
fact, yes. It was... I
32:02
gather that no geographic
32:04
distributions were noted
32:07
or age- Well, this is all a
32:09
study from Washington, right? Well, no, they
32:11
did look at international samples and I
32:14
don't think they found that
32:16
there was any striking, like
32:19
if you're in a particular
32:21
place, you don't get ORF8 deleted.
32:23
It just seems to be consistent.
32:26
Yeah, but
32:28
most of their data is from
32:30
Washington State. I think that's correct
32:32
that it's found elsewhere. I had
32:34
the unfortunate event
32:39
happen to me at the ASTM and
32:41
H meeting in Seattle. Yes. I
32:43
caught and so did you, Vincent. You
32:45
did. Acquired. I
32:48
wondered if we had an ORF8 deletion or not.
32:50
Good question. Maybe.
32:54
Was that December 2022? As
32:57
we know exactly when it was because the
32:59
woman in charge of the exhibits came around
33:01
and shook everybody's hand the morning of the
33:03
opening events. The next day she phoned up
33:05
and said, oh, by the way, I just
33:08
tested positive for Scoville Have
33:11
a nice day. All
33:15
of this, Dixon, have you followed this so
33:17
far? You're kind of the late person here.
33:20
You got it?
33:22
I got whatever there is to get. I mean, I
33:25
don't understand why the deletion occurred. I don't
33:27
understand why the deletion is still there. And
33:30
I don't understand why in the same populations
33:32
there is no deletion. Well, first of all,
33:34
it's not a deletion of the gene. It's
33:37
an introduction of a stop code on. So the protein
33:40
is gone. Oh, that's
33:42
what I meant. It's not really a deletion
33:44
in the genome, right? It's a knockout. That's
33:46
fine. That's fine. So it's best
33:48
to say ORF8 null virus. The
33:50
rows just because random changes happen all the
33:52
time. Why doesn't that happen to the whole
33:55
damn virus and just get rid of it
33:57
then? Well, that's not going to be positive.
34:00
Selective pressure is what that is. No, no,
34:02
I understand. You're trying to find an argument
34:04
why this happened. Right.
34:06
That is something that remains
34:08
a little up in the air. So
34:10
all this paper shows, which is important,
34:13
is that there seems to be a
34:15
positive selection to eliminate
34:18
the orphate protein in human
34:20
infections for SARS-CoV-2.
34:22
And so there's
34:25
some selective pressure that's causing
34:28
the virus to lose this
34:30
protein repeatedly. And
34:34
that's worth investigating further. Yep.
34:37
Oh, yeah. No, no, not part of your... Now,
34:39
they do speculate a little about what the mechanism
34:41
might be. Right. And I
34:43
think this is interesting. So they say that
34:46
an orphate
34:48
protein interacts with spike in
34:51
the endoplasmic reticulum. Okay?
34:54
And it reduces the
34:57
display of spike on the virus
34:59
particle's surface. And
35:02
they've shown that in experiments that it
35:04
leads to less spike on the surface
35:06
of the particle. And what they say,
35:10
that could give you better fitness by
35:12
avoiding the host immune response. Because if
35:14
you have fewer spikes on the particle,
35:16
you're going to be less able to
35:18
be neutralized by antibodies. Right. But
35:20
you may be less able to transmit to the next host. Right.
35:24
Because you have less spike on the viral particle. And
35:27
when you go through a bottleneck of transmitting from
35:29
host to host, that may affect the ability to
35:32
establish new infection. Right. Now,
35:34
they did find an elevated within-host rate
35:36
loss of orphate
35:38
compared to outside of the host.
35:41
Right. So
35:43
these are all acute infections. And we may
35:45
not be seeing the effect of loss there.
35:49
Then they say, you
35:51
know, these not going to have not
35:53
been fixed. First of all, they've not been fixed, only 90%.
35:56
And they've only spread in alpha and
35:59
XBB subclays. and they don't
36:01
know why that is. But one thing they
36:03
do say is very interesting. They
36:07
say this could knock out the loss of, and I
36:09
don't think we should say knockout because it implies that
36:11
I guess it's a knockout. This protein
36:13
loss is an example
36:15
of, maybe an example of what they call
36:17
clonal interference. Okay, so an
36:21
example of that would be that, so
36:24
here's how it would work. XBB
36:27
descendants have ORF8
36:29
knocked out, then suddenly
36:32
BA286 outcompetes
36:35
XBB, and ORF8
36:39
doesn't matter. It's not going to help as much
36:41
because BA2.86 is
36:44
so much more fit than XBB that
36:46
having ORF8 knocked out doesn't matter. And
36:48
so they say that could be
36:50
why ORF8 is not present in
36:53
all lineages. And
36:56
they also say, I think Alan you mentioned this,
36:59
these ORF8 chains are not present
37:01
in chronic infection associated infections, right?
37:05
And they say maybe because
37:09
having intact aid allows persistence and
37:11
evasion of the immune response because
37:13
you have a long-term infection where
37:15
immunity is going to make... Different
37:17
pressures. Different pressures, yeah. So
37:20
they say they hypothesize disproportionate
37:22
contribution of chronic infections to
37:25
global evolution could prevent ORF8
37:27
knockout fixation. So there's a
37:29
good fraction of infections that are
37:31
in, that are chronic and immunosuppressed people. And
37:33
so that could be
37:35
the reason. But you know, these are immunosuppressed
37:38
people, so I'm not sure how
37:40
much of an immune response you need to evade,
37:42
right? There's
37:44
probably some, and it depends on the patient,
37:46
and yeah. Yeah, they're all different. That's true.
37:50
You just have to be careful when you speak in
37:52
these global terms that you are... Really,
37:55
yeah. There's not a
37:57
complete absence of an immune response in every immuno...
38:00
compromised patients. It's different kinds and
38:02
so that may be where Orphate
38:04
is doing it. So I think
38:06
this is interesting and tells
38:09
you that there's probably positive selection
38:11
for Orphate loss and
38:15
now what do we do? Well there's not
38:17
much we can do. This is an interesting
38:19
problem and it's a virological problem
38:21
in my point, my view. I don't think
38:23
it helps
38:25
in any way of surveillance and
38:28
epidemiology. You just get vaccinated and
38:30
you'll be protected, right? Yeah, the
38:33
longer term way I see this helping, I mean of
38:35
course it's always best to know
38:38
more about a serious disease causing virus,
38:41
but I might imagine if we find
38:43
out that Orphate is involved in the
38:46
cytokine storm, we already know that that
38:48
is one of the deadliest parts of
38:50
this and many other viral infections and
38:52
maybe we could target that and
38:56
develop something that's going to
38:58
stop that aspect of it.
39:00
Yeah, yeah. Dixon, you have
39:03
any other questions? No,
39:05
and I don't have any answers either. I
39:08
think the best thing to say at this point is stay
39:10
tuned. Dixon, what's the
39:12
most successful parasite of
39:15
humans? Um,
39:17
toxoplasma. I
39:20
thought so. Yeah, in
39:23
fact it's the most successful parasite period. It
39:26
infects all mammals. Someone had another answer
39:29
and I said no, I think Dixon
39:31
would say toxo. I would definitely say
39:33
toxo. Okay, I
39:36
forgot which one they said but... 10-1 maybe.
39:39
No, it was not a parasite. I forgot
39:42
what it was. All right, so I
39:44
learned that from you anyway. That toxo
39:46
is very successful. Well, I can contribute.
39:48
Among other things. Our
39:50
next paper is also in nature
39:52
communications. How about that? How about
39:54
that? Now, since we've been talking
39:56
about influenza H5N1 viruses, I
39:59
thought we would talk about some
40:01
other influenza virus. And
40:03
this is cross-species spillover potential
40:06
of the H9N2 bat influenza
40:08
A virus. Very cool, H9N2.
40:13
And bat influenza virus. Bat
40:16
influenza, did you know that bats
40:18
could have influenza viruses?
40:20
Well, now you're gonna learn. The
40:22
first author is Rabbe
40:24
El-Shazni. I don't know how many
40:27
co-first there are. There's only one first
40:29
author and only one senior author, Richard
40:31
Webby. Richard Webby.
40:33
I do wanna call out the third from
40:35
last author, Muhammad Ali. Mm. I'm
40:39
sure it's not the same for you.
40:41
I think Muhammad is spelled differently, but. Yes,
40:43
it is. And this
40:46
group is from a whole bunch of
40:48
different places all over the
40:50
world. National Research Center in Giza, Egypt.
40:54
So there's someone from Giza and someone
40:56
from Memphis, but that's the Giza in
40:58
Egypt and someone from Memphis in Tennessee,
41:00
St. Jude Children's Research Hospital. Some
41:03
place called Human Link in Dubai, and I don't know
41:05
if that's a company or a research center. High
41:09
Point University in High Point, North Carolina,
41:11
University of Hong Kong, and
41:14
Scripps in La Jolla. So
41:16
really very global. Have you been to
41:19
Dubai? Yes. Well,
41:23
I wish I had been there during the flood.
41:26
I mean, that would have been an interesting
41:28
time to experience an old
41:30
desert phenomenon that
41:33
has never happened before. But
41:35
yeah, I was there when the Burj
41:38
Khalifa building became
41:40
the tallest building. I was there for the tall
41:42
building council meeting, and it
41:45
was quite an amazing building to look at. It looked like
41:49
from a distance, it didn't look like a building. It almost
41:51
looked like a fountain pen. It
41:53
was so skinny, and so, they
41:55
must have done, or was
41:58
it a wind tunnel work? just
42:00
to make sure that the damn thing wouldn't fall over.
42:03
And I
42:05
was impressed with that, and I was also impressed
42:07
with the fact that there were a lot of
42:09
buildings in Dubai that had their family names on
42:12
them, and the buildings did absolutely
42:14
nothing but just show off the fact that they had
42:16
a lot of money. That's all. So,
42:19
unfortunately, that's still the case.
42:22
So, the senior author, Richard Webby, will be on
42:25
Twivs at some point. I think we're finding a
42:27
date for him to talk about H5N1. So
42:30
that'll be fun. All right. So, most
42:33
influenza viruses, you know, they're in people,
42:35
and the reservoir is waterfowl,
42:38
right? The major reservoir are waterfowl. Many
42:41
mammalian hosts are infected besides
42:43
humans, dogs, horses,
42:45
cows, pigs, et cetera, cats.
42:49
But they've
42:51
been recently found in bats, and we
42:55
covered this first
42:57
paper, Twiv a long time ago, 2009-10. The
43:01
first influenza virus of bats was found in
43:04
a little yellow-shouldered bat in Guatemala.
43:06
I just love the name, little
43:08
yellow-shouldered. Bats, many bats have really
43:11
charming names. Totally
43:14
different from all other known
43:16
influenza viruses. The
43:18
HA and the NA were very different. And
43:21
then another one was found. So that one
43:23
was called H17N10. And
43:28
in 2010, another one was found in Peru in
43:31
New World flat-faced fruit
43:34
bats. And
43:37
this was called A18N11. And
43:41
both of these bats were asymptomatic. They
43:43
weren't sick, and they got
43:45
these influenza viruses from them.
43:48
Now, the cool thing about the
43:50
hemagglutinin of- Yeah, and the H18N11 is also not
43:52
related to any other. Any
43:55
other, right. These are like totally
43:58
bizarre, came from Mars. flu
44:00
viruses. And that paper
44:02
we did on Twift. Now as I
44:05
mentioned earlier, the receptor for the hemagglutinin
44:07
of these viruses is not sialic acid
44:09
as it is for most other
44:12
influenza virus that we know of, but
44:14
it is major is
44:16
to compatibility molecule.
44:20
Class II, and
44:22
that was discovered by a group including
44:24
Silke Schurk. As I told you a
44:27
while ago, she was going to factor in and she's going to
44:29
be at one of those meetings. So
44:33
they use a proteanaceous receptor rather than a
44:35
sugar to enter cells. And
44:38
these viruses in the bats were
44:40
detected in rectal swabs. So
44:44
maybe a fecal oral transmission
44:46
rather than respiratory. Got
44:49
that Dixon? Yeah,
44:52
so up to that point, it
44:54
was pretty much bat influenza viruses
45:00
are off in their own department. They
45:02
use a different receptor. They've got these
45:04
distant relation HNN. And
45:11
then 2017, the virus in this paper
45:14
showed up. Now this virus is H17 and
45:16
H18N11. Bats
45:23
are highly cerebropevolent in Central and South
45:25
America, but not in Europe. So this
45:27
virus could be restricted. Now
45:29
the virus of this paper was
45:31
discovered in 2017 in Egypt from Egyptian fruit
45:34
bats. And
45:37
it's different from H17N10 and H18N11, but
45:39
it is within the H9N2 subtype, which is known
45:49
to be avian influenza
45:51
viruses. So the HA
45:54
and the NA are distinct,
45:58
but the HA is not. in the NA
46:00
or H9N2, right, that's what you get
46:02
that from. And the remaining genes come
46:04
also from avian influenza viruses,
46:06
it looks like. It was first
46:09
found in oral swabs of the bats that
46:12
could be grown in chicken eggs, unlike those
46:14
bat viruses. And inoculating
46:17
fruit bats with the virus in the lab
46:19
gives you an infection. So,
46:23
and also some bat-to-bat
46:26
transmission seem to have occurred in that. So,
46:28
you got now bats have two
46:31
distinct forms of influenza viruses. You have
46:33
the H17, H18, which are
46:35
very distinct genetically and they bind
46:37
to different receptor. And then these
46:40
HN92-like viruses, which they say the
46:42
simplest explanation is that it came
46:44
from a bird into a bat
46:46
and now it's established in a
46:48
bat. So, if I were a bat,
46:50
I would start working on vaccines. And
46:53
stay away from the birds. Stay away
46:55
from birds. Do birds
46:57
and bats ever mix? They
47:01
must because, you know, the flyway
47:04
from all of central and western
47:07
Africa goes up through the Nile
47:10
River. So, each and there's
47:12
no water anywhere else. Right. So,
47:16
well, the late Max Don't
47:40
know. All right. So, this paper is going to look
47:42
at this H is bat H9N2
47:45
virus and
47:47
try and know if it's a threat to people
47:50
as far as we can know. Right. Because
47:52
this is a, this is
47:54
a familiar, kind of familiar looking flu virus.
47:56
And it appears to come from birds into
47:58
a mammal. That's kind of the
48:01
pattern you look for for a new pandemic
48:03
flu virus. And this
48:05
one binds Alpha three thousand, two,
48:07
Three Selleck acids, which is what
48:09
Avian Influenza viruses typically do right?
48:11
So they're gonna do a number
48:13
of experiments now. First one, they
48:15
look at a P. H. In
48:18
activation of the virus
48:20
and basically incubating virus
48:22
is it. A
48:24
range of Ph is ah and with
48:27
a signed. His says
48:29
this is Gibson Fruit bat virus.
48:32
The. School aged nine and two. Is.
48:35
Has. Resistance to an
48:37
activation at a ph of similar
48:39
to that of of it's human
48:41
influenza virus the South's P. H
48:44
resistance of influenza viruses His tracks
48:46
with the passage in this city
48:48
and to his miscibility and the.
48:51
Resistance pattern of this virus to ph
48:53
is similar to that of human versus.
48:55
So. That's kind of interesting. Say
49:00
look at the Neuraminidase. Of
49:03
this virus now the Neuraminidase.
49:06
Is. A enzyme on the serfs
49:08
to the virus particles who's function
49:10
in most influence versus to cut
49:12
sale a cast from proteins to
49:14
allow the virus to spread after
49:17
it's release themselves. And.
49:19
The ignoramuses of age. Of
49:22
eight seventeen and ten at age eighteen and
49:24
eleventh is does not cut sale a gas
49:26
it isn't have what we call say our
49:28
days. Cutting. Off sale
49:31
at acid activity. But. This
49:33
one does this age two and. A
49:35
H nine and two from Egyptian
49:37
Fruit Bats does have say our
49:39
days activity so. And as.
49:42
Makes sense because if you bind ace assure a
49:44
say alec assets you have to have and
49:46
your minutes to cut it off. otherwise the virus
49:48
that's made will stick to cells wants to
49:50
try to stay. right? And the
49:52
other, the other bad flu viruses probably
49:55
don't need that because they're not using
49:57
that receptor out for using a protean
49:59
A receptors. right? I'm.
50:02
You. Know why? Why viruses like
50:04
that don't need some The catalyst their receptors
50:07
is unknown but know your poliovirus doesn't have
50:09
anything to cut it off of the poliovirus.
50:11
We sept I guess lad an issue Rayo.
50:14
Must. Not be an issue. Or
50:17
a so. These.
50:21
Is that he? We know the sequence. Of
50:24
them. The Am. The
50:27
he was glutenin of this virus and
50:29
they said previously people showed that this
50:31
him a gluten and has of the
50:33
receptor binding residues typical of those. They.
50:35
Chased By now says to Three
50:37
Links Sale Agassiz and they just.
50:40
Do. More. Studies on
50:42
binding to different sugars and
50:44
confirm that this. Receptive.
50:47
Specificity of this H nine. He was
50:49
goodness. Similar to avian viruses set to
50:52
are found in North America. There it's
50:54
a the alpha to three lengths. I
50:56
alec acids are common to birds and
50:59
the alpha to six months. I alec
51:01
ask for more common to humans. So
51:03
normally you see a shift from alpha
51:05
to three to alpha to six and
51:08
going from birds to mammals, but these
51:10
viruses don't seem to have had to
51:12
make that shift. They're still alpha to
51:15
three avian style bindings, but they're obviously.
51:17
Infecting mammals. night. I.
51:20
See never going to some insects and experiments.
51:23
And by the way I
51:25
love the just that this
51:27
this is a are fully
51:29
modern interesting important paper that's
51:31
like. Mostly. Classical Fire
51:33
allergy is amazing. Could have done these
51:35
experiments thirty years ago if you'd have.
51:37
If you've known to look for this
51:40
wire fence, Sisters are a very good.
51:42
I think this this underscores that we
51:44
still need to do certain kinds of
51:46
experiments. Yeah, So
51:49
they make They want to know how
51:51
these viruses reproduce in humans. Cel coaches
51:53
who they make. A air
51:56
liquid interface coaches of Human Bronco
51:58
Frankie ill and lungs. It's
52:00
a with that his his. You
52:02
tube take Brown Killer human lungs are
52:05
his lung cells from people's You played
52:07
them on a membrane. And
52:09
them. Then you take. The.
52:12
Membrane is is sub sub banned it in
52:14
the cell culture this others medium underneath it
52:16
and then the top is exposed to air
52:18
and and the cells like being in air
52:20
because that's what they do. we know oneself
52:22
spare loves us are they differentiate the all
52:24
the right cell types of course as was
52:26
cool air liquid as liquid underneath gives of
52:29
nutrition and then the air. They're. Like
52:31
ah finally something the breeze. And
52:35
an insect them with the states
52:37
nine and two and they also and
52:39
sex them with an H five and
52:41
one and a A. H
52:44
Nine and Two as representatives in a
52:46
human does two thousand and nine. H
52:48
One N One Pandemic Virus as a
52:50
representative Human fires right. So
52:54
as a human virus replicates really well
52:56
in these human cells as you might
52:58
expect with all the other viruses of
53:00
bad words and replicate the lower cells
53:03
as well as the ones from avian.
53:05
Sources: So this is what
53:07
you would expect. For
53:10
a human versus a bad were a
53:12
bird virus. So. This is called
53:14
ex vivo replication of physics is doing
53:16
in cells and culture so that's a
53:19
good word. We're using this in the
53:21
textbook. With you know there's
53:23
in Vivo in vitro and then his
53:25
Ex Vivo and Xv trucks and and
53:27
of this X be true. But.
53:29
Ex Vivo is not an animal, but it's
53:32
in cells and culture. In.
53:35
Cells it's in primaries cells I felt
53:37
for us so these are not pass
53:39
or take outlines if there's ex vivo
53:41
just taken out of the out of
53:43
a hostess race. So you may wonder
53:45
how you get bronchial and lung cells
53:47
Some patience. Of
53:49
people have bits of their lung taken out
53:51
all the time and their bronchitis so those
53:53
are those are available am. Okay,
53:57
Next. They look at. Alveolar.
54:00
epithelial cells. So the alveoli are
54:02
the cells lining the alveoli, duh,
54:05
all the way down in the
54:07
lung where the air exchange
54:09
occurs from the air
54:11
into the blood. And
54:14
so these are called primary human
54:16
alveolar epithelial cells. And the
54:19
avian virus, they say
54:21
there's not much difference in titers among
54:23
all of these except for the H5N1. So they're
54:25
all replicating
54:28
similarly in those cells. And
54:32
that's interesting because that's
54:34
where humans have most of their alpha-2,3-linked
54:36
sialic acid way down in the bronchi
54:38
and the alveoli. So
54:40
maybe that's part of the reason for that. So
54:44
then they look at what cytokines
54:46
are induced by these viruses
54:48
when they infect cells. And why is that interesting? Well,
54:50
you know, many of
54:52
these highly pathogenic viruses induce a cytokine
54:54
storm in people, and that's part
54:57
of the severe pathogenesis. So they want
54:59
to say, can we learn anything from
55:01
this? And they say the
55:03
H5N1 induced the highest levels
55:06
of cytokine mRNAs, cytokine and
55:08
chemokines. And the bat
55:10
Egypt had the least mRNA
55:13
encoding chemokines and cytokines.
55:15
So the H5N1s, when
55:17
they infect people, they cause cytokine storms.
55:20
That's the basis of
55:22
severe disease in many individuals. So
55:25
this is saying that that bat virus isn't
55:27
there yet. Right?
55:30
Which is good news. It's good news. Now,
55:33
how about pathogenicity? We're going to
55:35
look at two different hosts for
55:38
this virus, mice and ferrets. And
55:41
remember, mice lie,
55:44
monkeys exaggerate, and ferrets are not
55:47
humans. Right. Which
55:49
just tells you that mouse and animal
55:51
models, you've got to be careful about
55:53
them. So they inoculate
55:55
mice with the bat virus and
55:58
also a... avian
56:00
H9N2. So it's
56:02
another H9N2 but it's more
56:08
virulent than the duck virus.
56:10
It caused more weight loss
56:13
and more virus reproduction in
56:15
the lungs. And
56:18
they confirmed that by
56:20
immunostaining lung sections with antibody to
56:23
the viral nucleoprotein
56:25
and you can see diffuse replication
56:27
throughout the lung. So that's
56:29
interesting that the bat virus is more... And
56:32
at higher titers the bat virus kills
56:34
the mice, whereas
56:37
the duck virus does not. That's
56:39
right. They met human
56:41
endpoints at doses
56:43
of 10,000 and above
56:45
EID 50. But
56:51
we don't know what that means because these are mice.
56:53
These are mice, yes. But
56:56
that's what we have. But it's a mammalian
56:58
model that is straightforward
57:00
to use and you took this virus
57:02
from bats and you put it in
57:05
mice and the mice die at the
57:07
reasonable inocula of
57:09
this virus and that's something to
57:13
look out for. But the ferret
57:15
model gives you, according to WHO, that
57:17
what happens in ferrets is important for
57:19
pandemic risk assessment, right? So
57:21
they do some ferret transmission studies.
57:25
So they put, you know, they'll infect the
57:27
ferret and put it in the same cage
57:29
as another ferret and see if the
57:31
virus is transmitted. So that would be contact transmission
57:34
because, you know, ferrets can't resist touching
57:36
each other. And
57:38
then they put ferrets in a separate
57:41
cage, uninfected ferrets in a separate cage,
57:43
who would need to have aerosol or
57:45
respiratory droplet driven transmission and
57:48
see if the recipient gets it. And that would
57:50
be a more likely,
57:52
a more reasonable model for human
57:54
transmission. Well, it's a more
57:57
reasonable model for human transmission in
57:59
public. Whereas the direct contact
58:01
is more like a household. Humans
58:04
contact each other? So
58:06
I've heard. Okay. Yeah,
58:11
I don't even shake hands anymore. No, right. So
58:18
they infect ferrets with either the
58:20
bat H2, H9N2 or the duck
58:22
H9N2. They
58:26
measure the virus in the nasal washes. They
58:29
say both viruses called
58:31
mild clinical symptoms in
58:33
signs in infected
58:35
animals. Right. This is a sign. The
58:37
symptom is very, very mild. Like the
58:40
weight loss is not noticeable
58:42
at all. They see
58:44
maybe a slight decrease
58:46
in body temperature. And
58:48
I mean, these ferrets are fine. Ferrets
58:53
have symptoms, but they can't tell you about
58:55
them. So we don't know what they would
58:57
be. So we measure signs in them. The
59:01
bat H9N2 transmitted
59:03
to contact ferrets by
59:06
two days, but the duck H9N2 did
59:08
not. Right. And
59:10
the bat one transmitted both
59:12
with direct contact and airborne
59:14
contact. Very interesting. Yes. Right.
59:16
So that is a little
59:20
bit concerning, because as
59:22
they say later, well, we'll get
59:25
to that in the discussion. The WHO looks
59:27
at ferretransmission as an indicator for
59:30
pandemic threat. They
59:33
took these animals apart after the
59:35
experiment and looked for virus in different
59:38
tissues. They could find it in
59:40
the lung and the nasal turbinate. It
59:42
turbinated initially at three days. And at five days,
59:44
they find trachea brain in addition.
59:49
And they also did immunostaining
59:51
to confirm these findings.
59:55
They also looked at, this
59:58
is a new one, replication. and
1:00:00
transmission in mallard ducks, yes.
1:00:04
Hmm. So, the infect
1:00:06
birds, with
1:00:08
both viruses, the bat H9 and
1:00:10
the mallard duck
1:00:12
H9, no clinical
1:00:14
symptoms for two weeks. The
1:00:17
bat virus did not replicate in
1:00:19
the ducks. They got no
1:00:22
virus out, no seroconversion, but
1:00:24
the duck virus did replicate.
1:00:26
It was found in cloacal
1:00:29
swabs. That's the other end
1:00:31
of the bird. Yes. Right?
1:00:34
You know, in the bat,
1:00:36
it's a rectal swab. So, in a duck,
1:00:38
it's a cloacal swab, right? Because ducks have
1:00:41
one hole for everything. There
1:00:43
you go. Is that right? Yeah.
1:00:46
So, that's for peeing, pooping, and reproduction. It's
1:00:48
all through the cloaca. So, would that be
1:00:50
like one hole to rule them all? Yes.
1:00:54
Indeed. Dixon, you got
1:00:57
that cultural reference, didn't you? Pop
1:01:00
cultural reference. Yeah, yeah, yeah. All
1:01:02
right. So, it's interesting. So,
1:01:04
the duck virus replicates and ducks, the bat
1:01:06
virus does not. And
1:01:08
that's the story here. Right. So,
1:01:12
let's just chat a little bit more. The
1:01:15
idea, again, that
1:01:17
this virus most likely came to
1:01:19
a bat from birds, perhaps, perhaps
1:01:22
ducks. But H9N2
1:01:25
in general, they
1:01:27
say the H9N2 viruses
1:01:29
became established in land-based poultry in the
1:01:31
1990s. And
1:01:36
many isolates have been taken, which
1:01:38
they, and these viruses taken
1:01:41
from land-based poultry,
1:01:43
these H9N2s, have
1:01:45
an amino acid change in the hemagglutinin, which
1:01:49
allows the hemagglutinin to bind
1:01:52
alpha-2-6-syallic acids. So,
1:01:54
it's a signature for human receptor
1:01:56
specificity. Remember, the avian hemagglutinin
1:01:58
is bind. alpha-2,3-syllic
1:02:01
acids, the humans
1:02:03
alpha-2,6. So these viruses
1:02:05
from chikens, these H9N2 viruses
1:02:07
from chikens, have human receptor
1:02:10
binding specificity. Are
1:02:12
there any non-land-based poultry? Poultry?
1:02:16
No, I don't know. Poultry,
1:02:18
I think, is domesticated birds, right? I
1:02:21
don't know. What is poultry? What
1:02:23
is poultry? So many
1:02:26
good questions. Poultry is domesticated
1:02:28
birds kept by humans, yes.
1:02:30
Bingo. So
1:02:33
they're all land-based. They're
1:02:35
all land-based, yes. Well, a duck
1:02:37
is a waterfowl. It
1:02:40
is. And in
1:02:42
China, they raise them in ponds. Yeah.
1:02:45
In other words, to assess whether or
1:02:47
not the mallard ducks actually were suffering
1:02:50
or not from the infection, they should have
1:02:52
sent them to a correct doctor. Yes,
1:02:54
of course. Correct duck. No, they
1:02:56
should quack them open and look. They should quack them open and look.
1:02:58
I like that. Exactly. I
1:03:01
like that very much. All right. So
1:03:06
the bad viruses that the
1:03:08
bad H9N2 that we've been talking about in
1:03:11
this paper has
1:03:14
a glutamine at amino acid 226
1:03:16
of HA, which is a signature
1:03:18
of alpha-2,3-cylic acid binding. The human
1:03:21
alpha-2,6-binding HA's have a leucine at
1:03:23
226. So you can sequence
1:03:25
it and know immediately what the binding
1:03:27
is going to be. And consistent
1:03:30
with that, the bad H9N2
1:03:32
binds mainly to alpha-2,3-linked sugars.
1:03:35
But that's one amino acid change away
1:03:37
from being able to bind to the
1:03:40
other. Yeah. Yeah, so it's one amino
1:03:42
acid change. I don't understand why the
1:03:44
chicken H9N2s have all the human signature
1:03:48
in them. I'm not quite sure. Maybe we'll
1:03:50
ask Robert Webby that. Yeah. Is
1:03:52
that his name, Robert or Richard? Richard.
1:03:56
Thank you very much, Dixon. Thank you, Richard Webby.
1:04:01
Okay, so they say little brown
1:04:03
bats, myotis
1:04:07
lucifugus, are widely
1:04:09
throughout North America. They have both alpha-2,3
1:04:11
and alpha-2,6 salic acid throughout their respiratory
1:04:13
tract. So this makes sense that this
1:04:15
virus can reproduce in bats, right? And
1:04:19
they say there's no selection for
1:04:21
alpha-2,6 because bats have both. So if you
1:04:23
already got a virus with alpha-2,3, it's not
1:04:25
going to change to alpha-2,6 unless there's a
1:04:27
fitness advantage, and apparently there is not. So
1:04:32
these viruses, these H9N2 bat
1:04:34
viruses have avian-like HA receptor
1:04:36
signatures, and they say that
1:04:39
replication in primary human cells
1:04:42
are also avian-like. They don't reset.
1:04:44
They're low replication compared to the
1:04:46
human viruses, which replicate the
1:04:49
higher titers.
1:04:51
But when
1:04:53
you go down into the alveoli,
1:04:57
there's a little difference between
1:04:59
the replication, where there's alpha-2,3, mostly
1:05:02
salic acid. So that's interesting. All
1:05:06
right, so what else here? This
1:05:08
says here, the robust transmission of this
1:05:10
virus to animals,
1:05:12
ferrets, does imply an elevated risk
1:05:14
to human health. The
1:05:17
ability to transmit between ferrets is
1:05:19
a highly weighted element in the
1:05:22
WHO's tool for influenza pandemic risk
1:05:24
assessment. So
1:05:26
that's part of the... And the
1:05:29
influenza risk assessment tool the CDC uses,
1:05:31
which I assume is very similar. It
1:05:34
has different acronyms. Yes, so you can use
1:05:37
the TIPRA or the IRAT, but... Oh
1:05:39
my gosh, so many acronyms. Oh,
1:05:43
if you interact with any government agency, it
1:05:45
just gets completely out of control. That's true.
1:05:49
Why do they like acronyms? Because they've got
1:05:51
all these programs that have names and they
1:05:54
have to abbreviate them because they... Why
1:05:56
do we have jargon? I mean, why do we refer to
1:05:58
RNA and DNA? Yeah, yeah, yeah.
1:06:00
And, you know, giving the whole name is because...
1:06:02
It saves time. It saves time. We speak in
1:06:05
a shorthand and... But it... ...people in the policy
1:06:07
world do the same thing. Yes,
1:06:09
but then if somebody needs to communicate
1:06:11
outside of that sphere, it
1:06:13
becomes very alienating. So,
1:06:15
you know, like, here, you mentioned
1:06:18
a term before, Vince, use CTL. Ah,
1:06:20
yes. The cytotoxic lymphocytes.
1:06:22
The lymphocytes, right. If you
1:06:24
just... but it takes longer. Yep.
1:06:27
That's all. I should have said cytotoxic T
1:06:29
lymphocytes. Ah, because we are trying to explain
1:06:31
to the public. Yeah. Don't
1:06:34
worry about it. People outside of a royal machine. I
1:06:36
say it that way all the time. Yeah.
1:06:38
The conclusion here is that the
1:06:42
phenotypes of this bat H9N2
1:06:44
virus has some phenotypes
1:06:46
of avian viruses, some with human. They
1:06:49
say this mix makes it difficult to
1:06:51
assess the pandemic risk
1:06:54
of this virus. They say we
1:06:57
should, they say, further
1:07:00
investigating the abundance and nature of
1:07:02
influenza viruses in bats in comparison with
1:07:04
other avian viruses appears
1:07:06
prudent. Yes. Which
1:07:08
I would agree. The other thing... And
1:07:11
excluding bats from contact
1:07:13
with farm animals, I think, would be
1:07:16
prudent. I would be hard to do. Yeah.
1:07:19
Imagine how many people are
1:07:21
conducting surveys with
1:07:24
mist nets to catch bats, to tag
1:07:26
them and release them. How
1:07:28
many of them are carriers for influenza viruses?
1:07:30
I mean, you know, there's plenty
1:07:32
of opportunities for the bats and humans to come in
1:07:35
contact with each other as well. Well,
1:07:37
I don't know how many people are actually doing that,
1:07:39
Dixon. I think a lot of
1:07:41
people are. I really do. Are
1:07:44
you advocating no sampling, no wildlife sampling?
1:07:46
Not at all. But that just creates
1:07:49
an opportunity for people
1:07:51
and bats to come together. I would hope that
1:07:53
the people... And speed workers. Speed
1:07:55
workers. Yes. Okay. So
1:07:58
Yeah, I would hope that the people who are doing the sampling... A bad
1:08:00
for other scientific purposes. Are very careful
1:08:02
about this sort of thing. I mean,
1:08:04
not just because a flu viruses, but
1:08:06
because of rabies And because of Verona
1:08:09
viruses. I would
1:08:11
be much more concerned about people who
1:08:13
have less. Less.
1:08:16
Training: Who might accidentally contact?
1:08:18
Bats Spelunkers You mentioned Anybody
1:08:20
who works in addicts or
1:08:22
around structures were bats. My
1:08:24
Proust: Yeah.
1:08:28
But. That's not. that's a lot of people to your
1:08:30
point India and lot of people in contact with.
1:08:32
It's a new said. Present. Contact
1:08:34
between Batson. Wild.
1:08:37
Animals I know. I said prevent contact
1:08:39
between bats and farm animals. A farm
1:08:41
animals who they're they're use as you
1:08:43
have to keep the animals indoor space.
1:08:45
Yes, But. Bats can fly
1:08:47
indoors race they can drum. And.
1:08:50
That is that leave us story and it's
1:08:52
the but it's my I mean my concern
1:08:54
here would be as these bats are in
1:08:57
contact with pigs and you get this virus
1:08:59
going into pigs than maybe that's the intermediate
1:09:01
host. Or. Okay,
1:09:04
that's it. Let's do some email. Have
1:09:07
club. He's. You know, dixon last week
1:09:09
we didn't all email episode. I am sorry
1:09:11
I missed. The. Our was fund
1:09:13
was me, allen and Brin. Or
1:09:16
that doesn't them. I didn't want to
1:09:18
step one of the bodies are was
1:09:20
snowing on earth of of you would
1:09:23
know talented. you take the first one
1:09:25
please. Sure Braden Rights! Thank you for
1:09:27
reading an answering my question. How check
1:09:29
out the Cancers Know Mix project to
1:09:31
see if there's a way to minimize
1:09:33
my risk of dying from kept pancreatic
1:09:35
cancer. I think it was the email
1:09:37
after mine. The talked about comment threads
1:09:39
project that I did to spiff up
1:09:41
my Cv for grad school applications was
1:09:43
about Motor Sport Twitter. Basically.
1:09:45
Reading the comment threads and using grounded
1:09:47
siri methods to analyze at all. I've.
1:09:50
Also been part of a few isa
1:09:52
tearing what's app groups in my home
1:09:55
town for the Path last several years,
1:09:57
ostensibly to promote my events. These
1:09:59
are hard. The ads for Rfk Jr.
1:10:01
Sand I'm in disinformation. My posts
1:10:04
regularly go like. Sorry.
1:10:06
To be the science buzz kill. but. For.
1:10:08
Example and allopathic doctor is better
1:10:11
play with place to treat your
1:10:13
spider bite than an aroma therapists
1:10:15
Wilde areas peer reviewed evidence to
1:10:17
support that herbal supplement Helping her
1:10:19
supplements helping cancer patients. Ask
1:10:22
your oncologist about drug drug interactions
1:10:24
before using As/ivor Mack and Cure
1:10:26
is Rosacea because that's a parasitic
1:10:28
infection, but it isn't effective Against
1:10:30
Proven: Even though I'm sorry for
1:10:32
her and her family that Jackie
1:10:34
Stone header medical license revoked for
1:10:36
prescribing it. Comes. Along
1:10:38
those lines, I stay in
1:10:41
the groups because I've received feedback in
1:10:43
private messages that people appreciate someone speaking
1:10:45
up for common sense. If
1:10:47
you're man wants to effect change in
1:10:50
people's minds, he can join a similar
1:10:52
group and be as civil, compassionate, and
1:10:54
calm as possible. Randoms.
1:10:56
Yelling on to internet don't
1:10:58
change people's minds. People we
1:11:00
know are far more credible.
1:11:03
People. We know are far more credible than
1:11:05
some guy in a lab coat on the news
1:11:07
or someone who trolls us on social media. That's.
1:11:10
Why your more credible to me than Rfk
1:11:12
Jr who I've only ever heard stories about.
1:11:14
I. Like to think that during the recent
1:11:16
polio outbreak in Harare, some people from the
1:11:19
group. Allow. Their kids to
1:11:21
get Opie the update vaccines because I
1:11:23
spent two days explaining from knowledge gained
1:11:25
on with the risks and relative risks
1:11:27
and benefits of vaccines and that if
1:11:29
they could get ip the from their
1:11:31
private doctor that was the best option.
1:11:34
followed by getting Opie V from W
1:11:36
Oh people who went to the school.
1:11:38
And. Natural polio infection brought up the
1:11:40
rear with side effects like a lifelong
1:11:42
disabling paralysis living inside an iron lung
1:11:45
and death. I included
1:11:47
a list of things like. Quote.
1:11:49
Feed your kid anti inflammatory foods to
1:11:51
keep the or their immune systems focused
1:11:54
on the task at hand and. Book
1:11:57
an appointment with a Reiki healer for after
1:11:59
the vaccine. appointment to fill them up with good
1:12:01
energy, in the hopes that
1:12:03
having a possibly psychosomatic toolkit to
1:12:06
minimize ill effects would help them overcome
1:12:08
their vaccine hesitancy. Yes, taking
1:12:10
my stack of peer-reviewed research about
1:12:12
Russian-sponsored anti-vax disinformation around to beat
1:12:15
the sense into them would have
1:12:17
been more satisfying, but it's possible
1:12:19
that a few parents consented to
1:12:21
their kids receiving an OPV booster
1:12:23
with a Reiki healing chaser because they knew
1:12:25
me and I could speak their language. Have
1:12:28
a great day and keep up the good work, Braden. Cool.
1:12:32
What is Reiki healer?
1:12:34
Reiki, I think, is that the one
1:12:36
where they place warm stones on the
1:12:38
body along chakras or
1:12:40
something? I
1:12:44
gather it's a quite
1:12:46
innocuous alternative
1:12:49
therapy thing that if it makes you
1:12:51
feel good, fine. Uses
1:12:54
gentle touch and placement to heal
1:12:56
you. Sure. Okay. Do
1:13:00
you think, Alan, that the Russians sponsor
1:13:03
anti-vax disinformation in the US? We
1:13:05
know that. We do. Yeah,
1:13:07
that's been documented that
1:13:11
one of the many aspects of
1:13:13
the Russian disinformation campaigns on social
1:13:15
media was built around
1:13:18
sewing discord on issues including
1:13:20
vaccines. Okay. Dixon,
1:13:23
can you take the next one, please? I
1:13:26
would be more than happy to. Bryce
1:13:30
writes, hi, this week in
1:13:32
virology team. My interest
1:13:34
in virology has been growing while watching your
1:13:36
podcast for the past few weeks and while
1:13:38
taking a virology course class, BI115
1:13:41
at Caltech this term. It
1:13:44
has been fascinating to learn about the ways
1:13:46
the immune system can combat viral infections and
1:13:49
the different treatment and vaccination approaches that
1:13:51
have been tried and used for fighting
1:13:53
different types of viruses. One
1:13:55
thing that particularly piqued my
1:13:57
interest, discussed during your podcast,
1:14:00
was the additional roles of B
1:14:02
cells in combating viral infections beyond
1:14:04
producing antibodies. I had
1:14:06
a couple of questions related to some of the
1:14:08
podcast episodes that you have put out over the
1:14:10
past few weeks. On
1:14:13
Twiv 1103, you talk about two
1:14:15
protein substitutions boosting the expression and
1:14:18
stability of the spike protein in
1:14:20
many coronaviruses. A model
1:14:22
came out of Bill Clemens' lab
1:14:24
at Caltech called IMPROVE for
1:14:27
predicting the expression of integral membrane proteins
1:14:29
in E. coli based on their sequences.
1:14:33
Are there similar computational models to
1:14:35
IMPROVE that have been used for
1:14:37
boosting the expression of viral envelope
1:14:39
proteins like spike proteins discussed? On
1:14:42
Twiv 1099, it
1:14:45
was mentioned that it
1:14:48
is rare to find two identical genomes of
1:14:50
hepatitis C virus, even in the
1:14:52
same patient. What is
1:14:54
it about this virus that allows its genome
1:14:56
and the associated proteins to be so tolerant
1:14:59
to mutation? Would such
1:15:01
a high mutation rate not lead to
1:15:03
many dysfunctional viruses being produced? Thank
1:15:06
you for all you have taught me through your
1:15:08
podcast and for taking the time to look at
1:15:10
my questions. Best wishes, Brace.
1:15:14
Very thoughtful and
1:15:17
interesting letter from
1:15:19
a newbie student of virology that has some
1:15:22
pretty deep questions for a person
1:15:24
that's just recently been exposed, does
1:15:26
that say? I don't know about
1:15:30
models to boost
1:15:33
production of envelope proteins. I'm not
1:15:35
aware of any of those. I know that when we talked
1:15:37
to Jason McClellan in
1:15:40
Texas, he talked about ways to design
1:15:44
vaccines which include adding prolines
1:15:46
but also adding disulfide
1:15:48
bonds and trying to
1:15:50
fill in pockets of a ton of molecules
1:15:52
that lead to conformational change and so forth.
1:15:56
I'm not aware. Do you know of any Allen models?
1:15:58
No, it hasn't. hasn't come up, but that doesn't
1:16:01
mean much. Yeah. To
1:16:04
Jason would know, because
1:16:06
he might use them. Yeah. And
1:16:09
the reason hep C,
1:16:11
it just,
1:16:14
so it's very interesting. The
1:16:17
mutation rates for RNA viruses are all
1:16:20
pretty similar in terms of the error
1:16:22
frequency of the polymerase, with the exception
1:16:24
of the coronaviruses, which have error correction.
1:16:27
So hep C is just as error-prone
1:16:29
as poliovirus. And
1:16:34
so if you track poliovirus
1:16:36
as it goes from the mouth when
1:16:38
you ingest it to the feces, in
1:16:41
about five days it changes 5% of the genome. And
1:16:45
so it varies just
1:16:48
as much as hepatitis C. And
1:16:50
you ask, would such a high mutation rate lead
1:16:53
to many dysfunctional viruses? Yeah,
1:16:56
it could. And they would be removed by
1:16:58
purifying selection, right? Just
1:17:00
like ORF8, no. If
1:17:03
it were bad, it would be removed. Yeah.
1:17:05
A lot of the genomes that get produced
1:17:07
in, well, in any viral infection, but in
1:17:09
an RNA viral infection in particular, are going
1:17:11
to be broken.
1:17:14
And if they get packaged,
1:17:16
they'll get sent out. And that's a particle
1:17:18
that won't initiate a productive infection. But
1:17:21
the virus is producing so many copies
1:17:24
that some of them are going to be fine. The
1:17:28
other part of this question is, what is it
1:17:30
about the virus that allows the genome and proteins
1:17:32
to be so tolerant? So the protein, that's the
1:17:34
key. Many viral proteins are
1:17:36
more tolerant than others. Like the spike
1:17:38
of SARS-CoV-2 can tolerate
1:17:41
many amino acid changes, right? But
1:17:44
what is it? The spike of measles virus
1:17:46
is less tolerant. We did
1:17:48
that study, remember, which we likened to
1:17:50
the airplanes that came back where were
1:17:53
the bullet holes, right? They reinforced those
1:17:55
parts of the wing. So
1:17:58
measles. It
1:18:01
must be a structural thing, right?
1:18:06
All right, Terry writes, your
1:18:08
videos not only got me through my
1:18:10
own virology course at University of Alaska
1:18:13
Fairbanks, but you have inspired me to
1:18:15
go into virology and eventually work in
1:18:17
biosecurity. I'm actually presenting
1:18:19
as an undergraduate at the AAAS
1:18:21
Regional Conference in San Diego this
1:18:24
June on the boreal pox virus,
1:18:26
formerly known as Alaska pox. I
1:18:29
cannot thank you enough for the inspiration and giving me
1:18:31
the courage to follow through. You are one of the
1:18:33
authors of my textbook that I cherish, and I just
1:18:35
needed to say thank you for everything. Thank
1:18:38
you, Terry. We appreciate you. Thanks.
1:18:41
So many thanks. We
1:18:43
do love hearing stories of how we help
1:18:45
you. I
1:18:48
think we're back at the top with Alan, right? Back
1:18:50
to me. Anthony writes,
1:18:52
the cartoon image attachment in the
1:18:54
preceding email was posted on Facebook
1:18:56
as an example of the idiocy
1:18:59
slash lunacy of anti-vaxxers. I
1:19:01
thought it too ridiculous to be so,
1:19:03
but I found in the Chicago Tribune
1:19:05
article that the image had
1:19:07
been posted by one of the Trump delegates. This
1:19:11
is a cartoon of cattle waiting at
1:19:13
the slaughterhouse, and one of them is
1:19:16
complaining that one of the ones ahead of him is
1:19:18
not wearing his mask. And
1:19:21
obviously being that taking
1:19:24
SARS-CoV-2 seriously is
1:19:26
like being led to slaughter. Yeah,
1:19:29
that's pretty insane. Cartoon
1:19:32
was sent to me by a Hudson
1:19:34
County resident, an anti-vaxxer. I
1:19:36
was shocked that anyone would think this image
1:19:39
to be insightful or persuasive. If the individual
1:19:41
had recently arrived from some backwater or was
1:19:43
intellectually challenged, I'd not have given it a
1:19:45
thought. But this person grew up
1:19:48
in Queens, New York and had worked in China
1:19:50
for a major US financial publisher. Remember
1:19:53
Ionesco's Rhinoceros? Ionesco's
1:19:55
Rhinoceros? I'm
1:19:58
looking it up. So
1:20:00
it's flagged by Jean Yonesco.
1:20:03
Right. Oh, it's the theater of the
1:20:05
absurd. Indeed. Do
1:20:07
you know that, Dixon? I know the theater
1:20:10
of the absurd. I didn't realize that the particular
1:20:13
episode, Rhinoceros, was in it. Over the
1:20:15
course of three acts, the inhabitants of
1:20:17
a small French town turn into Rhinoceroses.
1:20:19
Ultimately, the only human who does not
1:20:22
succumb to this mass metamorphosis is the
1:20:24
central character,
1:20:27
blah, blah, blah. The play is often read
1:20:30
as a response and criticism to the sudden
1:20:32
upsurge of fascism and Nazism during the events
1:20:34
preceding World War II, and
1:20:37
explores themes of conformity, culture,
1:20:39
fascism, responsibility, logic, mass movements,
1:20:41
mob mentality, philosophy, and morality.
1:20:45
Okay? That's Rhinoceros. Rhinoceros.
1:20:47
Rhinoceros. Thank you, Anthony, for that reference. I'm
1:20:49
sorry I didn't get it. The real reason
1:20:51
he didn't convert to Rhinoceros was because he
1:20:53
didn't want to horn in. Right. By
1:20:58
the way, there seems to be
1:21:00
considerable intersection between anti-vax and hatred
1:21:02
of cars. That's interesting. The electric
1:21:04
car mania, I strongly suspect, to
1:21:07
be a facet of the Oedipus
1:21:09
complex. Removal of the internal combustion
1:21:11
engine is equated with castration and
1:21:13
perhaps EV sounds like ED. Gosh.
1:21:16
Okay. Hatred of electric cars,
1:21:19
maybe, is what you meant. Yeah, I think so.
1:21:22
Okay. Well, electric
1:21:25
cars have more thrust, so
1:21:27
think of that what you like. Oh
1:21:29
my gosh. Sorry, sorry. It's a family
1:21:31
show. Dixon, you're next. I know, I
1:21:33
know, I'm not sure I'm going to
1:21:35
go on. John writes,
1:21:37
Vincent and the Twiv team, based
1:21:40
on the comments of a few Twiv episodes ago
1:21:43
when H5N1 was repeatedly mentioned in the
1:21:45
news, I thought it would send along
1:21:47
a new map with data
1:21:49
updated to April 20th, 2024 of the confirmed
1:21:51
cases of wild birds infected with
1:21:56
AVN H5N1 influenza. The
1:21:59
map contains more... than 10,000 data points
1:22:01
and gives the location at the county
1:22:04
health department reporting level,
1:22:06
the species of bird infected, and the
1:22:08
strain of H5N1. Oh, that's
1:22:10
interesting. Well, I sent
1:22:12
in another map to you almost six months ago,
1:22:14
which you talked about on the air, but this
1:22:16
map is now complete and accounts for the extremely
1:22:19
rapid increase in case reporting. And
1:22:21
then it gives a link to that. Also,
1:22:23
we have now compiled the data on
1:22:25
mammals from the USDA Plant and Animal
1:22:27
Health Inspection Service, whose data
1:22:30
now confirms more than 200 domestic
1:22:32
and wild mammals that have died from AV and
1:22:34
H5N1. Here
1:22:37
is the map for that if you're interested. And it
1:22:39
gives the next link. I love the show.
1:22:42
That is an understatement as there is nothing else
1:22:44
like it out there. And I've
1:22:46
been listening and supporting since the beginning. You
1:22:49
should have a GIS scientist on one of those days
1:22:51
to talk about the difficulties in mapping
1:22:53
the spread of things like H5N1. That's
1:22:56
a great idea, which is a nightmare
1:22:58
map to map and keep
1:23:00
track of at the field level. You
1:23:03
know, there's no question
1:23:05
about this. And the
1:23:08
best thing I've seen so far for
1:23:10
something like this has been the
1:23:14
epidemic of opioid
1:23:16
overdose. I'll
1:23:18
send you the map of that. It's not a map,
1:23:20
actually. It's a single figure. But the
1:23:23
width of the figure at the particular
1:23:25
time of the year equals
1:23:27
the number of deaths from
1:23:29
opioid overdose. And it's
1:23:32
alarming to say the
1:23:34
least to see it visualized like that, because
1:23:36
you can envision how this thing
1:23:38
works. And it's still out
1:23:40
there. And it's still having its effects. I
1:23:44
don't know what to suggest about this, except the
1:23:46
more easy it is to see
1:23:48
what's happening, the more understanding there
1:23:50
will be. The maps
1:23:52
are amazing. Yeah. Yeah,
1:23:54
I mean, this is a great idea if
1:23:56
we can get an epidemiology GIS person
1:23:59
on. I would love that.
1:24:02
John, if you know someone. Or if
1:24:05
you are someone. John is
1:24:07
a lecturer in applied
1:24:09
mathematics and geographic information science. This
1:24:12
graphic is very small. That's John
1:24:16
Hopkins. GIS is, right? Yeah,
1:24:18
so geographic information science is GIS.
1:24:22
Actually, I know someone over at Hunter College
1:24:24
if you're interested. His name is Sean A.
1:24:26
Hearn. And we actually published
1:24:28
a paper once on the West Nile virus epidemic
1:24:31
because it was evolving. And
1:24:33
he's really very good at it. So
1:24:36
the first map, which is the H5N1 isolation,
1:24:39
is you click on each dot and
1:24:41
you get information about where it's
1:24:43
from. Just the way it should be. Oh my
1:24:45
gosh. Ohio, bald eagle.
1:24:48
February 28th, 7 p.m. Wow.
1:24:52
And then it's all over the U.S. Look,
1:24:54
except some places are sparser than others. But
1:24:56
that may just be a population issue. Yeah.
1:25:00
And then there's one of mammals, which is far
1:25:02
less, but let's click on the one in New
1:25:04
York. And that is
1:25:06
a red fox in Rhode
1:25:08
Island. This
1:25:11
is great. We will put links to this. You can
1:25:13
have fun. This is cool. With this.
1:25:16
The mammals seem to be north biased,
1:25:18
don't they? Maybe,
1:25:21
yeah. Maybe they're not looking in the south.
1:25:23
I don't know. Thank you, John.
1:25:25
That's very cool. All right. We
1:25:27
have another email, but we'll save it for Angela
1:25:29
because it's a vet question. Right. Which
1:25:33
now brings us to our picks. And
1:25:36
Dixon, what do you have for us?
1:25:38
Well, I have two of them. The
1:25:40
second one is a short pick, but it's
1:25:43
really worth watching, however. The
1:25:45
first one is a video produced
1:25:47
by NASA on
1:25:51
a theoretical journey that you could take
1:25:54
to the Andromeda Galaxy. And
1:25:57
there has been so much detail.
1:26:00
now that
1:26:02
the James Webb Space Telescope is in operation,
1:26:05
that you can actually go to various
1:26:07
parts of the Andromeda Nebula and
1:26:10
see what it would look like if you turned around
1:26:12
and looked back to the other way and saw what
1:26:14
our galaxy looks like from the Andromeda
1:26:17
Nebula. Well, the significance of all that
1:26:19
is that the Andromeda Nebula
1:26:21
is slowly but surely moving
1:26:24
towards our galaxy. And
1:26:28
that's the Andromeda Galaxy. What
1:26:30
did I say? You said Nebula but
1:26:33
it's... I'm sorry. I meant galaxy.
1:26:37
The thing that I was confused about in
1:26:39
the beginning of all of this a long
1:26:41
time ago was that why are some things
1:26:43
moving towards each other when Hubble says everything
1:26:45
is moving away from each other? Well, that's
1:26:48
true on a large scale but on a
1:26:50
small scale. You have these perturbations. So
1:26:52
in about 4.5 billion years from now,
1:26:55
and I'm sure everybody's out
1:26:57
there biting their fingernails worried about all this,
1:27:00
these two galaxies will join
1:27:02
and become one with
1:27:04
one another as it were. And
1:27:06
as I put it, we will become scrambled
1:27:08
eggs because the Andromeda Galaxy is more organized
1:27:14
and probably is heading towards us more
1:27:16
than we're heading toward it. But
1:27:20
it's amazing to think
1:27:22
about the galactic pressures
1:27:25
that are at work
1:27:27
for the gravity to be so
1:27:29
immense to include trillions
1:27:32
of stars from each of these
1:27:34
two galaxies. I
1:27:36
can't possibly imagine it
1:27:39
but you can actually watch
1:27:41
it actually happen before
1:27:43
your eyes. So
1:27:45
I thought that was a startling thing to
1:27:47
think about in the long term. But
1:27:49
in the short term, I thought this snippet
1:27:52
of the highest
1:27:55
jump ever recorded
1:27:57
by a human being, and it was
1:28:00
documented by this
1:28:02
guy jumps like
1:28:04
50. I forget
1:28:07
how quiet it is. It's a 12
1:28:10
and a half foot high. He's at the
1:28:12
top of the scale. You can't go higher than that because
1:28:14
they don't have a way to measure it. Well,
1:28:17
basketball hoop is 10 feet and he's two feet
1:28:20
on the rim. Yeah,
1:28:22
the thing is that you wonder
1:28:24
about things like this, whether they're actually
1:28:27
photoshopped or fake or something else. And
1:28:29
I don't think so. I've actually seen
1:28:31
this where he was doing several
1:28:35
practice jumps first and
1:28:37
they were all equally off
1:28:39
the charts. So that's just
1:28:41
for an enjoyment's sake. Very
1:28:44
cool. Those are my two picks. We
1:28:47
had some corrections from last week
1:28:49
for you about collisions and
1:28:51
black holes. What did I say? Oh,
1:28:53
yeah, we read some letters about... Great.
1:28:56
You mean I got roasted? Correcting
1:28:58
your astronomy. Yeah, no, you weren't
1:29:00
exactly roasted. It was astronomers
1:29:02
writing into. Oh, dear. But they said you
1:29:04
got most of it right. They were just
1:29:07
confused things. I got most of it right.
1:29:09
They said they love you anyway. You're
1:29:12
still a star to them. A
1:29:16
fading star, no, but no less. I'm
1:29:18
running out of hydrogen for God's sakes. Alan,
1:29:22
what do you have for us? I have
1:29:24
one pick but two links. One
1:29:28
is a gallery that
1:29:30
Nature put together about
1:29:32
what a scientist looks like. And
1:29:35
I love this thing. It's
1:29:38
so it's it's a bunch
1:29:40
of pictures. They got clearly
1:29:43
they got professional photographers or at least people
1:29:45
who could be professional photographers to do these
1:29:48
portraits. They're very well shot. And
1:29:51
I love the diversity
1:29:53
that it shows not just in
1:29:55
the appearances of the people, which
1:29:57
there's a lot of, but
1:29:59
also in the... the activities in which they're
1:30:01
engaging. So it's not a bunch of
1:30:03
people standing around in lab coats, some
1:30:06
of them are, but it's also not
1:30:08
just field scientists standing with a mountain
1:30:10
in the background, though some
1:30:12
of them are. It's just all
1:30:14
kinds of neat stuff that people
1:30:16
are doing that is scientific
1:30:18
research. You've got an astronomer looking into
1:30:21
a huge telescope, you've got somebody in
1:30:23
a greenhouse and somebody handling a snake
1:30:25
and somebody, you know, in a rainforest
1:30:27
and someone in the lab. I love
1:30:29
it. It's just really, it's
1:30:32
a great, I
1:30:35
think it's just a really good public outreach
1:30:37
effort for people to get their minds around
1:30:39
what science really entails.
1:30:42
And then they took this all a step
1:30:44
further, they have
1:30:46
put 50 of these photographs on public
1:30:49
display at bus stops in London. Oh,
1:30:52
cool. Like where you would normally see an
1:30:54
ad, there's one of these pictures of one
1:30:56
of these scientists explaining what
1:30:58
this person does. And I
1:31:00
think that's really cool. And
1:31:03
I would love to see them do that in more
1:31:05
cities. I know they have offices, nature has offices in
1:31:07
New York, so that seems like it ought to be
1:31:10
something they do, maybe elsewhere too. Wow.
1:31:16
Yeah, well, scientists look like everyone
1:31:18
else basically. They look like everybody else. They
1:31:20
do. They're doing all kinds of cool things.
1:31:22
They are everybody else. All
1:31:26
right. I have two picks
1:31:28
which relate to what's been happening this
1:31:30
week. At Columbia, which
1:31:32
is there have been protests, of course, and
1:31:35
on campus, which brings
1:31:38
you back to the 1960s, Dix and I
1:31:40
were talking about Mark
1:31:42
Rudd and Grayson Kirk
1:31:45
and the Students for a Democratic
1:31:47
Society. The SDS, or the
1:31:49
sodium dodeckel sulfate. Yeah, that's what I always
1:31:51
thought about it. That's right. Anyway,
1:31:55
there's one article in The Atlantic. I mean,
1:31:58
they're just views on the... on the protests, which
1:32:00
I think are very good. The
1:32:03
campus left occupation that broke higher
1:32:05
education by George Packer.
1:32:07
Elite colleges are now reaping the consequences
1:32:09
of promoting a pedagogy that trashed the
1:32:11
post-war ideal of
1:32:15
the liberal university. So
1:32:18
basically, liberal universities are supposed
1:32:20
to be places where you can say anything
1:32:22
you want. Where
1:32:24
else in the world can you do
1:32:26
that? You can't protest at many other
1:32:28
places. And
1:32:31
so now we see
1:32:33
reactions to that. He
1:32:35
says they started all in the 1960s with
1:32:37
the occupation of the president's office at
1:32:40
Columbia University. So
1:32:43
basically, it's the fault of the Boomers. Is
1:32:45
it? I don't know whose
1:32:47
fault it is, but that's how I see it.
1:32:50
Well, last night, they said the largest
1:32:53
protest ever on campus was
1:32:55
after the news leaked out that
1:32:58
Nixon had ordered the bombing of
1:33:00
Cambodia. And
1:33:02
McNamara said, we have not done that. And
1:33:04
then Nixon admits that we have done it.
1:33:07
And that triggered an enormous response
1:33:09
from students. The most
1:33:12
that ever, like 900 campuses, including
1:33:15
high schools and grade schools, everything, just
1:33:18
went crazy. I don't remember that event, actually. Well,
1:33:21
you notice that the protests are not just at Columbia. There
1:33:23
are many universities. There are many places. Because those are places
1:33:25
where you can. If you think about it, you can't just
1:33:28
go out on the street. Permit.
1:33:30
And if you don't have one, you're going to get arrested.
1:33:33
You can't do it in a building of a business. They're not
1:33:35
going to let you do that. So that
1:33:37
leaves campuses. And now this article
1:33:39
is arguing, now they're cracking
1:33:41
down against the thing that they think
1:33:44
they're promoting. So that's kind
1:33:46
of an interesting dichotomy. So
1:33:49
that's interesting to read. And then
1:33:51
my second one is an opinion by
1:33:54
John McWhorter, who's a Columbia professor. It's called,
1:33:56
I'm a Columbia professor. The protests on my
1:33:58
campus are not just. And
1:34:02
you know, there's a
1:34:04
photograph. So, when I went last
1:34:06
Wednesday, over
1:34:08
a week ago, right, the main gate was
1:34:11
closed. There were police with riot helmets there.
1:34:13
There was a line of people protesting outside.
1:34:16
And then inside, there was some kind
1:34:18
of demonstration. And
1:34:20
we had to go around to get
1:34:24
another gate. But that's all fine. On
1:34:26
Monday, they said, don't come at all.
1:34:28
Teach remotely by Zoom. And
1:34:31
then we went back this following Wednesday. I
1:34:35
think this is a good perspective
1:34:37
because he said he's arguing basically,
1:34:39
it's not peaceful. And
1:34:42
you're entitled to protest, but you're
1:34:44
not entitled to be anti-Semitic, for
1:34:46
example. That's not what protest is
1:34:48
about. But that's, he also
1:34:50
says that if these people had
1:34:53
been chanting anti-black slogans, they would have
1:34:55
been shouted down immediately by other students
1:34:57
and so forth. But I
1:34:59
think they're both interesting perspectives,
1:35:02
right? So
1:35:04
that's why people have sent them to
1:35:06
me, actually, in the course of the
1:35:08
week. So I thought maybe people
1:35:10
would be interested in what's going
1:35:12
on. I don't know what the solution is
1:35:14
when, you know, the
1:35:17
university itself cannot make
1:35:21
changes that they want, right? They
1:35:23
cannot end the conflict.
1:35:25
No. Right.
1:35:28
Someone else, but they were going to stay
1:35:30
there at Columbia until, you know,
1:35:33
it doesn't seem to be rational to
1:35:35
me, but I don't know. Anyway,
1:35:37
they're interesting. No, I can understand protesting
1:35:40
for the university to
1:35:42
divest investments from particular
1:35:45
things because that is something that is in
1:35:47
the university's power. Yeah.
1:35:51
That saying, you know, we're going to protest
1:35:53
until there's peace in the Middle East, that's
1:35:55
not really something that needs to
1:35:57
be fixed. In the 60s occupation, the demand for peace is not going to be
1:35:59
as good as it is. was to stop
1:36:01
Columbia stop investing in military research.
1:36:03
When I was in college there
1:36:05
was a whole raft of protests
1:36:07
around divestment from South Africa. And
1:36:11
divestment from companies that had significant presence
1:36:13
in South Africa and you
1:36:16
know that's the kind of thing that I
1:36:18
think makes sense whether
1:36:21
you agree with the cause or not but that's a
1:36:23
that's a kind of demand that you could make in
1:36:25
this context and it
1:36:28
would be reasonable. Well he mentions that in this
1:36:30
article as well that
1:36:33
the South African protests. Right. Yeah. Alright
1:36:35
we also have a listener pick from David.
1:36:38
Back in the 90s one of the highlights of
1:36:40
my video career was being able to record the
1:36:42
US Navy's Blue Angels at an
1:36:44
air show in Kalamazoo, Michigan but the
1:36:46
ground-based footage I got is nothing compared
1:36:49
to the visuals captured by the camera
1:36:51
affixed to the bottom of the team's
1:36:53
lead plane seen in this YouTube video
1:36:56
containing what amounts to their entire show
1:36:59
over San Francisco in October 2019. It
1:37:01
is both a thrilling demonstration of the
1:37:04
Blue Angels extraordinary flying skills as
1:37:06
well as a virtual overhead travelogue
1:37:08
of San Francisco region including such
1:37:10
landmarks as the Golden Gate Bridge
1:37:13
in Alcatraz. And while the
1:37:15
visuals are thrilling the soundtrack which is muted
1:37:17
engine noise is paradoxically soothing
1:37:19
being essentially a form of white noise.
1:37:21
If you don't have time to watch
1:37:23
the entire 45-minute program at least the
1:37:26
last 15 minutes contains some of the
1:37:28
best bits and he gives
1:37:30
a YouTube. It is a very cool video.
1:37:32
David is a micro TV video editor. Oh
1:37:35
wow. Who will be hearing this read
1:37:37
as he's editing this video on Saturday sometime.
1:37:39
Thank you David. Fabulous.
1:37:42
Yeah. That's it for Twiv 1109.
1:37:44
1109 as show
1:37:47
notes are at microbe.tv slash Twiv. If
1:37:49
you want to communicate with us for
1:37:51
any reason pick
1:37:55
a comment a question the email
1:37:57
is twiv at microbe.tv and
1:38:00
We would love to have your financial
1:38:02
support. It means that you enjoy what
1:38:04
we do and it also will help
1:38:06
us do more of it. You go
1:38:08
to microbe.tv slash contribute. Dixon
1:38:11
de Pomier is at
1:38:13
trickinella.org and thelivingriver.org. Thank
1:38:16
you, Dixon. Thank you, Vincent, and
1:38:18
thank you, Dan. It's not Daniel, whoever
1:38:20
I am. Alan,
1:38:23
Alan the dove. Yeah,
1:38:26
and how dare you speak out against war. Yeah,
1:38:29
that's a very good way to say it.
1:38:34
Alan Dove is at alandove.com
1:38:36
and turbidplaque.com. Thank you, Alan.
1:38:38
Thank you. It's always
1:38:41
a pleasure. I'm Vincent Raconiello. You can find me
1:38:43
at microbe.tv. I'd like
1:38:45
to thank the American Society for Virology
1:38:47
and the American Society
1:38:50
for Microbiology for their support of
1:38:52
Twiv, Ronald Jenkes for the music,
1:38:55
and Jolene for the timestamps. You've
1:38:58
been listening to This Week in Virology.
1:39:00
Thanks for joining us. We'll be back
1:39:02
next week. Another Twiv. This
1:39:04
is Virology. This is Virology.
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