How Herd Immunity Works

Herd immunity is an epidemiological concept that if enough people are inoculated against a disease the rest of us won’t get it. It’s been useful in holding back diseases like polio and measles, but we have vaccines for them. We don’t have one for Covid-19.

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Episode Transcript

Speaker 1 (00:01):
Welcome to Stuff. You should know a production of My
Heart Radios How Stuff Works. Hey, and welcome to the podcast.
I'm Josh Clark. There's Charles W Chuck Bryan over there,
and uh, it's just the two of us again. But
I'm getting used to it. How about you? I am.

(00:23):
I am sweating in our studio by myself, Like you're
nervous now. I'm hot because the studio is hot and
you know, I know we've been buzz marketing enough, but
the internet is only working in our studio for some reason.
And uh, I ate some of that spicy beef ramen

(00:43):
in this hot room. Yeah, that's a dangerous combo. I
didn't think to open the door, So I'm just like
sitting here pouring sweat out everywhere. Well here's the thing.
You could go totally dong out like Spartacus if you
wanted to, because you're the only one there. People have
been talking about dong out lately. To the movie crush page. Yeah,

(01:04):
well it's a pretty hilarious term. But just please put down,
like some newspaper or something on the chair before you
sit on the bare bottomed Okay. Oh, and by the way,
speaking of movie crush, you. I think this is going
to come out the day after your movie Crush Mini
Crush appearance next week. Yeah, I'm excited about it. Man,

(01:25):
I'm a little nervous. So No, it's gonna be great.
People are gonna love it. So if you don't listen
to the show, maybe listen to this one episode and
then forget about the show again. If you want always
stick around, maybe boost the numbers a tad. But it
was a lot of fun, and I think I think
people would want to hear your appearances. What I really

(01:45):
appreciated you having me on it was it was a
lot of fun. It was fun professional at hosting. Hey,
we turns out we know what we're doing here, don't
we don't? Uh? Speaking of which, I think we should
frontload this episode with a little bit of a c
o A Um. If you are a pretty hard line

(02:08):
anti vaxer, or if you believe in things like planned
demmi or that Bill Gates created the coronavirus for population control,
you may not want to listen to this because we're
gonna bring you hard and leaned facts, lean and mean,
depending on your point of view. I think that's a

(02:28):
good It's a good c O a. I think that
maybe you got rid of two of the hate mail
we're gonna get, so thank you for that. Yeah, we'll see.
I mean I think, uh, it just bears saying, just why, why,
why rile yourself all up? Just let's listen to your
echo chamber podcasts that validate what you think maybe or

(02:50):
or or or or calm down and just hear us
out and see what you think. Well, that's always a
you know, it's always an option. You know. So we're
not even talking necessarily just about vaccines or anti vaccines. Um,
it's almost like a side thing to this whole thing,

(03:11):
but it's definitely still, um, very much intertwined with it. Um,
we're talking about her can't or you can't not talk
about vaccines if you're going to talk about her immunity
right now, because with with her immunity, especially in the
twenty one century, there's basically two ways of getting there,
and one of them is a robust vaccination program. That's right.

(03:37):
And if you don't know what her immunity is, then um,
then you're probably just fine. You've been living under a
rock and you're not near any other humans or the internet.
You're still protected though that's right. Herd immunity those the
principle uh, sort of in its simplest form of safety
and numbers and if you have a lot of people
or enough people, because there's actual math involved to figuring

(03:58):
that out. It's not just a guess. If you have
enough people that are immune to a virus. Uh. And
it can be like you said, through vaccination or through
having lived through the disease and then having antibodies, then
the population is protected from that disease even if they
are an immune. That's that's the idea that so many

(04:20):
a certain threshold of people are immune that even people
that choose not to vaccinate can hop on that wagon, right. Um.
And it's not even like you hop on the wagon,
like you are on the wagon just by vulture being
alive in the society or culture. Right. So that's a
good point. Um. There's a really easy way of understanding
it that Molly Edmonds used in Um the House Stuff

(04:44):
Works episode Unheard Immunity that if you pretend you're at
a bowling alley and each person has their own lane,
and this is basically that bowling alley lane is like
there their bubble that they live in, their work their
home and everything, and they don't encounter anybody else. That's
kind of like Wally, But with bowling. If the first
person on lane one comes down with say the flu um,

(05:08):
he can very easily pass it on to the woman
in lane two. If she's not immune to the flu,
she will contract it and pass it on to the
person in lane three, and so on and so forth,
and it'll just keep going and eventually people will develop anybodies.
Some of those people will die, most will survive, uh,
and the flu will have a hard time getting through
that population a second time around. But if the woman

(05:33):
in lane two is already immunized to that flu strain,
say through like a vaccine or something, then it's not
going to transmit from the first guy in lane one
to her, or it's certainly not going to transmit beyond her.
So she's protected everybody in lanes three through ten just
by virtue of having been immune to that flu virus.

(05:55):
It's stopped with her, and that's the point of her immunity.
That's the whole that's the basis of the whole thing. Yeah,
And if we want to stick with bowling parlance, then
that means that that lady is bowling strikes. She's throwing
strikes strikes, not even seven ten splits, which she could
if she wanted to. That's how she is. Yeah, the
perfect game, right. I remember that dumb joke when I

(06:18):
was a little about You know, you learn the stupidest
jokes when you're a kid because they have to be
so dumb. A kid can understand him, I think, I
think so. But about the the guy who bowled a
three hundred and one and you're like, you can't bowl
a three d and one, Well, you can't bowl a
three hundred and lose, man. I know. That's how bad
it was, and that's how much it stuck with me.

(06:39):
Did you get that from highlights? I don't know where
I got that. It's pretty bad. It sounds like a
playground joke. I think so. But I think you beat
up in the playground even with that one. Yeah. So
let's talk about her community some more. We talked about
the two ways natural exposure and vaccinations, and if we're

(07:00):
going back pre vaccination and talking about human history. Um,
the hurt there was hert immunity, and it was I
guess the way to describe it as herd immunity. The
hard way. Um, people being exposed to the virus or
the bacteria developing that immune response and enough, you know,
they reached that tipping point where enough people have it
to where everyone's immune. But they lost a lot of

(07:22):
people along the way. Yeah, that's part of the problem
is is if you look at it on an individual level,
if you are exposed to a virus or a bacterium
and it runs rampant and infects you when you come
down with an illness from it, you there's basically two outcomes.
You can put it up, put up an immune response
and win, or you can lose and die. But if

(07:44):
you survive and win, you've become immunized. And that's just
the natural course of viruses or bacteria when they encounter humans.
It's at least contagious ones infectious ones, right, um. And
and we didn't have any recourse other than that. So
it's actually kind of good that we do have this
natural immune response to I mean, we just wouldn't be

(08:06):
around anymore if we didn't have. Its. Part and parcel
with human survival or any biological survival is to be
able to mount in immune response, build antibodies so that
if you do encounter this thing again. You don't have
to go through the illness all over again for the
most part. But like, we didn't have any other tools
besides that until the nineteen forties when we were able

(08:28):
to mass manufacture vaccines, and now all of a sudden,
we could say, create herd immunity without anybody ever having
to get sick or almost anybody, um, just through vaccination
vaccination programs. Yeah, and here's the deal to uh. In
you know, pre vaccination, they could build up an immunity,

(08:50):
lose a lot of people on the way, and it
wasn't like, all right, now we're fully set forever. Uh.
Sometimes there would be like another swell of exposure, whether
or not it's like a bunch of people moving into
the country or a bunch of people being born, but
basically non immune people kind of flooding the system. And
then that percentage point that we're going to talk about

(09:11):
dips below that number, and then you kind of you
don't have to restart the whole process, but it kind
of that hamster wheel gets going again until that herd
immunity is then reached again. Yeah. That's I think that's
um what's called an endemic disease where it's still they're
just hanging in the background. But for the most part,
people are immune to it. And then when you have

(09:31):
like an influx of births or an influx of immigrants,
that can flare up again. But then those people get
um kind of taken into the immunized herd, become part
of the immunized herd as well. And and the deal
is is that natural herd immunity is all we had
until we developed kind of the ability to make massive
quantities of vaccines, right I think of the starting in

(09:51):
the nineteen forties. Yeah, I mean there were a few
researchers along the way who really brought this along. There
was a couple of people, name a couple of dudes
named W. W. C. Topley and G. S. Wilson who
actually coined the term um herd immunity. But in ninety three.
That was an UH epidemiologist named A. W. Hydrick who

(10:15):
studied measles between ninety one and he's the one that
actually kind of quantified this and said, I've done the math.
If sixty percent of kids fifteen or younger were immune
to measles, then we're not going to have a big outbreak,
and he wrote a very famous paper about it, and
that's where the term really took off. Yeah, and so, um,

(10:35):
herd immunity is basically an epidemiological concept. It gets um sometimes,
I think in the in the popular press especially, it
gets kind of leaned on as if it's like a
natural universal law or something like that. It's basically an observation,
but one that has seems to be consistently held up

(10:56):
by the success of vaccination programs that we've cre aided
to generate artificial herd immunity. And that's the point. That's
the point of vaccine programs is to say, okay, for
for basically all of human history, all we had was
that natural herd immunity, whether we liked it or not.
But now that we have vaccines, we can create vaccine

(11:18):
programs where if we vaccinate enough people, we can force
this herd immunity without almost anybody getting sick. Like you
might have a slight reaction to the vaccine for a
small number of people, usually somewhere around like say three
to ten percent, the vaccine is not going to protect you.
But if enough people out there get this vaccine, they're

(11:40):
going to be vaccinated. Immunized against the disease without ever
having gotten it. And if enough people are vaccinated, we
will have this herd immunity without having to undergo some
disastrous epidemic that kills off some ungodly number of people
and makes an even larger number of people sick. That's
the basis of vaccines in the vaccination program. And I

(12:04):
mean countless tens of millions of lives have been saved
just from the fact that they have existed since the
nineteen forties. Yeah, I mean that's when they came into
mass production in se is, when we first started as humans.
To kind of understand this concept, there was a man
named Edward Jenner who inoculated a little kid, a little boy,

(12:25):
against smallpox. And this is kind of gross sounding, but
he infected him with the plus from a blister of
cow cow pox, which is less deadly, and he was like, Hey,
I think I'm onto something here, and in uh, two
hundred and or I guess a hundred and forty something years,
we're really going to be on the ball with this stuff, right.

(12:46):
And there were others like vaccines along the way, but um,
and I think they were all just kind of small batch.
You know, like artisan vaccines that were created, um, but
the uh, the it was like the forties where this
on this mass industrial scale that that they were produced.
And only under those circumstances can you actually get to

(13:08):
herd immunity for like a large population like a state
or a nation or a world. Basically, Yeah, and you know,
I think we've said this will kind of keep beating
this drum and repeating this, but the whole concept is
to protect people who haven't even been vaccinated. Just sometimes
you're too young to get vaccinated, Sometimes you have a

(13:29):
condition as a child where you literally can't be vaccinated,
or maybe you're elderly and you had been vaccinated. But
you know, they always talk about, especially with COVID nineteen
and and the flu, the elderly population is at risk
because they're way more likely to develop complications like uh,
pneumonia as a big one for what's going around now,

(13:51):
but as far as even something like chicken pox, encephalitis
or hepatitis. And we don't really know the deal with
children and adults their immune system and exactly how they
work and what the differences are, but it looks like
kids are either more robust and against something like chicken pox,
like when you have it as a kid is usually

(14:12):
not such a big deal. When you have it as
an adult, it is a big deal because it may
be your adult system just going into overdrive saying you
should have had this when you were six, Right, what
is wrong with you? Didn't you have any friends? Did
you have chicken pox? Probably didn't you? I did? I
did here. Yeah, my sister always had. She had a
pox scar like on her temple that I always admired,

(14:33):
so I made sure to like pick one on my temple.
I don't think Emily got it for some reason. I'm
that is in my brain. Oh my is she? Does
she have the vaccine against it? I think so? Okay,
because since the mid nineties they came out with a
vaccine against ari selah, which is the virus that causes
chicken pox, And now it's like you don't have to

(14:53):
get it as a kid any anymore. I'm pretty sure
somebody I know didn't get it and did get the vaccine,
and I'm pretty sure it's right, so pretty well so
um so with chicken pox, that's a good example of
how like you know, if you haven't when you're a kid,
it's I mean, it's still life threatening. You can get
all those same things like encephalitis or pneumonia, but you're

(15:16):
just way likelier to get it as an adult. Same
thing with the flu, Like the flu can be very
deadly depending on how old you are. UM, I think
something like it says ninety percent of flu related deaths
and fifty to seventy percent of hospitalizations for the flu
are for people over age sixty five. I mean, so

(15:38):
for the same exact strain of a bug that, like
you know, has a kid at home watching prices right
for one day, maybe two, UM, it lands an older
person over age sixty five in the hospital on the
brink of death. You know, it's just different. And so
because that there is that difference, it makes sense to
immunize the young, inoculate the young, to protect the elderly.

(16:02):
And let's not forget, even if you couldn't care less
about the elderly, you hate the elderly because some old
man yelled at you once when you threw a football
in his yard, and you've hated all old people ever since.
Then do you hate babies because there are there are
babies who are too young to be inoculated? And then
there's also those people, like you said, who don't have

(16:23):
um healthy enough immune systems to get a vaccine, and
so they rely on the everybody else the herd to
be vaccinated to provide this immunity for them. So there
are really good reasons to be vaccinated in addition to
you yourself being immunized against these things. Yeah, and you know,

(16:45):
these things work better in a homogeneous population. And every
time I see that word, I want to say homogeneous
for some reason, that's the British way of saying. Do
they say that way? They probably do, probably just to
be contrarian or contrary Indian. Uh, they work better and
homogeneous populations, which there are not a lot of those

(17:06):
uh still these days, um, thanks to you know, people
integrating with one another. So when they do these calculations
that we're about to talk about, they take all of
that into account, races, ethnicities, mixed races, stuff like that.
And so you know, we've been talking about the modeling
and the math involved. It can get complicated, but it's

(17:27):
really kind of simple that it's base form, don't you think, yes,
especially if you're a mathematical genius in a statistical whiz,
which I am not okay, But in the broad strokes, yeah,
you you can make a pretty good case that it's
understandable for sure that it's it's all based on the
reproduction number in relation to the size of the population. Basically, yeah,

(17:49):
and that reproduction number they in the in the biz,
it's pronounced are not. It's are with a. I guess
that's a zero. Huh, yeah, I'd to say our zero
any day. Are not though, for an infection, is a
number of people expected to contract that illness after coming
into contact with an infected person under the right conditions

(18:13):
that they can contract it. So a less confusing way
of saying that is the are not number is the
expected number of people that a contagious person is going
to infect. Right, So if you understand this about a disease,
if you know um, for example, with the MOMPS that's
extremely contagious, which means that it has a high are

(18:33):
not because the average person walking around infected with the
MOMPS and contagious with the MOMPS is going to get
something between ten and twelve other people infected with the
MOMPS and then they themselves will be contagious. So that
means that the MOMPS has a relatively high are not
or reproduction number. So if you understand that about the moms,
you can calculate how many people in a population have

(18:57):
to be immunized against the momps to to prevent it
from transmitting within that population. And, like we said, there's
a lot more math to it than that, but ultimately,
for the months in today's modern heterogeneous populations, is that
the right way of saying. I don't know. Nobody says heterogeneous,
do they. That sounds way too close to erotic. It

(19:21):
sounds like something I would say, so um uh, in
today's modern society, We'll just put it like that, you
need to have about of any given population immunized against
momps to reach what's called the herd immunity threshold. That
herd immunity threshold is basically what I just said. It's

(19:42):
the percentage of the population that has to be immunized
for her immunity to kick in to cover everybody else. Yeah,
and I know that everyone's going, what about COVID, What
about COVID? What about COVID? Oh? Do you want to
not even say yet? You want to wait? Okay, I
mean that's fine, that's fine. We'll how about this let's
take a break. Oh my god, this is just and

(20:03):
then right after the break, we'll we'll dive into this
stuff later, but right after the break, we'll give you
sort of what they're thinking as of today when we
record right after this shosh and shock. All right, So

(20:41):
that was an unfair cliffhanger, uh, And keep in mind,
like we kind of learned and we knew this was
going to happen with our COVID nineteen podcast, it was
out of date like days later, and this will be
out of date because there's just so much we don't
know yet and we're learning so much every day and
every week. But I've seen the range from six is

(21:02):
what they think the immunity threshold needs to be for
UH to have a pretty successful herd immunity, Right, that's
the current thinking that I saw as well, that they
think the reproduction number is somewhere between two and three.
I think that's a two point eight is like the
most widely touted for COVID nineteen, thankfully. I mean, can

(21:23):
you imagine if it was like a month's level, right, Yeah, No,
that's especially with the fact that there's such a thing
as asymptomatic carriers who can walk around in fating people.
If that was that much more contagious, it would be, Yeah,
it would be pretty rotten. Like it as bad as
it is, it could conceivably be worse epidemiologically speaking. Yeah,
And here's where we should also point out that, just

(21:45):
like we're talking about her immunity, but if we reach
her immunity, that doesn't mean like everything is solved. Um,
if we come up with a vaccine, which we will,
vaccines aren't effective against every single human, so things can
still happen. Um, And then sometimes you get an immunization
that's effective for a short time, for a few years. Maybe. Yeah,

(22:08):
there's an outbreak of diphtheria in Russia. I mean, like
tens of thousands of people fell ill with diphtheria, and
they were almost all adults. And they went back and
figured out the reason why this happened was because, um,
those adults hadn't been given a booster shot for their
diphtheria um inoculation and so so they're they're immune response.

(22:30):
They're antibodies that they built up when they were children
having been given this diphtheria vaccine had waned, and they
it waned enough that diphtheria was able to kind of
take over and and cause this outbreak. And so when
you look at it like that, that's almost a really
good analogy to herd immunity. It's like over time, the

(22:52):
the the that threshold can be can be can decline
so that the virus or the bacteria can get in
the same thing. The individual level, if you don't get
a booster shot if you need it. For some vaccines,
you don't need it. I think measles, moms, and rubella
are all considered UM to confer lifetime immunity if it
does work on you, and I think those are nine

(23:14):
seven percent effective. So for nine seven out of a
hundred people, when you get an mm ARE vaccine as
a kid, you don't need any kind of booster and
you're gonna be immune to it for life, right, which
is great. It is UM. That's the point of accedence. Yeah,
and this is where we need to dip our toe
into something UM. That's called vaccine hesitancy. That's that's what

(23:36):
the official name for it is UH. And this is
a situation we have UM. I'm not sure about other
countries because I didn't do a lot of research into that.
But here in the United States, especially certain parts of
the United States, there are vaccinine vaccine exemptions in place,
granted for philosophical purposes, religious purposes, personal reasons. UM. It

(24:00):
is important to point out here that personal reasons get
all the press. UM, like when you see articles about
anti vaxxer's as people that choose not to get their
child vaccinated for certain reasons. But the the largest percentage
of people who don't get vaccinated very sadly. UM. It
has to do with UH finances and poverty, right. I mean,

(24:23):
like it's it's if you want to vaccinate your kid,
but you can't because you don't have the money or
they're not available to you. I think kids in rural
areas have much lower vaccine rates than kids in urban areas. UM.
That is really sad, and I think that's something that
because it's such a public health success, UM, it should

(24:44):
be something that's much more widely available than anybody who
wants it. Yeah, here's some numbers on that. There was
a study by the CDC in that noted the percentage
of children without any vaccines had risen to about one
point three percent. And these are kids that were born
in the year two thousand fifteen, and then they compared

(25:06):
that with the two thousand one survey. They found it
was just point three percent of children between the ages
of nineteen to thirty five months. So basically they looked
at the numbers and they found that the children who
are uninsured or who live in rural areas like you said,
or maybe had Medicaid insurance. Seventeen point two percent of
the unvaccinated kids were uninsured compared to two point eight

(25:29):
percent of overall kids. There's a big deaf It is
a huge diff for sure, UM. And then there are,
like you said, there's parents who forego vaccinations, uh, for
personal reasons or religious reasons, UM, or philosophical reasons, although
I don't understand what the differences between philosophical and personal. Yeah,
I agree, UM, and I'd be interested to find that out.

(25:50):
But the people who don't vaccinate their kids for whatever reason,
who make a conscious decision not to are UM tend
to be viewed as freeloaders. And that's not just us
like throw in shade, that's like the term that that
is used as freeloaders. They're freeloading on the larger herd.

(26:10):
To UM, prevent from being exposed to this disease or
these diseases or viruses or bacteria, UM, because they're depending
on other people to immunize their kids through vaccinations instead.
That's right. Uh. And there's another weird phenomenon that's happened

(26:31):
here in the US that where a vaccine program is
so successful that generations will go by without any of
this disease. So you're not even familiar with it. So
it's sort of absurd in this way that it's been flipped.
But one of the reasons sometimes you will hear uh

(26:51):
to to not vaccinate. It's like, well, that old disease
that haven't you know that, we haven't seen that in
two hundred years, And I'm gonna put that vaccine in
Mike Kid and a cycle. Yeah, because the vaccine worked, right,
It's a victim of its own success. The vast vaccination
program is. And I think from what I can tell,
that's how UM public health officials typically explain uh anti

(27:14):
vaccine or declines in vaccine rates among people who consciously
choose not to that basically, they just haven't seen how
bad a disease is, Like you haven't seen what polio
can do. To somebody because you were born into a
world war. For all intents and purposes, polio just didn't exist, right,
And so you lose that incentive that somebody who is

(27:38):
aware of what polio can do, um the incentive that
that person has to vaccinate their kid. And then when
you couple that with um questions about a vaccine or
fears that there are some um negative side effects from
a vaccine, that disincentive or that lack of incentive becomes
a disincentive to get that. And so there's this ironic

(28:00):
circle that develops where those vaccination rates go down, we
dip below the herd immunity level, there's an outbreak of
that disease, and then the very people who lead to
that decline in vaccination levels point to that outbreak as
evidence that vaccines don't work or herd immunity doesn't work,

(28:21):
and it's it's um. It's hard to wrap your head around.
It is very hard to wrap your head around, especially
if you are fully on board the vaccine and UM
herd immunity through vaccine trains. It can be fairly galling,
I believe. Yeah. And there's a couple of things, A
couple of big challenges to herd immunity and whether or
not it can work today. And one of them is

(28:42):
that we can get on an airplane with our family
and we can fly great, great distances and get places
really fast and then come home again really fast. And
this happened in two thousand eight with the outbreak in
San Diego. That was a family that went to Switzerland
in um the this little boy picked up the virus

(29:04):
of the measles while he was in Switzerland. Such a
bad little boy he was. He was he he was unvaccinated,
He got sick. When he got home, he infected eleven
other people, including one who was an infant that was
too young to be vaccinated. Just if you were like
ambivalent about this through that that little detailing. Yeah, And

(29:28):
at first they were like, what is going on here
with this weird outbreak because we have a minimum threshold
here in San Diego against the measles for her community,
and in two thousand it was declared eliminated basically all
over the country. And so they started to kind of
poke around this case and they said, all right, San
Diego is doing great, but this kid actually goes to

(29:50):
a school and his localized social group is about seventeen
of them uh at this school don't vaccinate. So while
the city was doing fine, his little localized community had
a pretty high percentage of unvaccinated kids, and so that
allowed it to spread, right, It allowed it to spread.

(30:11):
Those kids became immunized, they became ill, but then they
became immunized to the measles naturally from being exposed to
it and having fallen ill um. But the big problem is,
in addition to the fact that it just kind of
ravaged this hyperlocal social group, there are other pockets within
the herd that probably bear a striking resemblance to that

(30:34):
social group. And those social groups come in contact with
the other social group that's been infected, you can have
an epidemic within the larger immunized herd, which you don't want.
You want those people to be protected. But the decline
in vaccine rates and the fact that we can travel,
like you were saying so easily, not only does it
mean that like a virus or bacteria can travel just

(30:56):
as fast on on board a human who's on a plane, um,
it also means that there's constant fluctuations to the percentage
that herd immunity threshold because of the influx and outflux
of people who are vaccinated or not vaccinated. Right, And
this is why those vaccination vaccination rates being high is

(31:18):
really important, um, because it's it's protecting everybody. Yes, you
want a large public buy in to the concept of vaccinations,
and when there is not a large public buying, then
your herd immunity is under threat and everybody who is
bought in is is um at risk. Because again you

(31:38):
might say, well, who cares if you if you've inoculated
your kids, if they're immunized against measles, what do you
care if somebody else's kid isn't because they have personal
reasons against it. Um, your kids find they're inoculated, don't
forget that. With the measles vaccine, I think it's like
pcent effective and that that means that if there's a

(32:00):
hundred hundred kids in a room and one of them
has full on contagious measles, which again is very contagious
like the mumps in its contagiousness, three of those kids
who have been vaccinated are possibly going to get the
measles from that kid even though they were vaccinated, because
their body just didn't form the right immune response or

(32:21):
enough of an immune response that they be protected if
they were exposed to that kid. So it is a
problem for even people who have been vaccinated against diseases
to have a decline and herd immunity. And then also,
don't forget the people who don't have uh an immune
system that can allow for them to be inoculated or vaccinated,

(32:41):
and the elderly who are just by virtue of being older,
more susceptible to a really hard about with whatever disease
it is they're being exposed to. Yeah, I've been running
up against that, that frustrating sort of circular um non
logic about COVID Night Team. I'm a member of a
Facebook page of a an area and more rural Georgia.

(33:06):
That's all I'll say. You could have just stopped at
a Facebook page. And there's been a lot of that
same sort of um circular logic of well, all these
models are turning out to be wrong. They weigh overstated
everything because look at the numbers falling. It's like that's
because we social distance and because we did all this

(33:27):
stuff and like it worked, that's how modeling works. Like
the initial numbers were really high because that was just
sort of the starting point, that was the input data
was here we are at the beginning, and this can
happen this way, and Americans got together by and large
at first at least and did the right thing, and
so those numbers went way down and it worked. And

(33:49):
then they're using that as proof of like we'll see
the modelings just off. They're just guessing. Yeah that a
mile away of course. Just yeah, yeah, everything is political,
huh yeah, And I'm just you know, I've tried to
I've tried to avoid it, but I have also commented
at times like modeling is not guessing. It is there.

(34:11):
There's real research and math that goes into it, and
and that math changes based on the input data. Like
in a month, there will probably be different numbers. And
it's not because they're just guessing and they're wrong, right right, Yeah,
it's um it's that distrust and expertise that has really
kind of wrecked things quite a bit. Yeah, all right,

(34:34):
let's talk about what's going on right now and how
this applies to our situation today with the novel coronavirus
COVID nineteen call it whatever you want, Well, wait a minute,
I think we should institute a tradition in this episode
where every time we're about to talk about COVID, we
make it a cliffhanger and take a break. Okay, all right,
we'll take a break and we'll talk about all that

(34:56):
right after this a shosh and shock. Alright, Chuck, thanks

(35:24):
for playing along with me. We're gonna have like fifty
ad breaks in here because we're gonna stop every time
right before we talk about COVID. Yeah. So, what we're
dealing with now in the most recent days, in a
couple of weeks, is a new sort of divide has emerged. Um.
Everyone got together at first, it seemed like and there

(35:46):
was a lot of unity for five minutes, and then
a dividing line has now formed. Um in the United
States and kind of in the world, depending on what
your view is on how to best handle this, and
the two sort of route are and we'll talk about
specific example examples of different countries and what they're doing.
But there's elimination and then there's herd immunity and vaccinations

(36:12):
and not by not pooping, you don't mean pooping. By elimination,
I mean getting rid of it, of the of the virus.
But not by pooping, no, not by pooping. But we're
talking about a few countries in particular. Everyone's talking about
Sweden right now because Sweden, compared to the rest of
the Nordic countries, the rest of Europe and most of

(36:32):
the rest of the world, was one country that was like,
you know what we are gonna say, if you feel sick,
stay at home. If you're at risk, maybe stay at home,
try and uh keep a safe distance from people. But
bars are open, restaurants are open. Um, no big concerts
or anything like that, and let's try and get that

(36:53):
herd immunity going instead of shutting everything down. Right. So
they're they're pursuing mixture of like social distancing guidelines, but
nothing that's being super enforced aside from you know, those gatherings,
like you said. But ultimately they're pursuing basically a strategy

(37:13):
of herd immunity while trying their best to keep the
curve flattened, right, And I think we're pushing this one
out sooner, So this will just be out like four
or five days from now, and all these numbers are
going to be changing. But the jury is kind of
still out on whether or not that's working in Sweden. UM,
as of a couple of days ago, they have a

(37:35):
far higher infection rate than their Nordic neighbors. UM not,
I mean it's a little lower than some other countries
to the south. So we just don't really know yet
because the jury is still out. We don't know what
our our percentage needs to be right now. Like I said,
it could be as high as eight percent, So we
just don't know. As these numbers come in over the

(37:57):
next month or two, it's gonna be really telling. UM.
I think kind of either way you slice it, it's
not right to say, all right, we'll look at Sweden
and if if it works there, that means it's gonna
work everywhere, because that's just not the case. No be
in Sweden has like consistently beat this drum. They're like, look,
we're not even sure this is gonna work for us,
but we're willing to try it. But we're far likelier

(38:20):
to be successful at something like this because our UM
population maybe is a little more collectivists than some other populations.
They're healthier, They are healthier, they have a big deal
a much stronger um and more responsive health care system.
They have a more homogeneous population don't forget, which may
mean that they could reach HERD immunity more quickly than

(38:42):
some other countries that have less homogeneous populations. Sweden is
more homogeneous. They also get this. They also they don't
have like huge mega grocery stores where there's a thousand
or undred people milling around all at the same time.
They have like smaller shops and markets serve like a
particular like corner in the neighborhood, and they have them

(39:04):
like every few corners, so there's not tons of people
in the market at every given at any given moment.
There's just a lot of differences between Swedish culture and
say American culture. That's that is giving the Swedes the
confidence to try this. But even still, there are people
in Sweden that are like, this is indefensibly reckless. We

(39:26):
can't do this, we can't try this is a stupid
and like you said, there are some early signs that
it is not going so well because compared to um Norway, Denmark,
and Finland, their death rate adjusted for um UH population
size is between three and six times the death rate
of those nations, and those nations tried elimination. Yeah, and

(39:50):
I saw that the UM. I don't. I don't think
it was like the I think it might have been
the head of whatever their CDC is said that they
were surprised by the death toll. Yeah, yeah, and not
in a way like they seem like really good people,
so it's not like, oh, we never thought of this,
but I think they were surprised. It is as high

(40:11):
as it's been right UM. And so Sweden is not
the only one trying this. India is trying it as well,
and they're doing something very similar to Sweden. They have
a lot of social distancing guidelines, but are also kind
of hoping for natural herd immunity to kick in UM.
And they don't have much of a choice there. They

(40:33):
have like point five five hospital beds, so a little
over half of a hospital bed per one thousand people
in the country, and forty four thousand ventilators UM. But
that both Sweden and India are taking a strategy of saying,
if you're older, if you're elderly, if you are in

(40:53):
this high risk group for suffering complications from COVID nineteen,
you stay home too, and we'll let the younger population
go out and get sick because they can handle it
better and maybe less of a strain on the health
care system. Um, and they'll be the immunized herd for
the rest of the population. I don't know if those
strategies are going to work or not, um, but that's

(41:15):
kind of like the mentality behind them. Yeah. And there
are other countries. I think in England they originally we're
going to kind of follow that model, and then everyone
said no way, bollocks to that, and so they have,
um got some stricter measures going. Belarus is the one
place that's really that. The president there, who's been in

(41:38):
office i think since, has called the stricter responses around
the world mass psychosis, and he's basically like, I mean
they're having a full on military parade this weekend and saying,
screw all this. Uh. And Belarus has one of Europe's
highest per capita infection rates. Yeah, it's like, have any
of you even seen there ownavirus and yourself I haven't. Yeah, jeez.

(42:05):
There was a guy on one of this that same
Facebook page that said I don't even know a single
person who's had it l O L. And I was like, well,
you're you're lucky, sir. You should be thankful for that,
and he's like, hmm, it's not luck could be something
else dot dot dot, and it's just like, I'm stepping
out of this immediately. Man, I don't know if I

(42:27):
I say hats off to you for being on that
Facebook group or just deeply pity you for being on
that Facebook group. Well I sort of have to be
because I have to keep up with some things. Uh.
This is a another part of Georgia where on a
little little tract of land. Oh gotch, So you need
to like nobody's squatting on it. Yeah, I'm the only squatter. So.

(42:49):
Um So, this whole herd immunity thing, there's herd immunity
itself has been controversial, uh since before the COVID nineteen pandemic. Right,
those same but who questioned vaccines also questioned the concept
of reaching herd immunity through vaccinations. There's like suspicion that, um,

(43:09):
you're artificially suppressing the vaccine and you're actually weakening the
immune system, and that it's going to set us up
for this horrible problem down the road. None of that
bears scrutiny under logic. Um, but today herd immunity has
kind of reached this controversial inflection point for a totally
different reason, and that the people who are saying, well,

(43:31):
we're going to opt for to try for her immunity
now rather than later so that we can get our
economy going again, what they're talking about is her community
without a vaccine. Big, big, big difference, huge difference, because
what they're talking about is basically reverting back to the
pre vaccine thing where it was just like, Okay, I

(43:52):
hope we get to herd immunity sooner than later, and
a lot of people are going to die along the way.
And that's one of the big flaws of this argument
of going for her immunity right now, which is there's
going to be a lot of people who die as
a result before we get to her immunity because we
don't have a vaccine there. We're going to have to

(44:12):
reach her community through just exposure to this virus, just
like in the old timey days. Yeah, I was about
to say, it's as if we were living in ancient
times and just sort of crossing our fingers. So lots
of death is a big flaw against it. Um If
if the reproduction number for stars Cove two is three,

(44:37):
that's confusing. But if it has, If if COVID nineteen
has a reproduction number of three, let's say um, and
that that means that the herd immunity threshold is about
se That's about the high end that anybody's saying is
seventy should stop the virus from spreading anymore. Right, So
if that's the case, then that means seventy of a

(44:58):
population would be sick. And I think a half to
one percent of a fatality rate would mean that of
the larger population, point three five to point seven percent
of the population will die. So if you know that,
and you can take just the populations of some of
these countries that are trying this and say, well, before

(45:20):
you reach her community, um Sweden, out of your population
of ten point to five million people, about thirty six
thousand to seventy two thousand are going to die along
the way. Statistically speaking, that's the number that you can
bet on, Yeah, between one point to five and about
two and a half a million in the US. And

(45:41):
if you're going to look at the world population, we're
talking numbers higher than the Spanish flu twenty seven to
about fifty four million people dead. And that's if you know,
we're not saying like that's gonna happen. We're saying that's
if the whole world took the approach of just all right,
let's just see how we do, you know, right, And
and I mean like this, that's we're a virgin population humanity,

(46:07):
not just the US, not just Canada, not just the UK,
not just Sweden. The world is a virgin population to
this virus because it's a novel coronavirus. We've never no
one on Earth has ever been exposed to this particular
virus before, so there isn't any pre built in immunity
like there would be if it makes another round a
year from now, right, So it just burns. Viruses and

(46:31):
bacteria burn their way through populations like that. So you
can imagine it would spread, uh, pretty effectively. And if
the fatality rate really is a half to one percent,
those numbers could be pretty real depending on what what
measures we take to mitigate those, Like you were saying,
so death that's a big, big problem, um. And also
along the way, we would be doing the opposite of

(46:55):
flattening the curve by just letting people go out and
getting sick to get things over with. Yeah. I mean,
we we've worked so hard to flatten the curve and
it worked in most of the most of the United States,
except you know, these weird outbreaks in in smaller towns
that didn't have enough beds and then laters and that's
all been really really sad to see happen. But by

(47:16):
and large, we did the right thing for a while
and it flattened the curve pretty well. But this would
fatten that curve right back up. Uh, and we'd be
in that same like in a worse situation than we
were going in, right. So, um, that's another big one.
And then also took reinfection is another huge flaw in this.
We don't know if stars cove two, which causes COVID nineteen, um,

(47:42):
how fast it's mutating. If it's like other coronaviruses or
other flu viruses, it probably has a lot of what's
called antigenic drift, where it mutates really rapidly and creates
new strains that the antibodies that have built up this
immune defense against one variety are useless to fight this

(48:03):
new variety. Right. Yeah, some diseases don't do that, like polio.
The reason our polio vaccine has been so successful is
because it doesn't mutate very much, it doesn't call it,
it doesn't create new strains. With coronavirus is they tend
to do that a lot, so there's a real chance
for reinfection. So this herd immunity will just be like
this ongoing thing until we can come up with the

(48:25):
viable vaccine that can that can protect us from basically
any mutated variety of this coronavirus. That's right, an antigenic drift.
Do I need to say it? No? You don't, great? Great?
Oh yeah, Chuck, I think he's for sure that that

(48:48):
muted trumpet thing that they got going on. What's that
thing called on the trumpet that they make that sound with.
Oh yeah, the plunger plunger head muffler, the thing. I
don't know. Yeah, you're on the trolley. So. Uh. The
other thing that we need to consider, and that is

(49:08):
the other sort of way that you can go about
this is elimination. Elimination that we were talking about, and
not pooping, and that is the opposite tactic, and that's
what most of the world has done, including the u S,
which is self quarantining, isolating, trying to contain the virus,
closing borders, mass gloves, all that stuff. Um, we have

(49:31):
flattened the curve for the most part. Other countries have
come close to elimination. New Zealand is getting a lot
of press because they and you know, they got a
lot of Again, you can't say, like, well, the same
thing could happen here in the US because New Zealand
is a very isolated place and it's a smaller population
and they have super smart elected officials and smart people

(49:52):
who listen to those elected officials. Good to get no, man,
someone come at me news. England's Prime minister is amazing.
She's she's like one of the best. Yeah. I remember
when we were there. Um, we got a cabra, do
you me? And I did to the airport and this
this guy, I think it was an immigrant from Sri
Lanka and he just could not stop boasting about how

(50:14):
great the New Zealand government was, about how taking care
of their population was, how like how much of a
sense of community the whole country had, and it was
just really refreshing to experience. Yeah it is, Uh, maybe
we should move there anyway. So the thing about New Zealand, Yeah,
I'm sure there's some people listening like yeah, why don't

(50:34):
you move there if you love it so much? And
there's there's also Kiwis that are going come on over,
We'd love to have you. And then there's also probably
some there like please don't. We've had enough of you too.
So why it worked there though, was because, like I said,
they have you have to have everyone on board, and
it seemed like most everyone on board or got on

(50:56):
board in New Zealand, and that's just not happened here.
So yeah, and I mean, it really has worked for
New Zealand, but they've taken serious restrictions, like you you
can't fly if you want to domestically, they shut down
their reports. If you want to fly to New Zealand,
t s for you, you're not gonna get anywhere near
the country. But in addition that, if you're a New

(51:17):
Zealand citizen, you can't fly from one place to another
if you want to just for the heck of it. Right,
There's so they've really insted instituted some draconian measures, but
it seems to have worked. Like there was a report
that came out two days ago on May fourth, that
says that the models originally used to project how many cases.
New Zealand was going to have said that they were

(51:39):
going to get something like a thousand cases a day
if they did nothing like no lockdown measures. All they've
had since March is fourteen hundred and eighty seven cases,
not a thousand a day, seven cases total, and they've
only had twenty deaths. So it seems like elimination can work.
And for that reason, and a lot of people are

(52:01):
a lot of countries have said this is what we're
gonna try, and elimination just amounts to hiding out from
the virus until a vaccine can be developed. The problem
is there are serious flaws to that too, depending on
what kind of what kind of government and culture that
you have. But even without that, depending on that, it
requires that everybody act basically perfectly and avoid everybody else

(52:28):
and give up your job, give up your economy and
wait until somebody comes up with a vaccine. And that
can be a really pricey, costly measure. Yeah, which is
why a lot of people are like this, this we
got to find some other way, Yeah, And they've looked
at um there are like ways you can look at
the countries and decide whether or not people are going

(52:49):
to comply or not. Um, there was uh some cultural data.
There was a company called half Steata Insights, and they
look it things like individualism of a population, basically like
whether or not people are gonna all go along or
if people are like heck no, man, I want my freedoms.

(53:10):
I'm an individual, I'm an American and you can't tell
me what to do, right. And you might not be
surprised to learn that in Sweden, Uh they have a
rank of seventy one out of one hundred as on individualism.
Uh the U scores ninety one out of a hundred,
so basically out of a hundred would be uh difficult

(53:32):
to maintain. You know, these kind of restrictions for too long.
I mean, if you look at it like that, it's remarkable,
how it's remarkable, in heartening, how much people have given
up individual liberties for the greater good in this pandemic
in the United States. Then, like I hadn't looked at
it that way. I just kind of saw like one

(53:53):
and thought, okay, you know that's that's that's a that's
a high score. There's a lot of individualism in the
United States. We gotta into visual streak like nobody's business, right,
But if you look at it almost like it's a
it's a percentage of the population that will listen in
situations like this, then it really does kind of go
to show you how how much of a sacrifice people

(54:13):
have made, not just Americans. I don't want to just
say it like that, Like if you're in a collective
of society, you're still sacrificing for the greater good. It's
just possibly a little more culturally ingrained in you that
this is the thing to do. But either way, the
idea of people people sacrificing for others is is it's heartening.

(54:33):
The problem is is people can only sacrifice for so
long until you have just massive economic drawbacks. And and
that's the thing. So if you follow the forced herd
immunity natural herd immunity strategy towards COVID nineteen, you will
it will result in a lot of deaths. If you

(54:55):
follow the elimination strategy, it results in a trem in
this amount of economic hardship. And it's easy to say,
chuck like, well, lives lost tops economic hardship any day
of the week, And ultimately, yes it does. But it's
you really should not um understate the toll in human

(55:19):
misery of economic hardships and how bad this has gotten
for some people and how quickly. Yeah, And the other
thing I'll say too, is one of the arguments I've
heard is that, you know, there are going to be
so many deaths from people who are who are depressed
because they can't go out, and people dying by suicide

(55:40):
and stuff like that, which you know, I don't want
to minimize that because that that for sure has an
impact on people. But I saw a tweet from a
guy that was talking about can we just stop pretending
that our former world of like working fifty hours a
week and commuting in a stressful environment and hectic crowds
and mask consu umerism and pollution and everything else was

(56:02):
like a mental health utopia. So it's you know, you've
got to kind of look at the big picture and
not just pick and choose what you're going to highlight
because it fits your narrative. You know. Yeah, I think
one of the like the few good outcomes so far
of this has been like a huge down shift in
that um manic productivity that drives most Americans, you know. Yeah,

(56:26):
And you know, here's The thing is, we don't know.
Everything is so new. We're not gonna sit here and
pretend like there is only one right way, like, we
don't know. So there's so much that we don't know
about this is we don't know the exact right path
forward yet as a population, and the medical community doesn't
know the exact right path forward. We're all trying to
figure this out in real time and build the road

(56:50):
as we're driving on it or whatever that expression is.
And you know, I have my money on uh, staying
at home, slowing this thing down and elimination. Other people
might feel a different way, But it seems like that
way is working better. Yeah it is. But again, if
you it's still early and the data is still coming in.

(57:12):
There was a report this week of a hundred New
York hospitals. They found that six or six percent of
new cases where among people who had stayed at home
and mostly followed the elimination strategy. So this one guy,
this doctor who wrote an article that I read, Dr
Stephen Phillips. He said, look, man, like, in addition to

(57:32):
all the stuff that we need to be doing to
handle this pandemic, let's also create like a really robust
data sharing um arrangement, so that we can look back
a year or a few years from now and study
this and say, oh, actually, these countries followed elimination mixed
with the social distancing guidelines, or they followed herd uh

(57:56):
immunity pursuit um and they actually came out on top.
So that we will know the next time which one
actually does work. Taking everything into account the cost in lives,
the economic cost, the cost and personal liberty, and find
the best way forward. And it probably won't be a
panacea where everything works like one thing works for every country,

(58:16):
but we'll have a pretty good model hopefully that can
be adjusted to suit the individual country that's adopting it. Hopefully.
That's if we can get past all of the arguing
over whether this is even real or not. Yeah, and
I know it's hard right now, but I think that
the most dangerous thing right now is to have the

(58:38):
mindset of, well, you know what, I'm pretty kg and
the weather is nice, and I don't know anyone personally
who's gotten it, so I'm just sort of going to
ease back into normality here. I think that's that's when
the second wave comes and things get worse and it's tough, uh,
and everyone is anti and KG myself include did you

(59:00):
know I find myself wanting to do things. Um, and
it's tough on on kids especially, But I think it's
more important now than ever to keep up what's what
we're doing. Yeah, we haven't just magically wished the pandemic away.
It didn't work. No, and lovely weather. Um, you know
to take your walks, get outside, do it safely, but

(59:21):
that it is not a reason to be like, well
that's old news. Now we can just go back to normal,
right right. I saw a post to button it up.
I'm sorry we keep going back back and forth on this,
but I saw a post that said, um, easing of
lockdown doesn't mean that the pandemic has gone away. It
means that they have a hospital bed for you now,

(59:42):
right exactly? You got anything else? I got nothing else? Man?
All right, Well that's it for her community. Hopefully you
guys learned something I definitely did from researching all this,
and we hope everyone out there is staying safe, insane
and uh, hanging in there. That's right. Uh. Since I
said hanging in there, it's time chuck for listener mail.

(01:00:05):
I'm gonna call this thanks from England and a little
shout out. Hey, guys, I wanted to say thank you,
thank you for your ongoing efforts with Stuff you Should Know.
It's been a welcome distraction at work. I, along with
so many feel like we know you guys so well
with Stuff you Should Know and Chuck's movie Crush and
Josh's Into the World podcasts. I hope your families remain

(01:00:25):
safe and from my son Dexter and I we wish
you all the best for yourselves in the future of
the podcast. Sorry to ramble on, which, by the way, Ben,
that was not rambling on. That was concise and beautiful.
But you're from England, so you're very kind. Uh. Sorry
to ramble On, but I was wondering if you would
be kind enough to shout out all the UK NHS
staff that are helping us over here. I have friends

(01:00:48):
and family that work for the NHS services and this
is the only way I know how to say thank you,
So for sure, Ben, thank you to not only them,
but to medical providers all over the world who are
working hard risking their own lives UM, often with UM
equipment that's being reused when it shouldn't be and uh,

(01:01:09):
I'm not going to wade into those waters. But you
don't have all that you need to do your job
right now and that's terrible and we should not be
in this position. But we are so thank you. Uh.
He also says ps Torquay. We heard from a bunch
of people on this uh you mentioned the other week
and I think that Agatha Christie segment we would pronounce

(01:01:30):
it tour as in tour bus and key Torquay. It's
always fun to hear how everyone pronounces these bloody silly
towns over here. Kind regards. That is from Ben Cleaver
and Harrowgates, England. Hirogaty Ben. That was such a good
email that we are now friends. That's right, thank you

(01:01:52):
for that. That was much needed man Um, thanks a
lot for that, and we will very happily shout out
the entire NHS, especially all of the people who are
out there on the front lines working to save people's
lives against COVID nineteen or anything that happens to it
befallen them. That's right, Um, Thanks again, Ben, And if
you want to be like Ben and get in touch

(01:02:13):
with us, whether you want to tell us to stop
being so political, or you want to tell us that
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