Stuff You Should Know - How Herd Immunity Works

Episode Date: May 12, 2020

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. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

On the podcast, Hey Dude, the 90s called, David Lasher and Christine Taylor, stars of the cult classic show, Hey Dude, bring you back to the days of slip dresses and choker necklaces. We're gonna use Hey Dude as our jumping off point, but we are going to unpack and dive back into the decade of the 90s.

We lived it, and now we're calling on all of our friends to come back and relive it. Listen to Hey Dude, the 90s called on the iHeart radio app, Apple Podcasts, or wherever you get your podcasts. Hey, I'm Lance Bass, host of the new iHeart podcast, Frosted Tips with Lance Bass. Do you ever think to yourself, what advice would Lance Bass

and my favorite boy bands give me in this situation? If you do, you've come to the right place because I'm here to help. And a different hot, sexy teen crush boy bander each week to guide you through life. Tell everybody, ya everybody, about my new podcast and make sure to listen so we'll never, ever have to say. Bye, bye, bye.

Listen to Frosted Tips with Lance Bass on the iHeart radio app, Apple Podcasts, or wherever you listen to podcasts. Welcome to Step You Should Know, a production of iHeart radios, How Stuff Works. Hey Ian, welcome to the podcast. I'm Josh Clark. There's Charles W. Chuck Bryan over there.

And it's just the two of us again, but I'm getting used to it. How about you? I am, I am sweating in our studio by myself. Like you're nervous? No, 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. Oh my. And I ate some of that spicy beef ramen in this hot room. Yeah, that's a dangerous combo. 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 on the Movie Crush page. Yeah, well, it's a pretty hilarious term, but just please put down like some newspaper or something on the chair before you sit on it bare bottomed, okay? Oh, and by the way, speaking of Movie Crush,

you, I think this is gonna come out the day after your Movie Crush, Mini Crush appearance next week. Yeah, I'm excited about it, man. 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. Or stick around, maybe boost the numbers it had. But it was a lot of fun. And I think people would want to hear your appearance as well. I really appreciated you having me on. It was a lot of fun. You're a consummate professional at hosting.

Hey, it turns out we know what we're doing here, don't we? Don't jinx us. Speaking of which, I think we should front load this episode with a little bit of a COA. If you are a pretty hard line anti-vaxxer or if you believe in things like the pandemic or that Bill Gates created the coronavirus for population control.

Sure. You may not wanna listen to this because we're gonna bring you hard and lean facts. Lean and mean, depending on your point of view. I think that's a good COA. I think that maybe you got rid of 2% of the hate mail we're gonna get. So thank you for that.

Yeah, we'll see. I mean, I think it just bears saying, just why rile yourself all up? Just listen to your echo chamber podcast that validate what you think. Maybe or, or, or, or ideally calm down and just hear us out and see what you think. Well, that's always an option, you know.

So we're not even talking necessarily just about vaccines or anti-vaxxings. It's almost like a side thing to this whole thing, but it's definitely still very much intertwined with it. We're talking about herd immunity. Or you can't not talk about vaccines if you're gonna talk about herd immunity. Right, no, because with herd immunity,

especially in the 21st century, there's basically two ways of getting there. And one of them is a robust vaccination program. That's right. And if you don't know what herd immunity is, 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 though is the principle sort of in its simplest form of safety in numbers. And if you have a lot of people or enough people, cause there's actual math involved to figuring that out, it's not just a guess. If you have enough people that are immune to a virus,

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 aren't immune. That's the idea that so many, a certain threshold of people are immune that even people that choose not to vaccinate

can hop on that wagon. Right. And it's not even like you hop on the wagon, like you are on the wagon just by virtue of being alive in the society or culture, right? That's a good point. There's a really easy way of understanding it that Molly Edmonds used

in the How Stuff Works episode on herd 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 their bubble that they live in, their work, their home and everything, and they don't encounter anybody else. Just that.

It's kind of like Wally, but with bowling. Right. If the first person on lane one comes down with, say, the flu, 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 antibodies. Some of those people will die, most will survive, and the flu will have a hard time getting through that population a second time around. But if the woman 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 gonna transmit beyond her. So she's protected everybody in lanes three through 10 just by virtue of having been immune to that flu virus. It stopped with her, and that's the point of herd immunity. 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, 10 splits, which she could if she wanted to, that's how immune she is. Yeah, the perfect game. I remember that dumb joke when I was little about, you know, you learn the stupidest jokes when you're a kid. Sure.

Because they have to be so dumb a kid can understand them, I think. I think so, maybe. But about the guy who bowled a 301, and you're like, you can't bowl a 301. Well, you can't bowl a 300 and lose. Man. I know, that's how bad it was,

and that's how much it stuck with me. Did you get that from Highlights? I don't know where I got that, it was pretty bad. Sounds like a playground joke. I think so, but I think you get beat up in the playground even with that one. Yeah, so let's talk about herd immunity some more. We talked about the two ways,

natural exposure and vaccinations. Yeah. And if we're going back pre-vaccination and talking about human history, the herd, there was herd immunity, and it was, I guess the way to describe it is herd immunity the hard way. 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 people along the way. Yeah, that's part of the problem 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

and you come down with an illness from it, there's basically two outcomes. You can put up an immune response and win, or you can lose and die, but if you survive and win, you've become immunized, and that's just the natural course of viruses or bacteria when they encounter humans, at least contagious ones, infectious ones, right?

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... Yeah, sure. I mean, we just wouldn't be around anymore if we didn't have it. It's part and parcel with human survival or any biological survival,

is to be able to mount an 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 1940s, when we were able 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, just through vaccination programs. Yeah, and here's the deal too. In pre-vaccination, they could build up an immunity, lose a lot of people on the way, and it wasn't like, all right, now we're fully set forever.

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 gonna talk about 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 what's called an endemic disease where it's still there just hanging in the background, but for the most part, people are immune to it. And then when you have like an influx of births or an influx of immigrants, it can flare up again. But then those people get kind of taken

into the immunized herd and become part of the immunized herd as well. 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 the 1940s. Yeah, I mean, there were a few researchers along the way who really brought this along.

There was a couple of people named, a couple of dudes named WWC Topley and GS Wilson, who actually coined the term herd immunity. But in 1933, there was an epidemiologist named A.W. Hydrick who studied measles between 1900 and 1931. And he's the one that actually kind of quantified this and said, I've done the math. If 68% of kids, 15 or younger, were immune to measles,

then we're not gonna 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 herd immunity is basically an epidemiological concept. It gets, sometimes I think 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 seems to be consistently held up by the success of vaccination programs that we've created to generate artificial herd immunity. And that's the point. That's the point of vaccine programs is to say, okay, 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 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 10%, the vaccine's not going to protect you. But if enough people out there get this vaccine, they're 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 mean, countless tens of millions of lives have been saved just from the fact that they have existed since the 1940s. Yeah, I mean, that's when they came into mass production.

In 1796 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 against smallpox. And this is kind of gross sounding, but he infected him with the pus from a blister of cowpox, which is less deadly.

And he was like, hey, I think I'm onto something here. And in 200 and, or I guess 140 something years, we're really gonna be on the ball with this stuff. Right, and there were other like vaccines along the way, but, and I think they were all just kind of small batch, you know, like artisan vaccines that were created. But the, it was like the forties where this on this mass industrial scale

that they were produced. And only under those circumstances can you actually get to 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, we'll kind of keep beating this drum and repeating this, but the whole concept is to protect people

who haven't even been vaccinated. Because sometimes you're too young to get vaccinated. Sometimes you have a condition as a child where you literally can't be vaccinated or maybe you're elderly and you had been vaccinated, but you know, what they always talk about, especially with COVID-19 and the flu, the elderly population is at risk

because they're way more likely to develop complications like pneumonia is a big one for what's going around now. But as far as even something like chickenpox, encephalitis or hepatitis, and we don't really know the deal with children and adults in their immune systems and exactly how they work and what the differences are, but it looks like kids are either more robust

and against something like chickenpox. Like when you have it as a kid, it's usually 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, you had chickenpox probably, didn't you? I did, I did. Same here. Yeah, my sister always had, she had a pox scar like on her temple that I always admired. So I made sure to like pick one on my temple. I don't think Emily got it for some reason,

that is in my brain. Oh my, does she have the vaccine against it? I think so. Okay, cause since the mid 90s, they came out with a vaccine against varicella, which is the virus that causes chickenpox. And now it's like, you don't have to get it as a kid anymore.

I'm pretty sure somebody I know didn't get it and did get the vaccine and I'm pretty sure it's my wife. Right. So you know her pretty well. So with chickenpox, that's a good example of how like, you know, if you have it 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 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. I think something like, it says 90% of flu-related deaths and 50 to 70% of hospitalizations for the flu are for people over age 65.

I mean, so 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, it lands an older person over age 65 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. 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 babies who are too young to be inoculated. And then there's also those people, like you said, who don't have 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, these things work better in a homogenous population. And every time I see that word, I want to say homogeneous for some reason. That's the British way of saying it. Do they say it that way? They probably do.

Probably just to be contrarian or contrarian. They work better in homogenous populations, which there are not a lot of those still these days thanks to 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 we've been talking about the modeling and the math involved. It can get complicated, but it's really kind of simple at its base form, don't you think? Yes, especially if you're a mathematical genius in a statistical way, which I am not. Oh, okay.

But in the broad strokes, yeah, you can make a pretty good case that it's understandable for sure. It's all based on the reproduction number in relation to the size of the population, basically. Yeah, and that reproduction number, they in the biz, it's pronounced are not. It's are with a, I guess that's a zero, huh?

Yeah, I'd rather say are zero any day of the week. Are zero, yeah. Are not though for an infection is a number of people expected to contract that illness after coming to contact with an infected person under the right conditions 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 gonna infect. Right, so if you understand this about a disease, if you know, for example, with the mumps, it's extremely contagious, which means that it has a high are not because the average person walking around infected with the mumps and contagious with the mumps is going to get something between 10 and 12 other people

infected with the mumps and then they themselves will be contagious. So that means that the mumps has a relatively high are not or reproduction number. So if you understand that about the mumps, you can calculate how many people in a population have to be immunized against the mumps 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 mumps in today's modern heterogeneous populations, is that the right way of saying it? I don't know. Nobody says heterogeneous, do they? That sounds way too close to erotic. It sounds like something I would say.

So in today's modern society, we'll just put it like that. Yes. You need to have about 95% of any given population immunized against mumps to reach what's called the herd immunity threshold. And that herd immunity threshold is basically what I just said, it's the percentage of the population that has to be immunized for herd 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? Just wait. You wanna not even say yet, you wanna wait? Okay, that's fine.

That's fine. Well, how about this? Let's take a break. Oh my God, this is just, I can't. And then right after the break, we'll dive into the 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. Singing stuff with Joshua and Charles, stuff you should know. On the podcast, Hey Dude, the 90s called, David Lasher and Christine Taylor, stars of the cult classic show, Hey Dude, bring you back to the days of slip dresses and choker necklaces.

We're gonna use Hey Dude as our jumping off point, but we are going to unpack and dive back into the decade of the 90s. We lived it, and now we're calling on all of our friends to come back and relive it. It's a podcast packed with interviews, co-stars, friends, and non-stop references to the best decade ever.

Do you remember going to Blockbuster? Do you remember Nintendo 64? Do you remember getting Frosted Tips? Was that a cereal? No, it was hair. Do you remember AOL Instant Messenger and the dial-up sound like poltergeist? So leave a code on your best friend's beeper,

because you'll wanna be there when the nostalgia starts flowing. Each episode will rival the feeling of taking out the cartridge from your Game Boy, blowing on it and popping it back in, as we take you back to the 90s. Listen to Hey Dude, the 90s, called on the iHeart Radio app,

Apple Podcasts, or wherever you get your podcasts. Hey, I'm Lance Bass, host of the new iHeart Podcast, Frosted Tips with Lance Bass. The hardest thing can be knowing who to turn to when questions arise or times get tough, or you're at the end of the road. Ah, okay, I see what you're doing. Do you ever think to yourself,

what advice would Lance Bass and my favorite boy bands give me in this situation? If you do, you've come to the right place, because I'm here to help. This, I promise you. Oh, God. Seriously, I swear. And you won't have to send an SOS,

because I'll be there for you. Oh, man. And so, my husband, Michael. Um, hey, that's me. Yep, we know that, Michael. And a different hot, sexy teen crush boy bander each week to guide you through life, step by step. Oh, not another one.

Kids, relationships, life in general can get messy. You may be thinking, this is the story of my life. Oh, just stop now. If so, tell everybody, yeah, everybody, about my new podcast and make sure to listen, so we'll never, ever have to say bye-bye-bye. Listen to Frosted Tips with Lance Bass on the iHeart Radio app, Apple Podcasts,

or wherever you listen to podcasts. All right, so that was an unfair cliffhanger. And keep in mind, like, we kind of learned, and we knew this was gonna happen with our COVID-19 podcast. It was out of date, like, days later. Sure. 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 60% to 80% is what they think the immunity threshold needs to be for 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 I saw 2.8 is, like, the most widely touted for COVID-19, for Corona. Thankfully, I mean, can you imagine if it was, like, a mom's level? Right, yeah, no, that's, especially with the fact that there's such a thing as asymptomatic carriers who can walk around infecting people. If it was that much more contagious, it would be,

yeah, it'd be pretty rotten. Like, as bad as it is, it could conceivably be worse epidemiologically speaking. Yeah, and here's where we should also point out that just, like, we're talking about herd immunity, but if we reach herd immunity, that doesn't mean, like, everything is solved. If we come up with a vaccine, which we will,

vaccines aren't 100% effective against every single human. So things can still happen. And then sometimes you get an immunization that's effective for a short time, for a few years maybe. Yeah, there's an outbreak of diphtheria in Russia in 1994. 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 those adults hadn't been given a booster shot for their diphtheria inoculation. And so their immune response, their antibodies that they'd built up when they were children haven't been given this diphtheria vaccine had waned. And it waned enough that diphtheria was able to kind of take over 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, that threshold can decline so that the virus or the bacteria can get in. Same thing on 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, mumps, and rubella are all considered

to confer lifetime immunity if it does work on you. And I think those are 97% effective. So for 97 out of 100 people, when you get an MMR 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 great, that's the point of vaccines.

Yeah, and this is where we need to dip our toe into something that's called vaccine hesitancy. That's what the official name for it is. And this is a situation we have. I'm not sure about other countries because I didn't do a lot of research into that, but here in the United States, and especially certain parts of the United States,

there are vaccine exemptions in place, granted for philosophical purposes, religious purposes, personal reasons. It is important to point out here that personal reasons get all the press. Like when you see articles about anti-vaxxers as people that choose not to get their child vaccinated for certain reasons,

but the largest percentage of people who don't get vaccinated, very sadly, it has to do with finances and poverty. Right, I mean, 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.

That is really sad. And I think that's something that because it's such a public health success, it should 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 2017 that noted the percentage of children

without any vaccines had risen to about 1.3%. And these are kids that were born in the year 2015. And then they compared that with the 2001 survey. They found it was just 0.3% of children between the ages of 19 to 35 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, 17.2% of the unvaccinated kids were uninsured compared to 2.8% of overall kids. Right. That's a big diff. It is a huge diff for sure. And then there are, like you said, there's parents who forego vaccinations

for personal reasons or religious reasons or philosophical reasons. Although I don't understand what the difference is between philosophical and personal. Yeah, I agree. And I'd be interested to find that out, but the people who don't vaccinate their kids for whatever reason, who make a conscious decision not to,

are tend to be viewed as freeloaders. And that's not just us like throw in shade. That's like the term that is used as freeloaders. They're freeloading on the larger herd to prevent from being exposed to this disease or these diseases or viruses or bacteria because they're depending on other people to immunize their kids through vaccinations instead.

That's right. And there's another weird phenomenon that's happened 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

to not vaccinate is like, well, that old disease, I haven't, you know, we haven't seen that in 200 years. And I'm gonna put that vaccine in my kid and it's like, well, yeah, because the vaccine worked. Right, it's a victim of its own success. The vaccination program is, and I think from what I can tell, that's how public health officials typically explain anti-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 where for all intents and purposes polio just didn't exist, right? And so you lose that incentive that somebody who is aware of what polio can do, the incentive that that person has to vaccinate their kid.

And then when you couple that with questions about a vaccine or fears that there are some 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 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 led to that decline in vaccination levels point to that outbreak as evidence that vaccines don't work or herd immunity doesn't work. And it's- It's hard to wrap your head around. It is very hard to wrap your head around it, especially if you are fully on board the vaccine

and 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 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 2008 with the outbreak in San Diego that was a family that went to Switzerland. This little boy picked up the virus of the measles while he was in Switzerland. Such a bad little boy. He was, no, he was so bad. He was so naughty.

He was unvaccinated. He got sick when he got home. He infected 11 other people, including one who was an infant that was too young to be vaccinated. Yeah, just if you were ambivalent about this. Right. They threw that little detail in.

Yeah, and at first they were like, what is going on here with this weird outbreak? Because we have 95%, a minimum threshold here in San Diego, 95% against the measles for herd immunity. And in 2000, 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's doing great,

but this kid actually goes to a school and his localized social group is about 17% of them at the 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.

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. But the big problem is in addition to the fact that it just kind of ravaged this hyper-local social group, there are other pockets within the herd that probably bear a striking resemblance to that social group.

And if 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 a bacteria can travel just as fast on board a human who's on a plane, 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 rates being high is really important

because 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 buy-in, then your herd immunity is under threat. And everybody who is bought in is at risk because again, you might say, well, who cares? 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? Your kid's fine, they're inoculated. Don't forget that with the measles vaccine, I think it's like 97% effective in that that means that if there's 100 kids in a room and one of them has full-on contagious measles,

which again is very contagious, it's 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 enough of an immune response that they'd 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 in herd immunity. And then also don't forget the people who don't have an immune system that can allow for them to be inoculated or vaccinated. And the elderly who are just by virtue of being older, more susceptible to a really hard bout

with whatever disease it is they're being exposed to. Yeah, I've been running up against that frustrating sort of circular, non-logic about COVID-19. I'm a member of a Facebook page of a- Oh boy. An area in more rural Georgia, 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 circular logic

of, well, all these models are turning out to be wrong. They way overstated everything because look at the numbers falling. It's like, that's because we social distance and because we did all this stuff. Right, it worked. 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 then they are using that as proof of like,

we'll see the modeling's just off. They're just guessing. Yeah, I saw that coming like a mile away. Oh, of course. Just, yeah, it's, yeah. Everything's political, huh? Yeah, and I'm just, I've tried to avoid it but I have also commented at times

like modeling is not guessing. It is, there's real research in math that goes into it and that math changes based on the input data. Like in a month, there will probably be different numbers and it's not cause they're just guessing and they're wrong. Right, right. Yeah, it's, I think it's that distrust and expertise that has really kind of wrecked things quite a bit.

Yeah, all right. Let's talk about what's going on right now and how this applies to our situation today with the 2020 novel coronavirus COVID-19, 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. Oh, okay. All right, we'll take a break and we'll talk about all that right after this. Learning stuff with Joshua and Charles. Stars, stuff you should know. On the podcast, Hey Dude, the 90s called David Lasher and Christine Taylor,

stars of the cult classic show, Hey Dude, bring you back to the days of slip dresses and choker necklaces. We're gonna use Hey Dude as our jumping off point but we are going to unpack and dive back into the decade of the 90s. We lived it and now we're calling on all of our friends to come back and relive it.

It's a podcast packed with interviews, co-stars, friends and non-stop references to the best decade ever. Do you remember going to Blockbuster? Do you remember Nintendo 64? Do you remember getting frosted tips? Was that a cereal? No, it was hair.

Do you remember AOL instant messenger and the dial-up sound like poltergeist? So leave a code on your best friend's beeper because you'll wanna be there when the nostalgia starts flowing. Each episode will rival the feeling of taking out the cartridge from your Game Boy, blowing on it and popping it back in

as we take you back to the 90s. Listen to Hey Dude, the 90s called on the iHeart radio app, Apple Podcasts or wherever you get your podcasts. Hey, I'm Lance Bass, host of the new iHeart podcast, Frosted Tips with Lance Bass. The hardest thing can be knowing who to turn to when questions arise or times get tough

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And a different hot, sexy teen crush boy bander each week to guide you through life, step by step. Oh, not another one. Kids, relationships, life in general can get messy. You may be thinking, this is the story of my life. Oh, just stop now. If so, tell everybody, yeah, everybody about my new podcast and make sure to listen.

So we'll never, ever have to say bye, bye, bye. Listen to Frosted Tips with Lance Bass on the iHeart radio app, Apple podcast, or wherever you listen to podcasts. All right, Chuck, thanks for playing along with me. We're gonna have like 50 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 and a couple of weeks is a new sort of divide has emerged. Everyone got together at first, it seemed like, and there was a lot of unity for five minutes. And then a dividing line has now formed 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 routes are, and we'll talk about specific examples of different countries and what they're doing, but there's elimination and then there's herd immunity and vaccinations. And not pooping. You don't mean pooping by elimination. No, I mean, getting rid of it 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 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 keep a safe distance from people, but bars are open, restaurants are open, no big concerts or anything like that. And let's try and get that herd immunity going instead of shutting everything down. Right, so they're pursuing a 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 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 of these numbers are gonna be changing, but the jury's kind of still out on whether or not

that's working in Sweden. As of a couple of days ago, they have a far higher infection rate than their Nordic neighbors. 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's still out. We don't know what our percentage needs to be right now. Like I said, it could be as high as 80%.

So we just don't know. As these numbers come in over the next month or two, it's gonna be really telling. I think kind of either way you slice it, it's not right to say, all right, we'll look at Sweden. And if it works there, that means it's gonna work everywhere because that's just not the case. No, and 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 to be successful at something like this because our population maybe is a little more collectivist than some other populations. They're healthier than Americans. They are healthier, they have a much stronger and more responsive healthcare system.

They have a more homogenous population, don't forget, which may mean that they could reach herd immunity more quickly than some other countries that have less homogenous populations. Sweden is more homogenous. They also get this, they also, they don't have like huge mega grocery stores where there's 1,000 or 1,500 people milling around

all at the same time. They have like smaller shops and markets that serve like a particular corner in a neighborhood and they have them like every few corners. So there's not tons of people in the market at any given moment. There's just a lot of differences between Swedish culture and say American culture

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 can't do this, we can't try this, this is stupid. And like you said, there are some early signs that it is not going so well because compared to Norway, Denmark and Finland, their death rate adjusted for population size

is between three and six times the death rate of those nations and those nations try to elimination. Yeah, and I saw that, I don't think it was like the, I think it might've 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 that it is as high as it's been. Right. And so Sweden's 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 and they don't have much of a choice. They're, they have like 0.55 hospital beds. So a little over half of a hospital bed per 1,000 people in the country and 44,000 ventilators. But both Sweden and India are taking a strategy of saying, if you're older, if you're elderly, if you are in this high risk group

for suffering complications from COVID-19, 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 healthcare system. 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,

but that's kind of like the mentality behind them. Yeah, and there are other countries, I think in England, they originally were gonna kind of follow that model. And then everyone said, no way, bollocks to that. And so they have got some stricter measures going. Belarus is the one place that's really, the president there who's been in office,

I think since 1994, 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. Oh my. And saying, screw all this. And Belarus has one of Europe's highest per capita infection rates.

Yeah, he's like, have any of you even seen the coronavirus yourself? I haven't. Yeah, geez, 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, LOL. And I was like, well, you're lucky, sir, you should be thankful for that.

And he was like, it's not luck, could be something else, dot, dot, dot. And I was just like, I'm stepping out of this immediately. Man, I don't know if 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.

This is another part of Georgia where I own a little tract of land. Oh, gotcha. So you need to make sure nobody's squatting on it. Yeah, I'm the only squatter that's allowed. So this whole herd immunity thing, herd immunity itself has been controversial since before the COVID-19 pandemic, right?

Those same people who question vaccines also question the concept of reaching herd immunity through vaccinations. There's like suspicion that you're artificially suppressing the vaccine and you're actually weakening the immune system and that it's gonna set us up for this horrible problem down the road. None of that bears scrutiny under logic.

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, we're going to opt to try for herd immunity now rather than later so that we can get our economy going again. What they're talking about is herd immunity without a vaccine.

Right, 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, hope we get to herd immunity sooner than later and a lot of people are gonna die along the way. And that's one of the big flaws of this argument of going for herd immunity right now,

which is there's going to be a lot of people who die as a result before we get to herd immunity because we don't have a vaccine. We're going to have to reach herd immunity through just exposure to this virus just like in the old-timey days. Yeah, I was about to say is if we were living in ancient times and just sort of crossing our fingers.

Right, not good. Lots of death is a big flaw against it. If the reproduction number for SARS-CoV-2 is three, that's confusing. But if COVID-19 has a reproduction number of three, let's say, and that means the herd immunity threshold is about 70%. That's about the high end that anybody's saying

is 70% should stop the virus from spreading anymore, right? So if that's the case, then that means 70% of a population would be sick. And I think a half to 1% of a fatality rate would mean that of the larger population, 0.35 to 0.7% of the population will die. So if you know that, then you can take just the populations of some of these countries that are trying this

and say, well, before you reach herd immunity, Sweden, out of your population of 10.25 million people, about 36,000 to 72,000 are going to die along the way. Statistically speaking, that's the number that you can bet on. Yeah, between 1.25 and about two and a half million in the U.S. And if you're gonna look at the world population,

we're talking numbers higher than the Spanish flu, 27 to about 54 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 I mean like this,

we're a virgin population, humanity, not just the U.S., 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. 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 bacteria, burn their way through populations like that. So you can imagine it would spread pretty effectively. And if the fatality rate really is a half to 1%, those numbers could be pretty real, depending on what measures we take to mitigate those, like you were saying.

So death, that's a big, big problem. And also along the way, we would be doing the opposite of flattening the curve by just letting people go out and getting sick to get things over with. Yeah, I mean, we 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 smaller towns

that didn't have enough beds and ventilators. And that's all been really, really sad to see happen. But by 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 and we'd be in that same, like in a worse situation than we were going in. Right, so that's another big one.

And then also Chuck, reinfection is another huge flaw in this. We don't know if SARS-CoV-2, which causes COVID-19, 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 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 create new strains. But with coronaviruses, 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 viable vaccine 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.

Tripop. Oh yeah, Chuck. I think he's just nailed it. Yeah, it's like a trip-hop band. For sure, that 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 head, the muffler, the thing.

I don't know. Yeah, you're on the trolley. So the other thing that we need to consider and that is the other sort of way that you can go about this is elimination, elimination that we were talking about. Not pooping. And not pooping.

And that is the opposite tactic and that's what most of the world has done, including the US, which is self-quarantining, isolating, trying to contain the virus, closing borders, masks, gloves, all that stuff. We have 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 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 who listen to those elected officials. Oh man, we're just gonna get so much mail for that one.

No man, someone come at me. New Zealand's prime minister is amazing. She's like one of the best. Yeah, I remember when we were there, we got a cab ride, you, me, and I did to the airport and this guy, I think he was an immigrant from Sri Lanka and he just could not stop boasting about how great the New Zealand government was,

about how taken care of their population was, how much of a sense of community the whole country had and it was just really refreshing to experience. Yeah, it is. 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 you move there if you love it so much?

Get out. And there's also Kiwis that are going, come on over, we'd love to have you. Sure. And then there's also probably some there like, please don't, we've had enough of you too. But 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 board in New Zealand and that's just not happened here. So yeah, I mean, it really has worked for New Zealand but they've taken serious restrictions. Like you can't fly if you want to domestically. They shut down their ports. If you wanna fly to New Zealand, TS for you,

you're not gonna get anywhere near the country. But in addition to that, if you're a New Zealand citizen, you can't fly from one place to another if you want to just for the heck of it, right? So they've really instituted some draconian measures but it seems to have worked. Like there was a report that came out two days ago on May 4th that says that the models originally used

to project how many cases New Zealand was gonna have said that they were gonna get something like 1,000 cases a day if they did nothing, like no lockdown measures. All they've had since March is 1,487 cases. Not 1,000 a day, 1,487 cases total and they've only had 20 deaths. So it seems like elimination can work

and for that reason, 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 government and culture that you have. But even without that, depending on that,

it requires that everybody act basically perfectly and avoid everybody else 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, we gotta find some other way.

Yeah and they've looked at, there are like ways you can look at the countries and decide whether or not people are gonna comply or not. There was some cultural data, there was a company called Hofstede Insights and they look at things like individualism of a population basically like whether or not people are gonna all go along or people are like, heck no, man, I want my freedoms,

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, they have a rank of 71 out of 100 as on individualism, the US scores 91 out of 100. So basically 91 out of 100 would be difficult to maintain 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 91 and thought, okay, that's a high score, there's a lot of individualism in the United States,

we got an individual streak like nobody's business, right? But if you look at it almost like 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 much of a sacrifice people have made. And 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 sacrificing for others is heartening. The problem is is people can only sacrifice for so long until you have just massive economic drawbacks and that's the thing.

So if you follow the forced herd immunity, natural herd immunity strategy toward COVID-19, you will, it will result in a lot of deaths. If you follow the elimination strategy, it results in a tremendous 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 you really should not understate the, the toll in human 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 depressed because they can't go out

and people dying by suicide and stuff like that, which, you know, I don't want to minimize that because 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 50 hours a week and commuting in a stressful environment and hectic crowds and mass consumerism and pollution

and everything else was like a mental health utopia. Right, yeah. So it's, you know, you 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 downshift in that manic productivity that drives most Americans,

you know? Yeah, and you know, here's the thing is we don't know, everything is so new, we're not going to sit here and pretend like there is only one right way. Like we don't know, 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 as we're driving on it or whatever that expression is. It's close. And, you know, I have my money on 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, it's still early and the data is still coming in. There was a report this week of 100 New York hospitals. They found that 66% of new cases were 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 all the stuff that we need to be doing to handle this pandemic, let's also create like a really robust data sharing 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 these social distancing guidelines

or they followed herd immunity pursuit. 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 in 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 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 mindset of, well, you know what, I'm pretty cagey and the weather's nice and I don't know anyone personally who's gotten it so I'm just sort of gonna ease back into normality here. I think that's when the second wave comes and things get worse and it's tough and everyone is antsy and cagey. Myself included, you know, I find myself wanting

to do things and it's tough on kids especially, but I think it's more important now than ever to keep up what we're doing. Yeah, we haven't just magically wished the pandemic away, it didn't work. No, and lovely weather, you know, take your walks, get outside, do it safely, but 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 and forth on this, but I saw a post that said easing of lockdown doesn't mean that the pandemic's gone away, it means that they have a hospital bed for you now. Right, exactly. You got anything else?

I got nothing else, man. All right, well, that's it for herd immunity, hopefully you guys learned something. I definitely did from researching all this and we hope everyone out there is staying safe and sane and hanging in there. That's right. Since I said hanging in there,

it's time, Chuck, for Listener Mail. I'm gonna call this thanks from England and a little shout out. Hey guys, 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 podcast. Hope your families remain 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. No, that was concise and beautiful.

But you're from England, so you're very kind. 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 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, often with equipment that's being reused when it shouldn't be and not gonna 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. He also says PS,

Torquay, we heard from a bunch of people on this. You mentioned the other week and I think the Agatha Christie segment, we would pronounce it tour as in tour bus and key, tour key. It's always fun to hear how everyone pronounces these bloody, silly towns over here. Kind regards that is from Ben Cleaver and Harrogate, England. Harrogate, Ben, that was such a good email

that we are now friends. That's right. Thank you for that. That was much needed, man. Thanks a lot for that and we will very happily shout out the entire NHS and especially all of the people who are out there on the front lines working

to save people's lives against COVID-19 or anything that happens to have befallen them. That's right. Thanks again, Ben. And if you wanna be like Ben and get in touch with us, whether you wanna tell us to stop being so political or you wanna tell us that you think we're great, it doesn't matter.

We wanna hear from you either way. You can email us by sending one to StuffPodcast at iHeartRadio.com. Stuff You Should Know is a production of iHeartRadio's How Stuff Works. For more podcasts from iHeartRadio, visit the iHeartRadio app. Apple podcasts are wherever you listen

to your favorite shows. How Stuff Works Works On the podcast, Hey Dude, the 90s called, David Lasher and Christine Taylor, stars of the cult classic show Hey Dude, bring you back to the days of slip dresses and choker necklaces. We're gonna use Hey Dude as our jumping off point,

but we are going to unpack and dive back into the decade of the 90s. We lived it and now we're calling on all of our friends to come back and relive it. Listen to Hey Dude, the 90s called on the iHeartRadio app, Apple podcasts, or wherever you get your podcasts. Hey, I'm Lance Bass, host of the new iHeart podcast,

Frosted Tips with Lance Bass. Do you ever think to yourself, what advice would Lance Bass and my favorite boy bands give me in this situation? If you do, you've come to the right place because I'm here to help. And a different hot, sexy teen crush boy bander each week to guide you through life. Tell everybody, ya everybody,

about my new podcast and make sure to listen so we'll never, ever have to say bye, bye, bye. Listen to Frosted Tips with Lance Bass on the iHeartRadio app, Apple podcast, or wherever you listen to podcasts.