100 Days Later: Mathematics of a Zombie Apocalypse

here's my thoughts on this. So when we start thinking about zombie apocalypse, it's easy for us to start putting ourselves in survival mode because we're thinking that black and white um view of Okay, I shoot the zombie, uh, you know, look out for bad people, and then look after my own I can do it. I can do this.

I can pull this off. However, any kind of zombie apocalypse is still essentially like the collapse of civilization, collapse of order, and I tend to have low expectations about my ability to survive that in any in any way, shape or form that would it would feel like a victory, right yeah. I On the other hand, so I used to work right where they shot the first couple episodes of The Walking Dead in downtownta tank ye right where the tank was exactly. Tank still there. They just keep

it up. Yet it is, funnily enough, it's active to you can shoot buildings down with it. No, uh but yeah at the and so at the time, like I was working on horror projects, and my collaborator E. C. Steiner, who we know from the show because he's helped out with monster science stuff before. Um, he and I put a plan together and he where we've got like some people in our lives that our go to, like if something like this hits, we get them. We put together a band, and we have a location, like a secure

place where we're gonna go. It's the might be the library downtown because it doesn't have any windows up until like maybe the fourth floor. Problem is, I just found out yesterday they instituted thumb print biometric authentication scanners at this library, So you can't get in unless your thumbprint is like in their database. So but that means that zombies with thumb prints they could theoretically, yeah, like if students had been turned into zombies, just marginally smart zombies,

which whole plans Yeah, yeah, exactly exactly. See. My my view tends to run more along the lines of Karma McCarthy's The Road, Uh, And so I envisioned my place in a zombie apocalypse being a daily struggle to see if I mercy killed those I love and then myself. I've told this on other podcasts I know, but have ever told you how I read The Road. I listened to it on audio tape while I was running and it, Man,

that was a depressing workout. Like it was like, I don't know, two weeks or whatever it took me to get through it during my daily runs. But it was like you just like running along and it's just everything was gray, everyone was dead. There was depression. You know, you've read the book, so I've I've read a couple of times. I have not read it since I became a father of this. So yeah, I don't know. I don't know if I'll ever be ready for that. It's good stuff, which leads us to why are we Why

are we talking about zombies? Well, today we're doing a sort of quick version of monster Science here where we're going to tackle to very They're called micro studies that came out of the University of Leicester. UH. A couple of weeks ago we actually posted these to our Facebook page. So if you follow us on social media, you might have seen these. You may have even commented on them. Some of the comments from those Facebook posts are gonna

show up in today's episode. But we we saw these, we thought they were interesting because they were along lines of what we do with Monster Science, especially what Robert has done in the past with the video series Monster Science. If you haven't seen it, I recommend go watch it on our site or on YouTube. But zombies come up quite a bit when we talk about very various parasitic organisms.

The Court accepts organism different different parasitic zombifying agents in our world, so zombies are very much on the plate here and stuff to blow your mind. So when a new study came out and grabbed the headlines, we figured out we should cover. People really gloamed onto this one way or the other. They either loved it or they hated it. There's a lot of you out there who follow us on social media said please do an episode

on this, So that's why we're here. But a lot of people too were like, this study is bogus and here's why, and we're gonna talk about that as well. Um, but I'd like to start off, what what what are your favorite zombie films? Like, let's let's establish some ground rules. There's a lot of zombie entertainment out there right now, and it's funny, like I was looking at sort of the gamut of all of it, and I forgot about some really great movies. Will you go first, Well, what

are your what are your favorites? Well, my favorite is twenty eight Days Later, So so that's the wonderful one. That's the one that scared me the most, and I and I really like it, like both in terms of story and how it shot the most. Um. In fact, I got this really great poster at New York Comic Con last year by the artist Jacque and it's just a big landscape picture of the main character walking down a road that's totally abandoned in London, and it's really

evocative and you can get two of them. The second one it's the same thing, except for there's a horde of zombies chasing after him. But I prefer I prefer the lonely walk. Yeah, that was a great film, especially the I would say the first two thirds of that film are just just very difficult to beat in terms of zombie cinema and there, of course, people are split on this. There's some there're some zombie fans out there and say, oh, fast zombies not a zombie film. They're

they're probably cursing us right now for even bringing it up. Maybe, but it's actually the zombie slow zombie argument is going to be important to the science today. I will come in and say that one of my favorites is actually a fast zombie film and that is a dead set. I haven't seen that. What's that? Yeah? Dead Set? This was a two thousand and eight British kind of a mini series and it was created by Charlie Brooker, who of course everyone is now familiar with because of Black Mirror.

But this one had fast zombies in it and had to do with the cast of a big Brother uk Um not being aware that the whole world is is falling into zombie chaos. And that's a brilliant premise. Yeah, and it sounds like it's going to be a comedy. I went into it. This was this It wasn't available

in the States at the time. I think now it's on Netflix, but at the time you had to get a like a pirated copy, and so I obtained it, and I was telling my wife it's like, oh, I got this new comedy but about these reality people, reality star people and their zombies. And we're like, oh, that sounds great, and we sent out to watch it and it is terrifying. Yeah, yeah, it's it's a great it's

a great, great zombie film. But the fast zombie thing is interesting because when it came out a lot of people were criticizing Brooker's use of the fast zombies, including

Simon Peck. He came out in one of the of Shaun of the Dead came out and was criticizing it, and Brooker basically said, look, we didn't have the budget for a horde of zombies, and if you don't have the budget for a a full mas of zombie flesh, you've got to make the most out of individual zombies and the best way to do that is to have them run really fast, and you play some Aphex twin over it, and while you've got some dead set so wait twenty eight days later and probably what the remake

of Donna the Dead were like, the two big fast zombie movies like the start of that, I guess. So though you do see some fast and semi fast zombie movements in other films as well. Yeah, one of which I'll get to in a minute. Well, the original Donna the Dead is one of my favorites as well. The zax And one is fine, but I really have a soft spot for the original one where they're i mean both of them, they're in a mall. But it's just, um,

everything that's great about zombie cinema. Right, it's not about the zombies. It's about like the themes of humanity and what happens to humanity as a microcosm in the middle of this crisis, right. Yeah, Like basically the idea of this one is that you have a some survivors and they find this shopping mall that has been untouched. I mean, there's zombies in it, but nobody's looted it. It's it's like a little paradise. Yeah, and reminds me a lot of a Michael Caine film that came out I think

before this, called The Last Valley. I believe it's Uh. He's a general and it's uh and they end up him him and his troops end up finding a valley that's untouched by I want to say it was the hundred years War, but it's been a while since I've seen it. Okay, huh, that's interesting. Yeah. I think stories like that now get like, why don't we throw some zombies in there? That'll that'll sell it a little bit better. Yeah. Well,

I mean it's it's not a bad strategy. Like instead of saying zombies first, now, let's find a now I need a craft a story around it. Go ahead and steal a good story from somewhere else and sorrow a good story. Add zombies and you've got something new. And that's kind of the theme of the studies that we're going to talk about today. Some other of my favorites are I don't know, Shaun of the Dead. You mentioned that's a great one just to pull out every once

in a while and have a good laugh. I really also like uh for funds, Knight of the Creeps and the Omega Man, the Charlie Omega Man. Uh, And Pontypool was one that popped up I had forgotten about as a great zombie film. That's just really small, low budget smart movie. Yeah. Um one that one more that I want to mention. Well, I'll mentioned just a couple in passing.

I'm a big fan of some of the Lucio Fulsey Italian zombie films, like The Beyond to a limited extent The House by the Cemetery that there's only one undead creature in that and he's more of a mad scientist. But one of the best that I would I would just be remisfected to mention is Return the The Return of the Living Dead. This one was directed by Dan O'Bannon. Wow. Really, Okay, you were talking to me about this beforehand and I

didn't know much about it. But now that you've said Dan O'Bannon, I have a much clear head idea in my head of what what this is going to be, Like, Oh, yeah, it's it's Dan O'Bannon. Maybe the crankiest person in any of the Alien behind the scenes interviews, Like if you ever watch any of the like DVD extras where they talked to Dan O'Bannon, he's just not a happy camper. Well he luckily for us he did. Uh. He did have a role in some some pretty cool films here

and there, and this is one of them. This this is a zombie film that it's fun, it has it has some some gore moments, some wonderful zombie effects, but the zombies talk, the zombies eat brains. It's it's faculous. I think he had something to do with Life Force too, didn't he the Toby Hooper one, Yes, you wrote the screenplay. Okay, yeah, I mean he was involved. That was right after this,

So yeah, Alien, Blue, thunder Dead and Buried. He's had he's had his hands Carpenter on what was Carpenter's first thing. They worked on something together. Anyways, So you know you're probably wondering, well, why are you guys nerd ing out

about this? Stop nerding out. Well, one thing that we're actually starting to do along with some of our episodes, and you may be familiar with this if you follow us on social media, is, uh, we're trying to do every couple of Fridays a Facebook live event where we do trailer talk about the science that we cover in the podcast that week over movie trailers that are related

to what we're doing. So probably uh, this week that we're recording this, so those of you who are listening that this will have happened in the past, but we'll do a zombie trailer thing along the lines of this episode. It will be on our Facebook and you can watch. It will be Robert and I talking over trailers, basically applying what we what we learned here today and what

is that. Well, so this is the general idea here seems to be and this isn't just the University of Lester, but it seems to be using theoretical zombie science to teach the public about the importance of public health and disaster preparedness. Um. Now that the university's press release for the specific thing that we're going to talk about today, they say that their science Topics module is trying to add a sense of humor to teaching sound scientific principles

to help communicate science to the public. Now, I have to note here, though, there was a huge disclaimer from the university at the top of the press release to make sure that everybody knew that the release didn't actually, uh like represent the institution's views. Uh. And I find that funny having formally worked in academia. I'll talk a

little bit about that later in the episode. But basically, they've got this undergraduate program, and these undergraduates are assigned to write and critique and publish their own research papers in a group. Uh. And they apply the scientific principles to phenomena from things like pop culture or everyday life. So you get these zombie studies, you get, um, something similar to the episode that you and I did on vampire physics and stuff like that. The purpose isn't to

actually learn zombie science. The purpose is to teach these students in the public that's reading their work about how scientific principles can be applied in the real world. So it's it's really a communications method. Yeah, and for the most party tends to work these studies, and this was not you know, like you said, this is not the first study to do this. They've been a few different

that have tackled zombies, vampire one. I don't know if there's been a werewolf one or one that tackles Frankenstein's right, but somebody get on a franken staff, how how how do frank Stein's spread? Let us know, um, But but you know that these are the studies that do capture public attention. They show up on stuff like the Colbert Report, So it's yeah, it's worth it's worth keeping. They're worth

doing in my opinion. So the papers, the way that it works is they're openly published in the university's own online journal, and this is an open access journal that anybody can read, and they're scrutinized at the same level that you know, regular academic papers would be that are published. They encourage these undergraduates to have a realistic introduction to how difficult academic publishing and peer review is, and it prepares them for a career in scientific research. Uh So

they introduced this their department. It's actually not that new of a thing. They started doing this in UM. Of course, some people have criticized them for taking trivial there. They say they're trivializing science, and they also say that they're wasting public funds unquote zany non topics. The scholars who are running the program actually argue, well, it's more about the communication and teaching than it is about the actual research.

Now this is where I'm going to talk about my own experience here UM with this type of thinking in academia. So I've mentioned this before, but I used to work

at a state university here in Atlanta. I was in public relations there, so part of my job was to get people interested in the library in particular, and while I was there, they there were a couple of instances that popped up that were like this, and I saw firsthand the gnashing of teeth of these academics who saw, this is trivializing what we do, This is such a waste. One of them was that the library wanted to do like a zombie gag kind of video trailer, uh, that

taught people how to use the library. So like the gag was like students were trapped in a study room and there were zombies all around them and they needed to use like library resources to to get help, right. Um, stuff like that. Also around the same time, and you and I talked about this the c d C. This was in two thousand nine, the CDC started this public

advocacy program where they did a whole thing about zombies. Uh. The CDC is based here in Atlanta, and I mean, I guess I think it's it's safe to say a lot of the universities here feel like a sort of affinity and connection with the CDC and that it represents them somehow. And man, did I hear people complaining about that, like, oh, what is the CDC doing? This is such a waste

of time. And it was the same effort. Basically, the idea was like I think they had like a zombie kind of like preparedness guide or blog or something like that. It was silly, but it was the idea wasn't like, hey, zombies are real. It was Hey, we're the CDC, We're real. You should know about us, and like maybe if you come and you take a look at this stuff, you'll learn about what we actually do. Yeah, I mean the criticism here also reminds me of the critics of the

Ignoble Prize. You have in the past said, oh, well, this trivializes science. You're high you're you're making fun of science. You're you're highlighting studies that aren't important, that sort of thing, And yeah, I think, uh, those tend to be just a few outliers for the most part, I feel, but I think it's obviously more about just having fun with the topic and generating some attention to to the to these particular studies that are in the case of the

Ignoble Prizes, and none of them are ridiculous. We've we've covered them before on the show two years running, where we really highlight that, yeah, each of these studies actually is doing something of scientific importance. It may not be, uh, it may not be curing cancer, and it may seem a little bit shrimp on a treadmill to you, but it's all part of the scientific effort. Yeah. And in my experience, like most of the people who get upset about this are are old guard academics who you know,

it's threatening to them. They feel like it's threatening their routine. It's just, you know, I think, a regular kind of cyclical thing that happens in academia. And you do see other outlets engaged in this sort of thing on a regular basis. For instance, the British Medical Journal, they put out a Christmas edition every year where they play around

with the format a bit more. And in two thousand fifteen they actually put out a paper Zombie Infections Epidemiology, Treatment and Prevention by Tara Smith, Associate professor at Kent State University in Ohio. And this was a tongue in cheek article that that explored the idea of a zombie outbreak. Yeah. Yeah, And so we've got a lot of stuff like that out there. I think if you've heard about it, like we've heard about it, and you've seen them running on sites like I think I first saw it on Live

Science and then actually here at how stuff works. We ended up running an article about it. Um. Uh. You know, I see it as like this is a great way to get people interested in communicating about actual, real life public health issues. Um. And it's interesting we saw that in our Facebook thread and so some of those comments I want to bring into it today after we go through these studies, because there was a lot of a lot of react is a lot of arguing that was

very logical. But if they had read the studies all the way through, I think most of their questions would have been answered. And not to mention, this kind of project really speaks to our own mission here. It's suptable in your mind what we try to do with the show as well make science accessible and fun Alright, Well, on that note, I think maybe we should take a quick break and when we come back, let's jump into the study and talk about exactly what it consists. Off. Okay,

we're back. So there's actually two studies that were done here at this at the University of Leicester, uh. And the students that were involved. Their names were ct Davies, kJ Cheshire are Garrett Lee and Jay Moore, and they used a real epidemiological model to figure out how long it would take zombies to wipe out humanity. They did two studies, the second of which concluded that there would be less than three hundred survivors remaining after one hundred

days of a zombie outbreak, So there's some hope. Uh, And I'm I'm tentatively calling this a hundred days later because they're using them basically like what would what what would it look like? Specifically a hundred days after the outbreak? They assumed the following in their study. The first was that a zombie can find one person each day, and the second was that a zombie has a nine chance

of infecting their victims, which seems pretty high. By day one hundred, they calculated there would only be two hundred and seventy three remaining humans, with a million to one zombies to that, so there would be two hundred and seventy three million zombies. They considered that the probability of infection would actually become less realistic as the zombie to human ratio increases, so that that will be important later because that was a common complaint of some of the people.

Would just be harder for the remaining humans to be infected because there would just be too many zombies too few humans, and the humans that are left are probably hardened to the realities exactly like we see on Walking Death, Like, if you're by the later seasons, you should know when to reach into the zombie horde with a hammer exactly. Yeah, yeah, you've developed the necessary skills. So the model they used

is a real model. That's called the S I R model, and it describes the spread of a disease throughout a population. It considers the rates at which infections spread and die off as individuals and the population come into contact with each other. So this seems like an important thing that we should, you know, have a basic understanding of. It

splits the population into three categories. The first is those who are susceptible to the infection, that's the S, those who are infected that's the eye, and those that have either died or recovered, and that's the R. It's considered the rates at which infections spread and die off as individuals in the population come into contact with each other, and it's defined by three equations. There's a bunch of math in this. I'm not going to read out like

sigma whatever to you. You know, you can go look at these if you want to. They're readily available online. Um, but we want to make this accessible to you as well. The team here they re christened the s R s I R model as the s z D model because because the z I infected are their zombies and are is actually they're dead, which includes both dead zombies actual dead not undead, and and dead people. Uh and this

reflected susceptible zombie and dead categories. Now, a constraint of the model that we should note is that each person in it moves from being susceptible to being a zombie to being dead. This model does not account for simply

going from being susceptible to being dead. Okay, so doesn't account for ways that human beings could die other than by being killed by a zombie in a zombie apocalypse, which, as we've seen in all kinds of zombie entertainment, more often than not, your fellow humans are even more dangerous than the zombies are during crises like that. All right, So here's the first study. It was called a zombie epidemic, and it did not factor in the following natural birth

or death rates during this hypothetical epidemic. They assumed that over the course of a hundred days that these would be negligible compared to the impact of the zombie virus within that time frame, and their calculations suggested that with an equal distribution of global populations, the human race would get totally wiped out. Now another thing to consider here is their calculation had estimated a zombie outbreak as being

roughly twice as contagious as the Black Death was. So they had they had to have some basis point basically to to set up what their numbers would be, right, So they looked to it's the closest thing we've had, and they saw Black Death and said, let's use that. In addition, they estimated that a zombies lifetime would only be twenty days before they starved to death, basically and

rendering them effectively dead. Now this brings to mind, like some of you out there going well, zombies are already dead. Why would why would they need to why would they need to drink? Right? It reminds me of the end of twenty eight days later. Uh, where the zombies you know they crave like coming into contact with people. In that case, they're like rage zombies but but they do they need to like consume energy the same way any other being does, and so like they run out of steam. Basically,

that's the question that always comes. But from me when I watched The Walking Dead? At what point do you outlast these things that right that they're they're standing there, they're rotting, They're reduced to skeletons. You've got to think if they're craving flesh or brains or whatever, they must need it for something. It's probably fuel the same way that like we crave food and water. Yeah, do they do they put out heat? If not, then they must

be freezing during the winters. Uh. And if so, that's going to damage the tissue even more. I mean, you can go on and on picking scientific calls in the zombie myth. Another aspect of the study was factoring in the rate of the infection and how it would spread across geographical boundaries. So to do this, they added to the formula as a system that prevented a very low amount of zombies being able to start an infection when

a regional population was much higher in proportion. I think, like for example, they said like point ten zombies versus like a hundred humans, it would be totally unrealistic for the zombies to really do anything, right, the numbers have to sort of come closer to one another in terms of population. However, this assumes that the global population is evenly distributed across the regions that are all adjacent to

one another. Right, So they're basically like, let's say it's county to county that like, there's fifty people in each county, right, even though like in real life, our populations are much more diversely and spread out. So that basic model in the first study found that it would take twenty days for the infection to spread to a noticeable fraction of

the population. Once that happened, the remaining population would be quickly overtaken, with only a hundred and eighty one survivors versus one point nine times one hundred and eight zombies

after a hundred days. But if you stagger the infection due to geographical segregation, and I think what they're talking about there is what I mentioned earlier, like that there would be a variety in how many people would be in each adjacent area to the I guess h ground zero for this, then they would have two hundred and seventy three survivors on day one hundred versus one point nine times one hundred and six zombies. But still a shred of hope. Yeah, little, I mean, you've got yeah,

you've got a couple of people. What they didn't do is extrapolate how much longer out it would take for those, you know, two hundred seventy three people to be overwhelmed by the one point nine times on SI zombies. But there's a little bit of hope there. Yeah, maybe if you hold up, if you follow my plan available online. Now. Uh So, they recognized that there there were some flaws in this study, right, as you know, as we'll find

a lot of people pointed out to them online. Uh So they did a second study, and they called this another zombie epidemic, and they introduced parameters that allowed for the zombies to be killed and for people to have children during a zombie apocalypse. Now, this made human survival more feasible, and it suggested that eventually the zombies would be totally wiped out and humanity would recover for reproduction. They assumed, and this was kind of wild to me.

They assumed that any given half of the population would be able to pair up and reproduce, and they gave birth to one baby every three years. They acknowledged that this was unstable if we had a population level like our current one, right, but they said it was suitable for their purposes since the population was so small from

the zombie devastation. They also factored in that half of the population of the susceptible people would be female, and half of those females would be able to bear children. So I mean, okay, they're they're just kind of going with some averages here. It sounds like to me. Yeah, Now, of course, I know a number of people were thinking out there, these children are going to be nothing but a liability until at least Oh, I don't know what's a good zombie fighting age. Yeah, I mean from the

I guess the Walking deads are best. Example. Carl like starts off at like, I don't know, eleven or twelve, and he's probably like fourteen by the time the show is currently up to play. Yeah, Like, I'm trying to think of, like TVs Trust to Kill Zombie. Could could Opie have killed children? Have not killed children? Could Opie have killed b could definitely have killed children? You know, Um, Yeah, but you know, you know what I mean, It's like, at what point are they actually gonna be able to

contribute to the survival effort? Hear? I wonder if it's a sort of along the Lenes what we were talking about in our expense episode in terms of like the ages for draft ability for warfare. But I don't know. I theoretically, I guess high schoolers would be great. I mean red don Yeah. But hey, that also reminds me

of my favorite zombie movie, Night of the Comment. The two girls in that are high school aged girls and they do a pretty good job, but their dad like taught them how to shoot doozies I think, or something like that. Okay, back to this study, and they had some other parameters to to try to make it more quote realistic. They altered the infection probability to vary as the system evolved, accounting for survivors being able to kill

the zombies and considering the population the reproduction rate. So they also extended the lifetime of the zombie from twenty days to one year to make them more formidable. I don't know what the rationale behind that was. What do you think I mean, twenty days seems like a legitimate time for okay, assuming a zombie needs to eat to keep cruising along and not just fall apart. Twenty days sounds reasonable to me. That's longer than you and I could go. Yeah, I guess you can make a case

for either one. And it's one of those situations where if you start trying to pick it apart, it's kind of fall apart pretty easily. A year seems long to me. But then, like you know, most of our zombie entertainment, you see zombies that look like they've been totally rotting away for longer. Yeah, I mean it. It raises the question, is this the creature continue to rot because it's are it's muscles contributing to its movement or if there's some

just how supernatural is the effect? Exactly? Good call? Okay, Well, when they introduce this, it'll loud for the rate of change in the zombie population to change by the rate at which the susceptible population could kill them, So there's some more fluctuation and variety here. It also increased the rate of change of the dead population by the same amount,

so that kind of makes sense to write. Is that like that as they're killing off zombies or as the zombies are dying from hunger, or as the people are dying. Theoretically that the dead, the number of dead would pile up. Now, with these alterations, the students found that it was more likely that humanity would survive a zombie apocalypse under these constraints and could wipe out the zombies after one and three days. So that seems significantly better than what we

got last time. Last time it was there was a glimmer of hope, but it seemed pretty daunting. Now here's my question. We talked about this earlier. Fast zombies versus slow zombies. There's no in these papers, there's no definition of what kind of mombies we're talking about here. Okay, I'm gonna assume they're fast zombies. An probability of infection rate seems really high to me. I mean, if those were slow zombies, then what would the infection rate of

a fast zombie like or something? Yeah, I mean, based on just our viewing of various zombie films, that for the slow zombies, you're you're really only in danger A in the in the early goings and you don't know what's up B when there is a very high population density of zombies. You're dealing with zombie horde, and maybe

you're factor into a constrained space, urban environment, etcetera. Uh, and beyond that, just like sheer human stupidity, right yeah, which granted, never, never should we we underestimate pure human stupidity, students stupidity to get in our way of survival. This is true. Watch any episode of The Walking Dead for further reference. Uh. So yeah, I mean I'm going to assume that they're fast already, but I'm curious what you

guys out there think. Okay, let's take another break, and then when we get back, we're going to talk about the commentary that surrounded this, at least for us, and then we'll look at one more zombie study. All right, we're back. So, yeah, you belief you were the one who shared the original study on Facebook. How did folks react? Well, it was very popular. I mean, we pay attention to our our Facebook metrics and we see what succeeds and what doesn't. It help us. It helps us to choose

what to talk about in the future, right Uh. And it was extremely popular, but several people took issue with the student's methodology, though not all of them seem to have read past the headline or the first paragraph. So for me, I was considering, like, what their mission here wasn't the zombie research, it was the communication. Like if we go back to what what their actual goal was here,

Let's remember these are undergraduate students there. I'm presumably the same age as we would be here in the United States, like eighteen to twenty two years old, um, and that the goal was for them to learn what it's like to put their research out there in the world and then to have it hacked a bits, right, And I thought it was an interesting lesson in terms of that,

especially in terms of consumption of digital media. I'd also argue all these comments showed that the university's campaign to get people to think about public health we're pretty effective because as as uh, you know, interesting and kind of argumentative and pedantic at some as some of this stuff is, it got people thinking about public health in a logical way. Yeah, you know, the arguments that they make are things that we're actually addressed in the study. So here's one of

the first ones that I pulled. Somebody on our Facebook said this about the study, except there are some very bad assumptions In their model, they basically assumed that people the most powerful predators on Earth won't or can't fight back. Now that's something that they address in the second study.

They ignore travel time e g. It's going to take a long time for zombies to swim to continents and islands not connected to the one where the outbreak starts if people are smart enough not to fly them there on airplanes, etcetera. That's true, But they do also address the geographical adjacent population density, which I think was their attempt to tackle that. And of course, the zombies are

going to run out of energy stored fat, etcetera. Before they cross an ocean unless they're really good at grabbing fish along the way. They also tackled that right and that they gave the first study they had the twenty days limit and then they had the one year limit

in the second study. Yeah, the the energy argument, I feel, is one of those that it's it definitely blows a hole and pretty much any zombie idea, So it's kind of it's kind of out of out of the box for the thought experiment, like where where is the first couple of points that this person raised our are very much in keeping with the thought experiment. Yeah, it's exactly. It's like breaking the premise. Yeah, because I can't I can see the validity here and saying you know, woulden

people fight back. Now you can make some arguments to say that, hey, we we can look at real life threats and help. People often fall back on normalcy bias. They just they just assume this can't be happening, and they have trouble actually reacting and readjusting to to the new set of circumstances and the danger they're faced with. So, you know, I think we can go either way on that.

And as far as zombies traveling to other places, certainly, the the idea of a full blown zombie being permitted to board an airplane by T. S A is uh what is hilarious and and maybe not practical. But but the idea of an infected individual, certainly in a time of chaos, is trying to flee to different places. Did you see World War Z? Wasn't that like a big plot point in World Wars? I think I did not see the movie. I read the book and really enjoy it.

So I remember a scene where there's a zombie that was like trapped in the landing gear or something like that, and like a stewardess goes and like opens up the thing to figure out why the warning alarm is going off. And those are fast zombies and like basically like the infected. You have this instance in that movie where that one zombie infects her and then just like this wave of people getting infected moves from the back of the plane

toward the front of the plane. And it's like worst case scenario right where you're on a plane and just like there's no way out. What do I do? And spoilers for World War Z, I guess, but like I think what happens is like they crash the plane and somehow Brad Pitt just like lives through a plane crash. Um, I you know, I take you back. I think I did see the movie, and the only thing I really remember is that they did have a very not only fast zombies in terms of their speed, but just fast

in terms of the infection. Like you could see the infection spread from street to street. And remember they could like they moved like waves. Right, there was some kind of it wasn't there even like a scene where that like the zombies were sort of like ants, like a hive and they would like pull helicopters down and stuff.

It does make me realize that one of the advantageous things about using zombies to study the spread of infectious disease is that despite the fact that we all know what diseases are essentially, you know, we experience illness, we know how these things work, we know to wash our hands,

these are still kind of invisible forces to us. And the zombie makes the invisible visible, and therefore we're maybe a little more inclined to engage in in these thought experiments, and then perhaps the residual knowledge will be useful in thinking about actual legitimate diseases. We'll give you an example that's pretty grounded and close to home for us. A Bola. Yeah, so the c DCS here you may remember, like, what was it like a year a little over a year

ago when there was an abola scare. We had some doctors who were infected with a bola brought back here to Atlanta, and they were in a public hospital, not in a CDC hospital, quarantined to be taken care of for this, and there was huge concern throughout the city of oh They're bringing this infection to the city, We're all gonna die. There's gonna be a huge bowla breakout. And I remember just thinking like, well, clearly a lot of these folks aren't educated on public health and transmission

of disease and how a bowler works. But like, well, and people get emotional, paranoid and paranoid yeah about things that threatened them. Yeah, absolutely, Uh but you know it kind of makes you think, like, well, maybe if we all just sat down and walked through the S I R model, maybe maybe we've did that on CNN instead of some of the stuff that's on there, we would have a better understanding of what the likelihood of it

of a traveling was. Right. Anyway, back to these zombie questions. So, okay, the second one was another comment on Facebook, and this person says, yes, but this study is super flawed. Is zombie wouldn't have a nine chance of infecting someone every day forever? Maybe the first weeks, but after that, I

know the percentage would stop would start dropping. Now, again, that was something they addressed in the study that they They definitely said that they accounted for the fluctuation at least in the second study of whether would hold because as we as we mentioned, right, like, if once you reach kind of a saturation point of zombies, they're not really that many other humans for you to be able to infect, so that rate's going to go down. So they did address that, um, and that's that. It's a

good point, but that's part of the study. Alright. Third one here, the numbers here just don't make sense. As the human population dwindles, so would the chance of a zombie encountering a human. And you really can't predict stuff like strategy, preparation, et cetera. Chances are there's going to be a few communities scattered across the world that adapt. So same thing they're basically arguing about, right, Yeah, you can't account for things like strategy and preparation, of course not.

But this is a model, you know, it's it's not predicting the future. But at the same time, yeah, nine seemed high to me, you know, but basically the math works out either way. Right, If you just change nine to another number, you would it would just spit out different results, right. Yeah. And then the last one was what we've talked about already. Somebody said zombies would last less than forty eight hours because of phenomenon called bacteria that would eat them up. Well, again, I think that's

totally fair, but it breaks the thought experiment. So it's it's we kind of have to dismiss it, even though that is again one of one of the most valid criticism the idea of zombies. Think we even have an article on how stuff works that Joe adapted into a video that it's something along the lines of like five or ten ways why zombies would never work, and that of course is one of the very first ones. But

you're breaking the premise of the thought. Yeah, so I I would just say, like, if the project was designed to teach these students anything, I think it taught them how to have thick skins while people pop out of the woodwork and I tell you what's wrong about something, and I guess what. Welcome to academia. That's totally what it's like. Well, welcome to U speak and social media too. You don't have to be an academic to encounter people

who don't read the entire article. But if or have legitimate issues with the study, I mean, that's that's part of it. We we stuff to about your mind. We we invite everyone to to give their their take on a particular topic or you know, criticize it, what have you. Yeah, and you know, the way I was taught at least was that like, when you are going through the rigors of preparing a study like this, you should be prepared

to defend it in a public forum. And honestly, based on all of these criticisms, I feel like these students did a pretty good job. I'd give him an a. You know, there are a couple of weird things here and there in the paper, but like, for the most part, they did what they're supposed to. Now, I do have to to point out that there was a study that came out in two thousand nine that covered basically the

same territory. This was a titled When Zombies Attack Mathematical Modeling of an Outbreak of Zombie Infection and this was by months Hudiya Ammad and Smith from the School of Mathematics and Statistics at Carlton University. And this was published in Infectious Disease Modeling Research Progress in two thousand nine, right around the same time that the CDC was doing it. That maybe that was our peak zombie zombie science. Yeah,

so this is a really cool study. It's actually available online I'll try try to remember to include a link to it on the landing page for this episode, because a lot of it, I'll of it breaks down into equations and these different models, but I'm going to just give you the high level of how it, how it flows together, and you will definitely notice some similarities between their approach UH and UH and the approach in the

previous study. So they first defined as much of a generic pop culture zombie as possible, you know, falling back on the slow zombie factoring in just the basic mundane stuff, not going with the more fun stuff like the idea that they can talk and they only eat brains. I'm awaiting that step like a reanimator kind of zombie. Oh yeah, and how can we forget reanimated? It's a tremendously fun zombie. Um.

So they busted out the model along three basic cases. Susceptibility, s zombies, z and removed are very very similar, yeah, like one letter difference. So these three classes are then used in equations to spell out how zombie human interactions lead to zombie removals, death and resurrection as zombies, etcetera. Then they revised the model to include latent or infections, the idea that you'd be bitten and then you're infected for a while and then you turn into a zombie.

Then they factored in a model for treatment and essentially, you know, curing it. They model though the effects of partial quarantine of zombies. Uh. Then finally they factored in impulsive eradication as they put it into the mix. What is impulsive eradication? It sounds fun. Just kill the heck out of So it's like, yeah, it's like one of those scenes like where somebody just goes in with a sledgehammer and machetty and yeah, yeah, okay, just destroy our

zombies especially uh. And it's all very equation based. Um, you can look at the study, but unless this is your thing, you're going to get as much out of it as I'm describing here. But but here's what they decided in the end quote. An outbreak of zombies infecting humans is likely to be disastrous unless extremely aggressive tactics are employed against the undead. While aggressive quarantine may eradicate

the infection, this is unlikely to happen in practice. A cure what only result in some humans surviving the outbreak, although they will still coexist with zombies only sufficiently frequent attacks with increasing force will result in eradication, assuming the available resources can be mustered in time. So also this is kind of interesting in comparison to the previous study. They say the longer the time scale of the of the outbreak, the higher the likelihood of complete human extinction.

I think. I think if you took the math and you pushed it past a hundred days, I bet that study would have found the same thing. Okay, they said that the key difference though, between this model and other real world infectious disease models, like, really the only key difference is the resurrection of the dead. Otherwise you're talking about the same variables that play into considering the spread of uh, you know, of plague orrible or what happened.

But they said, as far as the zombie scenario, if if these fictional creatures were to suddenly rise up against us, they say, hit hard, hit often, that's the only hope. Well, I'm really impressed that they added the idea of a cure in there. I don't think I've ever seen that in any zombie fiction. I want to say that it was I remember watching all the special features on a Man Well, Mega man. And of course some fans are probably gonna criticize and say, technically, that's a vampire film,

but it's kind of a hybrid, to be honest. I want to say that when I watched the special features for Twenty Days Later, there was originally a different cut for the third act, like, oh, the only story boarded it. They never filmed it, but it involved something about a cure or a possible cure, but they ended up deciding it didn't work. I remember hearing about this that, like the idea was that the gym character would be infected at the very end and they would be trying to

cure him. Yeah, and they're like having a conversation with somebody on the other side of the door. I found it really interesting, especially since, like I said earlier, I'm less in love with the third act of the film. But I mean third acts are often difficult in films. That's a that's a third act. That's like a happy ending third act. And I think the other ones that

they had planned would have been like like real dour. Yeah, I think this one was more dour, but yeah, we don't see the cure for the zombie plague invoked a lot no, not really. Well, maybe give us examples if you if you use some of you out there are going no, it's in this or whatever. Well, I mean it was kind of a there was a false idea of a cure in The Walking Dead, right, yeah, yeah,

there's something like along those lines. And I think they frequently run into characters who refused to accept that they're undead, and so they like are hoping that they can cure them and they'll come back. Well, here's here's the thought to sort of close out on here. I guess it has been people have commented before that you see this, You see zombie zombies have never gone away. We've just

continually are into zombies. But they say that there's this relationship between political power in the United States and the popularity of zombies, uh and or vampires. I heard about this. They say that if you have a Democratic president, then vampires are in, and if you have a Republican president,

zombies are in. So if this holds true at all, I guess we can expect to encounter even more zombie fiction over the next four years unless you classify President elect and I guess at the time this publisher's President Donald Trump as something else, and both supporters and opponents have certainly framed him as such. So maybe we're going to see a new craze. Maybe it'll be mummies, maybe it'll be uh fish people. That Mummy movie is coming out next summer, And man, didn't we talk about this.

They're they're remaking Creature from the Black Lagoon in theory. I don't. I have not checked in on the project to see where it stands, but that's one that's been I mean, they're they're relaunching the whole Universal Monsters shared universe. I think the Mummies the spearhead for that. So maybe that'll be and I would I would love to see that. Would be something positive to come out of the next

four years. For sure. If we see just Gil people take over of Gil People, moving shadow over in Smith comes in the full full swing as a as a motion picture, I'd go for that. I'm down Dagon. Yeah, great movie remake of Z a K. Blood Water is the Doctor Z. So to close out, I have a question for you. If I was bitten and you knew I was gonna turn, would you kill me? Would you be able to do it? Or would you just like lock me in the podcast studio. Mm hmm, that's a

tough question. Um, I guess I would. I would lock you in the podcast studio, but I would I would make sure, I like put a lethal amount of snacks in here or something, just so you could you could make the decision for yourself. That's nice. And yeah, like I would just eat myself to death before that's very likely. Well, those of you out there, let us know, would you kill me if I was bitten by a zombie? Uh?

There's places that you can let us know, or you can let us know more about what you thought about. These studies as well are the effective communication tools for science and public health. We're on social media on Facebook, Twitter, Tumbler, and Instagram. We also have a lovely home site, stuff to Blow your Mind dot com. Yeah, and if you want to send us an email get in touch with

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