Preparing for the zombie apocalpyse

I have a paper out in the Christmas issue of BMJ on the coming zombie apocalypse.

You read that right. And yes, it was peer-reviewed.

I’ve discussed previously how I’ve used the attention paid to zombies to talk about infectious diseases with children and other audiences; and to bring some science to the Walking Dead and other zombie tales. I even include a zombie lecture as part of the talks I give in my position as an American Society for Microbiology distinguished lecturer.


Like them or hate them, zombies are part of the zeitgeist. The Walking Dead is still one of the highest-rated programs on television, and its spin-off, Fear the Walking Dead, has been renewed for a second season. Early 2016 will bring us Pride and Prejudice and Zombies on film. Even Aaaahnold Schwarzenegger did a zombie movie. The Girl with all the Gifts was a sleeper hit, and a movie version of the zombie fungus video game The Last of Us is supposedly on the way.

So that’s what the BMJ paper was all about. Of course, it’s ridiculous at its core–no one really expects a zombie outbreak. *But*, we do see new diseases emerging all the time. MERS. Zika virus. Chikungunya. Hendra. Nipah. Pandemic influenza. Other, novel influenzas. And of course, the Ebola virus disease outbreak that is still ongoing in Guinea and Liberia (though cases have finally slowed to a mere trickle).

And we’re still unprepared for them when they become explosive, as Ebola did in 2014. Analyses have showed that the delayed response to that outbreak cost lives. And that’s for a virus that is not particularly easy to transmit, as it’s only spread late in the illness via direct contact with infected bodily fluids. If that had been another virus that was airborne instead of bloodborne, the world could have been in a much worse situation. Now imagine that it was the Solanum virus of World War Z (the book version), slowly incubating in infected individuals as they move all over the globe. Definitely unprepared.

Furthermore, even with our handful of cases in the U.S., we saw that the hype and misinformation about Ebola was out of control. We saw this with H1N1 in 2009 as well, and H5N1 before that. We’re still, as a whole, pretty bad at communicating about infectious disease threats–striking that correct balance of assurance that we know what we’re doing, but acknowledging the gaps in our data and how we’re working to address those. It’s not an easy thing to do, but we need to continue improving. Because again, that’s how it always starts in zombie movies, right?


Ebola and zombies also lead to ethical dilemmas. As I noted in the paper, for a zombie outbreak, there would remain the question of quarantine (for those exposed/bitten but not yet sick), and isolation (for those who are ill)–how would those be handled? What if quarantining the healthy-but-exposed led to essentially a death sentence, as the bitten would inevitably “turn”, and possibly start chowing on the still-living who were quarantined with them? Again, ridiculous on its face, but it has parallels in real-life outbreaks and the legality and ethical quandaries of when to use such measures (and, of course, used with the assumption that they would be effective–which doesn’t always hold). There are accusations that these were violated last year, when individuals coming back from working the Ebola outbreak were quarantined–lacking in scientific justification for sure, and potentially illegal as well.

Using zombies in lieu of real diseases gives researchers, public health professionals, policy makers, and laypeople the ability to discuss these heavy issues without getting bogged down in one specific outbreak or pathogen, because many of the problems we’d face during the zombie apocalypse are similar to those that come up in any serious epidemic: coordination. Funding. Communication. Training. Access to treatment or prevention. Though I didn’t discuss it in this particular article, proper personal protective equipment (PPE) is another issue–both access to it (lacking in developing countries), and being sure to choose the right gear for the outbreak (“overprotection” is not always better). Further, it encourages individuals to put together their own zombie (disaster) preparedness plan, which is how the CDC has used the zombie phenomenon.

In short, it’s way more fun for the average person to shoot the shit about zombies than to have a more serious discussion about influenza, or Ebola, or whatever the infectious disease du jour may be–and maybe even learn a bit of science and policy along the way.


The microbiology of zombies, part V: beware the bite?

Now that seemingly the flu outbreak storyline has been wrapped up on The Walking Dead (unsurprisingly, but disappointingly, with their ineffective treatments proving to be miracle cures), there’s still one more zombie microbiology topic I’d like to cover: what’s up with the bite, and is it the cause of death? I said previously:

“We know the pathogen can certainly be spread by bites and then cause zombification that way…”

but one commenter disagreed, noting:

“I don’t think we have evidence for that from the show. I think it clearer that zombie bites cause death, and there doesn’t seem to be evidence that the agent that causes death also causes zombieism (or vice versa). In Walking dead, any death is a sufficient condition for becoming a zombie. I would guess that zombies cause death because of a massive polymicrobial infection/sepsis.”

So, could death be due to massive sepsis (an overwhelming immune response to infection, which can lead to organ failure and death) via the bite, rather than the introduction of a specific zombie pathogen? It’s certainly not the first time I’ve seen that argument. Even the Zombie Research Society has put that forth as a hypothesis (and Matt Mogk has written of it in his book as well). However, I don’t buy it for a few reasons.

First and foremost, human bites simply aren’t that deadly. Even in a study of patients presenting to emergency rooms (which are probably the most serious of bites), none were found to have sepsis. Well, you might say, maybe more would have had this if antibiotics weren’t available, which would be the case with TWD (well, except now they have them, but I digress…) A Medscape article addresses this, noting that prior to the antibiotic era, up to 20% of bites caused amputation of a finger–but still, a local nasty infection, not necessarily sepsis. Even in a 1936 NEJM paper studying bites, only 2 deaths are noted, and both are in “delayed cases”–individuals who waited 5 days post-bite to present to the hospital. In these cases, the cause of death is indeed listed as “extensive sepsis.”

However, it should be noted that hand bites in particular—the subjects of those papers and articles above– seem to be rather nasty. Per Medscape again, “… most human bite injuries occur on the hands, and hand wounds from any cause have higher infection rates than do similar wounds in other anatomic locations.” So, these papers focus on the worst types of bites (hand injuries) at the most severe locations (presenting to emergency rooms), and thus should be considered likely a worst-case scenario for our potential infectees: that, even if bitten, a minority of them would have serious complications, and a minority of those might perish of sepsis. This doesn’t match up with what we see in the show.

You might argue that the process of zombification would modify/increase the nasty bugs living in the mouth. I agree–rotting in this manner certainly could alter the presence and types of organisms that would be present in the mouth, and therefore possibly make them more deadly and more likely to result in a sepsis death of the bitten. However, even accounting for rapid reproduction rates for microbes (mostly bacterial when you’re talking about sepsis and oral germs), this doesn’t seem to be a satisfactory answer, as one can quickly die and be reanimated and immediately have the potential for a deadly bite. It could also be argued then that therefore *everyone*, living or dead, would also possess this quality in that case–it shouldn’t matter if the bite is from a zombie or from a living person; the result should be the same (sepsis and zombification).

Further, in the human bite literature, there are two types of bites typically described: occlusive bites and clenched-fist injuries. The former is probably what you think of when you think zombie bites: mouth open, teeth coming together on the skin, chomp, chomp, chomp. Clenched-fist injuries are what happens when someone strikes another person’s teeth with, as the name suggests, their clenched fist, often scraping the knuckles: basically, a punch that strikes the teeth/mouth. While on the Walking Dead the former universally mean death (except in the case of really quick amputation of the bitten part, like we saw with Hershel’s leg), we’ve seen many examples of the latter—how many fistfights has Rick alone gotten into now? Not to mention, scenes like this:

 So if one is going to support the “polymicrobial infection as a result of bites” scenario for zombification, the issues of living biters need to be explained away as well.

Others have argued along similar lines regarding bites and sepsis, suggesting that the zombie bite is analogous to what happens to the prey of the Komodo dragon:

“Animals that escape the jaws of a Komodo will only feel lucky briefly. Dragon saliva teems with over 50 strains of bacteria, and within 24 hours, the stricken creature usually dies of blood poisoning. Dragons calmly follow an escapee for miles as the bacteria takes effect, using their keen sense of smell to hone in on the corpse.”

The problem with that analogy is that it’s based on a myth. That’s not what really happens: the dragon actually has venom, as I noted way back in 2005 (and Ed Yong updated recently, both based on the work of Bryan Greig Fry). It’s not their bacteria that kill their prey, but their venom. Do zombies suddenly become venomous? Doubtful. So, another idea shot down.

To me, the most convincing scenario, and the one that seems to jibe with both the idea that everyone is infected and with the little we know about the epidemiology of the outbreak, is that the immune system keeps the “zombie virus” under control while one is still alive and healthy. When one dies, the virus is allowed to replicate unchecked, resulting in both zombification/reanimation as the infection proceeds unabated throughout the body. The virus would also replicate (probably within the salivary glands) in order to enable transmission to the next bite victim. A zombie bite then introduces a large amount of this virus right into the bloodstream of the target, which overwhelms the body’s defenses and is responsible for both death and subsequent zombification—like rabies virus on steroids—and the cycle perpetuates itself.

Bottom line is that with the sepsis model, you have to explain more anomalies than with a virus-death model. You’d need to postulate immediate changes in the oral microbiome that aren’t readily accounted-for, but would be responsible for the 100% fatality rates upon receiving a bite (but ONLY a zombie bite, and not a live-human bite), while with the novel zombie virus model you get a bit more carte blanche to account for the transmission and certain death. That seems a much better explanation to me.

 Works Cited:

Welch CE. Human bite infections of the hand. NEJM, 215:901. 1936.

Talan DE et al. Clinical Presentation and Bacteriological Analysis of Infected Human Bites in Patients Presenting to Emergency Departments. CID, 37:1481. 2003.

See also:

Part I: the microbiology of zombies

Part II: ineffective treatments and how not to survive the apocalypse

Part III: “We’re all infected”

Part IV: hidden infections

The microbiology of zombies, part IV: hidden infections

(As previously, spoilers abound)

So on this week’s Walking Dead soap opera, we find that Daryl/Michonne’s group is still out and about searching for medical supplies. Back at the prison, the food situation is dire (apparently all the food stores were in the cell block where the infection broke out), so Rick and Carol head out to look for both medicines and food from the local ‘burbs. During their outing, discussion ensues of Carol’s attempt to stop the prison’s apparent influenza outbreak by killing two people who, at that point, were the only ones showing symptoms of disease. Rick decides he can’t trust her, and ends up banishing her from the group.

Carol said multiple times that she was trying to do the right thing, to protect the rest of the group from those who were sick and was only trying to end the outbreak. However, here’s where some knowledge of infectious disease would have helped her. Every disease has an incubation period: the time when the microbe is multiplying in your body, but you’re not showing any physical disease symptoms yet. This can be short–as little as perhaps a few hours for something like Salmonella food poisoning. It can be extremely extended, as I mentioned with rabies virus in my previous post, where the incubation period can be months to years. With influenza, the typical incubation period is 2 days, but it can be as short as 1 or as long as 4-5. The kicker is that a person who’s incubating flu can still spread it even before they show symptoms of the illness. So just because Karen and David were the only ones actively coughing and looking miserable, Carol was mistaken in her assumption that they were the only ones infected, and that she could stop the outbreak by snuffing them.

This is the difference between two similar concepts, quarantine and isolation. People who have been *exposed* to an infectious agent, but are not yet showing any signs of illness, can be quarantined to keep them away from others due to their *potential* to spread a disease. Those who are already showing signs and symptoms are placed into *isolation* to keep them from spreading it–they’re a known quantity. The prison group has used primarily isolation to keep the infection from spreading: they’re putting the ill in the Death Row cell blocks as an isolation area, and those who are well can roam around as they choose. (Maggie, for instance, hasn’t been sent to quarantine even though she clearly was exposed to the illness by being in such close contact with Glenn).

However, one thing that the group hasn’t yet determined (probably because no one has recovered as of yet) is how long they’re going to keep anyone who gets better in the isolation area. Though adults usually stop releasing influenza virus even before their symptoms are completely gone, kids can shed the virus for a long time: up to two weeks after their symptoms started according to one study (and others have found similar results). So while right now they have the healthy young children segregated from everyone else for their own protection, in theory, if Lizzie (the flu-infected child currently in held in isolation) gets well and is released back to the healthy kid’s room, she could simply re-start the outbreak there, among the most susceptible. 

This is why disease eradication is so difficult, and why it’s been accomplished for so few pathogens to date: many pathogens can spread on the sly, even when people don’t know they’re sick. For influenza, even if it’s knocked down in this group (and of course, it soon will be one way or another–at some point, the susceptible hosts in the prison will be exhausted, either by infection & recovery or by death), there is always another reservoir of disease out there. It may be other humans. Darryl/Michonne’s group finally made it to the veterinary school mentioned two episodes ago, and the zombies they ended up fighting there had clinical signs that looked an awful lot like the survivors had seen at the prison: blood that had come from the eyes and nose. Had flu been circulating there as well? It’s a vet school, pigs could certainly be housed (there were a number of animal cages, and could easily be an outdoor space for livestock somewhere). So pigs could be serving as a reservoir. Flu can also come from a number of other animals–most notably, birds, who don’t even have to appear sick to transmit the infection to people.

Infections can be sneaky and unseen, as this group should well know.

See also:

Part I: the microbiology of zombies

Part II: ineffective treatments and how not to survive the apocalypse

Part III: “We’re all infected”

The microbiology of zombies, part II: ineffective treatments and how not to survive the apocalypse

(Spoilers. And things.)

After the start of season 4 of the Walking Dead and the introduction of a new nemesis: a fast-spreading, deadly infectious disease that seems to be a strain of influenza, I was looking forward to the plot arc of this season.

And then episode 3, “Isolation”, happened. From an infectious disease standpoint, I say, bah.

At the end of the previous episode, “Infected”, the group had decided to lock up anyone who was showing signs of the infectious disease within the death row cellblock, so that they would not further spread the disease, and to put the children and elderly (as the most vulnerable population) in another area to keep them safe from the infection. Quickly it was seen that this wasn’t working well, as people were becoming sick all over and more and more were moving into the isolation cellblock.

So, a council meeting was called of the leaders of the group. One of the decisions which was made, on the advice of Hershel the veterinarian, was to try to scavenge supplies from a college of veterinary medicine approximately 50 miles away from their location at the prison. What supplies?


For the micro people reading, you’ll see why my rage started boiling a bit at this point. Hershel was the one who’d suggested this was an influenza outbreak (and therefore, caused by a virus) in the prior episode. He is familiar with the disease (and there is another physician, Dr. Subramanian, who has been treating the ill and has seen the rapid course of the disease–of course, he is now sick himself). It is true that influenza can be complicated by a secondary bacterial infection: that those sick with the flu could develop pneumonia due to Staphylococcus aureus or other bacteria, and that these bacterial infections would respond to antibiotic treatment. But, when the course of disease is as rapid as it appears to be during this outbreak, it’s more likely that people are dying from primary influenza infections, which are most certainly NOT treatable with antibiotics. There are antiviral drugs that can treat influenza infections if given early in the disease course (such as oseltamivir or zanamivir ), but I think the odds of those being stocked at a veterinary school would be pretty slim.

So, rather than at least try for some kind of medically plausible scenario (is that really too much to ask?), Daryl, Michonne, Tyreese and Bob the medic take off in search of completely ineffective antibiotics,and run into an enormous zombie horde on the way. Hershel, in the interim, leaves the relative safety of the prison (he was ensconced with the children as a “high risk” individual) and wanders out into the woods to pick berries and leaves to brew elderberry tea. A folk remedy, there are a few peer-reviewed publications which suggest that elderberries or elder flower might have some properties that do work to treat influenza, so at least here Hershel is, well, sucking somewhat less here when it comes to proposing medical interventions to help those suffering than he did with his terrible antibiotics idea.

Hershel does end up with his tea, taking it into the isolation cell block and distributing it to the infected. This includes Dr. Subramanian, who repays the favor by coughing bloody sputum all over Hershel’s face. (Seriously, he doesn’t even know how to cough into his elbow? Even the little girl talking to Carol did that correctly).

From the previews of next week’s episode, “Indifference”, it appears there will be more searches for drugs, while presumably the horde advances toward the prison. I anticipate a miracle cure of some kind for Glenn at the least, but remain annoyed that the writers are touting antibiotics for a viral infection when flu season is upon us.

See also:

Part I: the microbiology of zombies

Part III: “We’re all infected”

Part IV: hidden infections

Interview with “Warm Bodies” author Isaac Marion

And now for something a bit different. I’ve mentioned before that I’m a big fan of zombies. So, I was intrigued when I started seeing press for Warm Bodies, a book by Isaac Marion about a zombie who is, well, not your typical zombie. Recently released as a feature film, I read the book a few weeks ago, and last weekend took my 13-year-old daughter to see the movie. I enjoyed both (as did my daughter), and asked Isaac if he’d be willing to answer a few questions for the blog. His interview is below (a few spoilers, take note):

Tara: Your take on zombies is a bit different than most stories. Obviously there’s the central idea that they can be “cured”–and they also talk and have friends. I saw in a previous interview that you said you’d kind of “stumbled” into the zombie genre and were not always a zombie geek. Can you describe your experience emerging as a bona fide zombie author, and what has the reaction to the book/movie been from the hard-core zombie community?

Isaac: The reaction has been pretty much split between two camps. Camp 1 is people who understand that a zombie is a fictional creature that has been portrayed differently, with different origins and different behavior, in pretty much every iteration and remains open to interpretation depending on the goals of the story in which it appears. That camp thinks its a great new idea and welcomes the unexpected shift in perspective that explores a lot of the unaddressed questions in zombie lore, while using the mythology to explore other, more human themes. Camp 2 is people who I don’t understand at all, who seem to think that zombies are real creatures that have been studied and defined by science, and that there are immutable “rules” to how they should function in fiction. These people tend to ignore the fact that every major work in the canon of zombie mythology has redefined what zombies are. First, they were regular people brainwashed by Haitian voodoo powder. (White Zombie.) Then they were corpses reanimated by mysterious cosmic radiation. (Night of the Living Dead.) Then they were regular people driven insane by a virus. (28 Days Later and onward.) In the midst of all this, we saw zombies with lingering consciousness who responded to music and speech (“Bub” in Day of the Dead) self-aware zombies capable of independent thought and even leadership (Land of the Dead) and yes, zombies who fall in love. (Fido.) I don’t really know what it means to be part of a “zombie community” but I’m certainly well familiar with the “genre” if all stories about a certain creature can be lumped into one genre. (Why is “Dragon” not a genre? Why is there no “Robot genre”? I don’t even think “Vampire” is considered its own genre.) My roots run pretty deep into geekdom, so it’s not like I just decided “I think I’ll write a zombie novel” and then had to research what the fuss was all about.

Tara: Each zombie story also seems to come up with their own terminology for zombies: “walkers,” “skels,” “Z’s,” “stragglers,” “biters,” etc. Yours are “corpses”, “the Dead,” and “Boneys,” though you do occasionally break the unwritten rule and refer to them as zombies. Was it important to you to try to differentiate your Dead from those that had come before in other movies/books?

Isaac: I think Warm Bodies is kind of a mashup of all the zombie fiction that came before it. I wasn’t trying to create a new “version” of zombies to add to the canon, I was trying to use all the tropes of that canon for satirical and metaphorical purposes. So I just combined everything–R doesn’t know where zombies came from, but he references every well known origin story in his musings. One of the unusual things about Warm Bodies’ universe is that it’s actually our universe. These people knew about zombies in fiction before they became reality. They’ve seen the George Romero films. So when zombies first started to appear, it wasn’t just “Oh my God there are corpses coming to life!” it was, “Oh my God, our collective cultural nightmares are becoming reality!” This is only briefly referenced in the movie (Julie holds up a copy of the 1979 film “Zombie” next to R’s face at one point) but it’s a little more explicit in the book and will be explored further in the sequel.

Tara: Zombie stories run the spectrum from trying to create very scientifically legitimate zombies (“Neuropathology of Zombies,“The Zombie Autopsies”–even “Zombieland” suggested the outbreak had resulted from a mutated “mad cow” infection) to not even trying to justify them scientifically. In the book, R can’t remember anything about how the world ended or the zombie plague may have begun, while Julie muses that it started when humans “buried themselves under greed and hate” until they hit the bottom of the universe, and then kept on digging–an idea more along the lines of a curse rather than an infection. And of course, The Dead eat the brains of the living and by doing so, gain their memories–so yours swings pretty far to the “not even trying” end of the spectrum. Were you worried about how that would be received when so many recent zombie stories have tried to be a bit more rooted in reality?

Isaac: The stories that root it in reality do so because they aren’t really about the zombies themselves, they aren’t using zombies for any thematic purpose beyond maybe some light social commentary, they’re mostly just props to menace the characters and create action. Obviously, with a zombie narrator, Warm Bodies is much more about the Dead themselves, and what it means to be in that state vs. fully alive. I didn’t use any science because this is a metaphorical story. In the sequel I’m writing now, it will go deeper into the actual metaphysical causes of the plague and the way human consciousness influences reality, but it definitely won’t reveal some random virus to explain everything. Most zombie stories use something like that because it’s quick and easily understood and clears the field for all the action and visceral thrills. That’s not really what these books are about.

Tara: When I first read the description of “Warm Bodies,” I admittedly cringed a bit. Like many others, I was a bit apprehensive that it was going to be a “Twilight” for zombies. Thankfully, R wasn’t sparkly like Edward and Julie wasn’t a pathetic wimp like Bella, and I was pleasantly surprised with how much I liked the book and the movie. Like much great zombie fiction, your book is entertaining but also has a bigger message about the state of society–very Romero-esque, even if your zombies are much different than his. How did the novel evolve from your initial short story, just musing about what a zombie might think about, to the richer allegory of the finished product?

Isaac: It had a lot to do with the state of my own life at the time I was inventing this story. I had moved from my small hometown to Seattle a couple years before and had left behind my conservative religious upbringing in the process. It was a weird moment in life, where I was trying to understand who I was and what my purpose was outside of this very small-minded, limiting, ultimately pessimistic worldview that I had grown up with. And beyond that, I was getting older, feeling the loss of energy and passion that comes with age and experience and trying to find a way to fight it off. So I started to notice a lot of parallels between my life and this unhappy corpse living in the wreckage of civilization, and my transformation started to connect with his. The story kind of just exploded out of me in a short period. I think it was a therapeutic experience for me as a person. Writing it helped me figure out some of my own struggles.

Tara: Still, it is a romance, complete with “R and Julie” and even a balcony scene. Like the play, R and Julie brought about change and a healing in their respective populations, even if that was not their intent. Why did you decide to incorporate that story and those references into your novel?

Isaac: It kind of just happened by accident, actually. I was fairly deep into plotting it when I noticed the ways my story had assembled itself around that classical arc, and I decided to run with it. To me, the Shakespeare allusions are just another layer, not really the central theme of the story, although people are quick to call it “Romeo and Juliet with Zombies.”

Tara: There seems to be a rash of first-person zombie stories lately–Hugh Howey’s “I, Zombie”, “Brains” by Robin Becker, or “Zombie, Ohio” by Scott Kenemore, in addition to “Warm Bodies.” Do you see this as a new trend–a humanization of the zombie?

Isaac: I’m not familiar with any of those. I would imagine people probably have similar thoughts to the one that first inspired my short story: “Why hasn’t this been done yet?” Villains are almost always more interesting than heroes. It’s always fascinating to get inside the mind of the bad guy and try to understand them. For thousands of years we’ve been watching the pure white knight slay the monster, and it’s getting old. People are starting to understand that morality and motives are complex and we want to know more about what goes on in the darker half that’s been hidden away from us for most of the history of fiction. I think as society becomes more and more comfortable with moral ambiguity, these kinds of perspective swaps will become more and more common.

Tara: Can you tell readers a bit about “The New Hunger” and your anticipated sequel to “Warm Bodies”? Any other writing projects you’re kicking around?

Isaac: “The New Hunger” is a novella that takes place seven years before Warm Bodies, involving a formative early encounter between Julie, Nora, and a newly undead R. It illuminates their histories and expands the scope of the world a bit, while foreshadowing a lot of what’s going to happen in the sequel. The sequel is going to be a lot bigger and more complex than Warm Bodies, less about zombies than death itself and the forces, human and inhuman, that make our world a dark place when it doesn’t have to be. It will explore some more metaphysical, even cosmic themes, and veer more toward modern fantasy than zombie horror. I’m pretty excited about it.

Many thanks to Isaac for participating! You can find out more about him via his website, or follow him on Twitter.

Using zombies to teach science

With my colleague Greg Tinkler, I spent an afternoon last week at a local public library talking to kids about zombies:

The Zombie Apocalypse is coming. Will you be ready? University of Iowa epidemiologist Dr. Tara Smith will talk about how a zombie virus might spread and how you can prepare. Get a list of emergency supplies to go home and build your own zombie kit, just in case. Find out what to do when the zombies come from neuroscientist Dr. Greg Tinkler. As a last resort, if you can’t beat them, join them. Disguise yourself as a zombie and chow down on brrraaaaiiins, then go home and freak out your parents.

Why zombies? Obviously they’re a hot topic right now, particularly with the ascendance of The Walking Dead. They’re all over ComicCon. There are many different versions so the “rules” regarding zombies are flexible, and they can be used to teach all different kinds of scientific concepts–and more importantly, to teach kids how to *think* about translating some of this knowledge into practice (avoiding a zombie pandemic, surviving one, etc.) We ended up with about 30 people there: about 25 kids (using the term loosely, they ranged in age from maybe age 10 to 18 or so) and a smattering of adults. I covered the basics of disease transmission, then discussed how it applied to a potential “zombie germ,” while Greg explained how understanding the neurobiology of zombies can aid in fleeing from or killing them. The kids were involved, asked great questions, and even taught both of us a thing or two (and gave us additional zombie book recommendations!)

For infectious diseases, there are all kinds of literature-backed scenarios that can get kids discussing germs and epidemiology. People can die and reanimate as zombies, or they can just turn into infected “rage monsters” who try to eat you without actually dying first. They can have an extensive incubation period, or they can zombify almost immediately. Each situation calls for different types of responses–while the “living” zombies may be able to be killed in a number of different ways, for example, reanimated zombies typically can only be stopped by destroying the brains. Discussing these situations allows the kids to use critical thinking skills, to plan attacks and think through choice of weapons, escape routes and vehicles, and consider what they might need in a survival kit.

Likewise, zombie microbes can be spread through biting, through blood, through the air, by fomites or water, even by mosquitoes in some books. Agents can be viral, bacterial, fungal, prions or parasitic insect larvae (or combinations of those). Mulling on these different types of transmission issues and asking simple questions:

“How would you protect yourself if infection was spread through the air versus only spread by biting?”

“How well would isolation of infected people work if the incubation period is very long versus very short?”

“Why might you want to thoroughly wash your zombie-killing arrows before using them to kill squirrels, which you will then eat?” (ahem, Daryl)

can open up avenues of discussion into scientific issues that the kids don’t even realize they’re talking about (pandemic preparedness, for one). And the great thing is that these kids are *already experts* on the subject matter. They don’t have to learn about the epidemiology of a particular microbe to understand disease transmission and prevention, because they already know more than most of the adults do on the epidemiology of zombie diseases–the key is to get them to use that knowledge and broaden their thinking into various “what if” situations that they’re able to talk out and put pieces together.

It can be scary going to talk to kids. Since this was a new program, we didn’t know if anyone would even show up, or how it would go over. Greg brought a watermelon for some weapons demonstrations (household tools only–a screwdriver, hammer and a crowbar, no guns or Samurai swords) which was a big hit. Still, I realize many scientists are more comfortable talking with their peers than with 13-year-olds. Talking about something a bit ridiculous, like an impending zombie apocalypse, can lessen anxiety because it takes quite a lot of effort to be boring with that type of subject matter; it’s entertaining; and kids will listen. And after all, what you don’t know, might eat you.

Infectious disease epidemiology and zombies

Have two awesome announcements that I’ve been waiting to share. One will still have to wait a few more days as we’re finalizing some details, I can now let you know that I just started a new position as an Advisory Board member of the Zombie Research Society. It’s a pretty cool group, including THE George Romero (Zombie Godfather); Daniel Drezner, author of Theories of International Politics and Zombies, and Steven Schlozman, author of The Zombie Autopsies. Plus a bunch of other white guys.

So, why do something like this? Zombies obviously are huge in pop culture, and typically “zombieism” is caused by some kind of transmissible infectious agent. As such, it’s a good way to talk about infectious diseases in a more lighthearted and fun manner. The CDC already took advantage of this with their popular “Preparedness 101: Zombie Apocalypse” page, while Robert Smith? demonstrated the utility of using a zombie outbreak to model infectious diseases. I think there’s more to be explored and am looking forward to the journey.