This post originally appeared on Randi.org
Bent on gorging ourselves on bleak and bloody visions of our own destruction, pop culture as of late has been zombified. These shambling simulacrums of our own mortality have broken through the boarded-up doors of our hearts and gnawed lovingly on our brains. This resurgence of a classic horror genre is obviously a welcome one, as exemplified by the success of shows like The Walking Dead, and the fact that the CDC used a zombie apocalypse scenario as a PSA for disaster preparedness.
Zombie doodle courtesy of Sara E. Mayhew
Seemingly everyone has had their love of zombies reanimated: mathematicians published a paper modeling a zombie outbreak to examine pandemics, researchers and students at the Large Hadron Collider made a full-length zombie movie in between particle smashings, and popular video games from Red Dead Redemption to Call of Duty all have joined the brain-matter-hungry mob.
It’s a good thing, if we can believe any zombie-themed media, zombies don’t actually exist. Nearly every outcome is Mad-Max or Fallout. It’s undoubtedly fun, and rather macabre, to speculate how a virus-spreading and ever-growing gang of gangrenous flesh gorgers would ruin our world (or at least a city or three). The zombie apocalypse is then a tried and true thought experiment combining our fascination with death and gore with epidemiology and disease.
But a zombie-laden thought experiment needs a counterpoint. Allow me: a zombie apocalypse would never happen.
All the Worlds a Stage…For a Zombie Apocalypse
First things first. Any discussion of a zombie apocalypse (from now on ZA) needs to get its canon straight. Are we talking about the Dawn of the Dead zombies, slow-moving and mindless undead, or are we talking about 28 Days Later zombies, objectively terrifying with ferocious speed and viral transmission?
I suppose if we take the “average” zombie portrayal, we are talking about zombies from shows like The Walking Dead: mindless, slow-moving, rotting human corpses, both hungry for human flesh and able to “turn” individuals unfortunate enough to be bitten.
We also have to imagine a stage—how the ZA got started. Was it a virus, an unholy rising, a parasitic takeover akin to the Ophiocordyceps parasitic fungus that forces ants to distribute spores before killing them? Again, the most popular scenario seems to be a virus spread by an unlucky chomp from a bloodthirsty ghoul.
Finally, let’s also suppose, as in The Walking Dead, that there is a national (or even global) simultaneous zombie outbreak. Here is where, if we aren’t to fully suspend our powers of critical thought, a ZA’s plausibility drops dramatically, like a zombie run through its rotting brain. We give ourselves far too little credit. Humans are amazingly talented killers.
Winning World War Z
Zombies would not be the terrors we make them out to be (if we must argue realistically about something that isn’t real). They lack the two things that make humans dangerous in the first place: having a mind and being able to run. Speed and endurance running, combined with the ability to plan, coordinate, and to use tools/weapons, makes for a dangerous animal. A zombie is like a toothless shark that can no longer gracefully cruise the shoals.
But what about the numbers? The inherent danger of a ZA isn’t the risk posed by one hungry corpse, but by an onslaught of them, perhaps shoving themselves grotesquely through your shattered first floor windows and splintered doors. Here is where zombie narratives sell humanity short.
Humans are skilled murderers, time and again proven excellent at killing, especially each other. Consider the history of genocide; how good we are at killing other humans who can think and plan and run away, in mass amounts. Why would it be harder to kill non-thinking, slow moving humans if we are already so good at killing ourselves?
Try a simple thought experiment, channeling the terror of a house surrounded. Say you have 25 individuals who are set on eating your face. Would you prefer them to be live humans or undead zombies? Most people I believe would choose the zombies. Even the dumbest humans are more dangerous than a pack of mindless meat sacks. Even unarmed people are scary.
But what about the global outbreak? At last estimate, human existence is at least partially responsible (through deforestation, human expansion, etc.) for the extinction of at least 100 species of other organisms every 24 hours. With no goal, no survival instinct rallying humanity to push back from the brink, we casually obliterate entire genetic lineages. If we had the goal of wiping out an outbreak of slow moving packs of rotten meat, we would be violently capable.
And speaking to the idea of a contagious virus, if the CDC can eradiate malaria from the US, we could handle a zombie outbreak.
But what if the military or police force falls? You’ll forgive me for being a bit evasive on an answer to an imaginary disaster, but the military wouldn’t succumb to a mindless mob. An overrun defense force is merely a plot device. In the ZA narratives that use it, they take away the military because it makes for a boring story if they didn’t.
Why a military force would fall, especially as terrifying and well-equipped as America’s, has never been explained. Jets and bombs and drones and tanks and Apache helicopters and rocket launchers and Gatling guns that can fire 3,000 rounds a minute. Does any of this arsenal, feared (and lamented) by the rest of the developed world, suggest a simultaneous and catastrophic demise brought on by senseless automatons?
But what about the environment? Admittedly, being trapped in a city overrun by the undead isn’t ideal, but it isn’t a death sentence, nor is it representative of most of the country (or the world). America itself is so big, that even if 90% of the US population were zombified, a zombie encounter would be few and far-between (if evenly distributed). The country of wide, open spaces means that there is almost always a place you can run.
And where do you run? Anywhere cold. One or two winters in the boreal forests of Canada, for example, with its freezing temperatures and healthy bear/wolf/cougar population, would make short work of slow, rotting, meat.
It only gets more implausible from there.
The Semantics of Eating Brains
Mathematical models have fun showing how a zombie apocalypse could spread across the globe but leave out almost all of the aspects of a plausible human resistance to it. In short, the zombie apocalypse only comes about because of conveniently placed lynchpins of annihilation. Without a mysteriously bested military, or a vanishing of all the guns and ammunition that litter the United States (a gun for every man, woman, and child, on average), the thinking ape won’t be overcome by the non-thinking, dead version of one.
But while we are speculating, what would be the best zombie weapon? A gun of course. Barring the unexplained plot point of, “We have to save ammo because there isn’t any around,” just hole up at a Wal-Mart. We sadly know how abundant guns are, and just how much ammunition is available.
Many of these points depend on your own interpretation of the canon and the numerous variables involved. I am not saying that every permutation of the now ubiquitous zombie story will end with thawing, rotting meat being exterminated by hungry bears. However, I think it’s useful, if we are to discuss this, to think of real-world implications and at least consider that a future ridden with zombies doesn’t have to end up like I Am Legend, The Walking Dead, or Zombie Land. We could actually win this thing. But I’m still stocking up on machetes just in case those 28 Days Later zombies show up.
Feel free to argue with me in comments, but keep in mind that’s already more than a zombie could do.
This post comes in large part from a discussion I had with manga artist and TED fellow Sara E. Mayhew, who spoke at last summer’s Amaz!ng Meeting.
Further Reading:
How to Control an Army of Zombies—Carl Zimmer
The Walking Dead—Kills, Deaths, and Weapons [Infographic]
Dumb Ways to Die—The Walking Dead Style
Science-Based Life 
Hi Kyle,
I’ve read your post, as I do regularly, and found it very entertaining and instructive as always. I think I was never a big zombie fan, but the Walking Dead series may have changed that a bit. I watch the series religiously (even if it is not that easy here in Portugal) and I think I’ve re-discovered the zombie genera. I’ve seen the remake of Dawn of the Dead by Zack Snyder and enjoyed it tremendously. Having said this, it would have been interesting to read you discussing further arguments against a zombie outbreak. I have a biology background and what is compeling to me is the notion that a deadly virus could in theory go global and have desastrous consequences. I’m not saying that a zombie outbreack could happen, but if you combine a higly contagious (fast mode of transmission – air-born, for example) and deadly virus with apparently unafected and mobile carriers, who can spread the virous at an early stage (as it is the case in the Walking Dead), you have recipy for disaster. In reality, there are no known viruses that combine those features so well. Think of HIV to have an idea of how much harm apparently unaffected carriers can do (in this case, the mode of transmission is among the slowest). And think of Ebola to have an idea how close to an undead you can get, but that leaves you and other infected close to you imobile and very unlikely to spread the virus further (everyone is killed before transmission can be carried further). It is this unlikely combination of virus features that is most compelling to me. Probably the closest we got to that was the influenza epidemic that spread at the end of WWI (think of all those millions that died turned into zombies as well as the millions more who were affected but did not die). On most respects, I agree with you, as is it hard to explain how the military would fall. On the other hand, if you think outside the US I cannot imagine where people would get the guns and ammo to take down the zombies (and ammo does eventually run out). Of course, I’m not arguing for the possibility of a zombie apocalypse, but I think you can carry your arguments further. For example, as a biologist and anthropologist (with several years of forensic experience), what strikes me as most unplausible is the fact that (in the case of the Walking Dead in particular), 1) a corpse, i.e. a dead body, can actually move even if mindless. If you’re dead, all the ATP (adenosine tri phosphate – where cell energy from) in your cells has broken down and your muscles simply don’t have the energy to contract and, hence, you can’t move or walk. So we would have to imagine some sort of energy being delivered directly to these zombies’ cells (eating humans doesn’t work, because if you’re dead you can’t digest). Even if ATP does not break down after death, it runs out pretty fast, so zombies would only have energy only for a few days. The other issue is that 2) zombies also seem to have the capacity of stop decomposition at some point. If you’re dead, your body will break down pretty quickly and I’ll be turned into bones sooner or later. The fact that zombies can survive in a suspended decomposiiton state, also strikes me as a shortcoming of a zombie outbreak that lasts for months or years. In the end, as a biologist/anthropologist what strikes me as most unplausible and unexplained in a zombie outbreak is how they get their energy to wander around, and how they can alt decomposition. Other than that, despite any zombie unplausibility, I’m just glad we can have fun killing them on L4D, Dead Island, Dead Rising, Call of Duty, Dead Space, Half-Life or the recent addicting great Deadlight. Thank you for your post and for having me talk about zombies;)
Best
Hugo
At lest I can explain the at decomposition. The body decomposition requires a los of microorganisms to digest the rotten body but the virus can become letal to all of them, basically Z virus will cure you of all diseases other than Z. That will reduce the changes of body decomposition pretty much like the mummification works, it will eventually decompose but due to physical effects, not biological.
but this is not possible. You cannot have a virus that is lethal to ALL microorganisms, the same virus that is capable of controlling human minds and magically raise people from the dead.
Its not science anymore, its magic.
thats actually how i reassured a little kid once who was scared of zombies i pointed out that since zombies were dead they couldn’t digest food and that meant they would stop moving after a few days
Fun stuff! The only thing scarier than the ZA is when joking about it with friends over drinks and then you realize that someone at the table is taking it MUCH too seriously……
Heh, you think you know someone until they drunkenly divulge their underground bunker full of guns.
I know, right? I mean, where’s the US army? But of course we have to suspend our disbelief, and just enjoy the show.
Oh, if aliens of the Independence Day kind suddenly ” invade” the planet, we’re scr*wed. (6.6)
Cheers !
(in regards to the Independence Day alien invasion)
Not necessarily. If the ID version aliens did wage war on humanity, it’d be a more or less even fight. Since the aliens had a similar physical make-up, and could be killed just as easily with a fired bullet, land-based war would be in humanity’s favor. Air-based battles, as depicted in Independence Day, would be a little trickier, however. Since the aliens used shields which repelled the weapons thrown at them, we’d have to be more creative. Consider the usage of anti-matter weaponry. As far as I’m aware, there isn’t any form of matter that won’t be annihilated when coming into contact with its counterpart, anti-matter. If, say, an anti-matter missile (if that is even possible) was fired at an alien ship with shielding, it wouldn’t stand a chance.
But anyways, as you said, we suspend our disbelief to enjoy the media.
Great read, Kyle! Very interesting.
Antimatter missiles aren’t possible. Antimatter detonates on contact with any matter. So I ask what could possibly contain antimatter until point of impact?
Any species capable of interstellar flight would be able to: 1)survive for long periods in space, 2)be capable of destroying all earth satellites, 3)be capable of raining death onto the planet for decades until a nuclear winter ensues and crops fail, civilization fails and industrial production stops. You could cause the downfall of humanity from orbit over a 25 year time period and land when resistance would be…futile.
I’m a big horror fan myself, and the thing I found most ridiculous about zombies taking over the World, the traditional slow ones, is just that. They’d be so easy to manage. Your average day wouldn’t change much, you’d just have to keep some sort of Zombie Dispatching Device in your car like you would an ice-scraper or car-jack.
Mira Grant examines this idea in her ‘Newsflesh’ trilogy. She reworks the ZA into something that’s plausible from a epidemiological standpoint. Good reads
Okay, now there’s something you should hear if you haven’t already; The zombies in 28 Days/Weeks Later weren’t dead, they were infected persons, infected by the rage virus, as most people know when it comes to virus’s you can’t always cure them, you have to fight them out of your body. We already have virus’s that can turn somebody into a crazed state of mind bent on harming anything and anyone in his/her path. I’ll give you an example, Rabies, although rabies, (if untreated) will kill you after 3 days, it can drive a person into a psychotic state, another film that exposes this in a science-fictional way would be Quarantine, and Rec. I’m not certain on this one, but I was told that Mad Cow Disease is very similar with a more cannibalistic approach that comes along with the insanity, I don’t believe corpses can rise from the dead and have one goal: to eat the brains and flesh of the living, it makes little sense, especially since rotting of the flesh will be accelerated by something as simple as a hot summer day, and the bacteria would eat away at it. Also as you’ve stated, our military and police forces would crush the zombie hordes, but maybe, the plan isn’t to destroy the infection but test it; another example of a film would be The Crazies I believe it’s called. In this film people are able to use weapons and have the ability to think, but still want to kill the uninfected survivors, and the government actually had planned this out, once again a realistic approach to an actual zombie apocalypse wouldn’t be rotted corpses, but a virus, one that fucks with the head, and turns a person into a lunatic. Bath salts, another example, what if a new drug was exposed to the public? A pharmaceutical drug let’s say, as a cure to the common cold, it ends up turning people into aggressive killing machines, say a virus blocks a part of the brain out, signals aren’t sent or received to the pain receptors or the athletic part of the brain. Apparently humans only use about 20% of our true strength, shut the part off that controls that, now we have a lunatic bent on killing anyone he sees that can a mile in under a minute, or for ten miles straight at a constant speed that can also knock down a locked door with little issue, that’s the real threat that I can see possibly happening in the future. Anyway, I’m actually looking to write my first novel about a zombie apocalypse, I want to know all the reasons against and all the reasons it’s possible to have a zombie apocalypse to make this story as real as possible, if anybody has any suggestions email me here: superbadkneegrow@gmail.com
Thanks
A virus that eats bacteria called “Bacteriophage” would be enough to slow down decomposition since it eats bacteria :)
I think many of the more fast acting variations of the “zombie virus” are implausible, but if something were infect, and carry, before cause symptoms it could easily cause the breakdown of society. It’s been theorized that a mutant flu could wipe out a large portion of a country before anyone even knew they were sick.
Maybe in the 1910s. Any sort of dangerous birdflu outbreak today, even in africa, would be alerted to the world as quickly as one twitter message.
People only go to the doctor for what they have symptoms for. If you don’t feel sick but you are walking around actively infecting people, who then walk around infecting people,etc. ad nauseum…. These type of viruses don’t exist yet, but if they do and the human immune system isn’t equipped to fight them off… The Black Plague killed a lot of people, and though the standards for hygiene and medical care are much much much higher, we also live in far more densely populated cities and countries than ever before.
Perhaps the “dead” won’t walk the earth, but it could very well be the end of civilized human life as we know it.
Since you use “World War Z” in one of your section titles, you should really address that book, which directly takes on many or most of your objections to the zombie apocalypse in a very well thought-out way. You may disagree with the logic in WWZ, the book, but you need at least to take it on directly.
Some examples:
– Government cover-ups let the spread of virus reach critical mass. The Chinese Army keeps the spread of Zack under wraps long enough for mass infection world wide. So the army can actually be partly responsible for the outbreak.
– Early in Z outbreaks, people’s natural inclination to help rather than kill allows a lot more people to be infected. Bashing in the skull of everyone who acts strange, especially if you know them personally, is actually not normal human behavior, and won’t become so until well into the apocalypse. This sort of thing is well-covered in all Z lit.
– Conventional military doctrine is an abject failure against Zack, especially in force. This, combined with the first two, push the military to the brink. But ultimately the military regroups and wins.
– It’s hard to get to and live in icy wastes with cold and bears. In the Spring, Zack thaws out and surprises you. (Zombies that rot or run out of steam or are killed by certain harsh conditions is a subgenre, e.g. 28 Days Later.)
– One of the most interesting things in WWZ is the serious problem of the extremely large number (hundreds of millions) of zombies that have ended up underwater and continuously wash up on beaches, etc.
Gosh! I too was so surprised he hadn’t even bothered reading the book “World War Z”. One of the interesting points that pushes the military to the brink in the book (but not off of it), is the sheer *number* of zombies they have to deal with. Human wars at most have been fought between millions of participants, not hundreds of millions like a zombie war would involve, and the problem doesn’t become one of “can we kill a single zombie”, but “can we manage the logistics required to kill hundreds of millions of them”? The logistics in the end, is the real killer.
In what cities are you going to get hundred of millions of civilians coming at you all at once? Forget the fact that most military based are in sparse area.
Even so, a well coordinated correlation with tanks, air supplies, and rotating infantry can easily take out even hundred of millions of dumb crawling animals. There is just no way a bunch of mindless, weaponless zombies can take out any modern well equipped military base.
World War Z has been shown to be full of holes. The Author was more keen on altering facts to fit his scenario than actually be objective. Just look at the numerous posts online about his preferred zombie fighting weapons. Brooks particularly loses all credibility every time he opens his mouth in an interview or on a TV show. (Check out Deadliest warrior: zombies vs Vampires as an example. He is just a fan boy with no real expertise in anything).
The biggest issue with a Zombie virus outbreak is that there are no diseases with 100% infection, mortality, and transmission rates, and none that can kill or take over a host in seconds.
No nation to date, has been able to blackout media, social media, espionage, and word of mouth. (we have quite a few uprisings in the past 2 years to draw upon where this was tried and failed miserably) There is no way outside of science fiction that a government could cover up a zombie outbreak, especially when you have so many people trying to prove it exists beyond all logic.
Take into account urban warfare tactics of making choke points, kill zones, and using ordinance that can kill multiples of zombies with each fire, and you have an even more impossible scenario. Do you think that a horde of zombies can outwit a trap laid for them where they are lured/corralled into a killzone, where most thinking people can’t even see it coming? What in hell is any number of zombies going to actually do against a tank, APC, fighter jet, etc…
Sure Zombies are tough to kill, but explosives will rip them apart, and if you fill any body with enough rounds it will mechanically stop working. It does not matter how strong something is if it’s bones are in splinters or it’s ligaments are rotting.
Zombie Apocalypses are fun to imagine, but they require you to suspend belief and just enjoy the ride.
I don’t be leave in zombies i remember zombies were rising from the dead. I don’t be leave in the rising from the dead. There’s no fluids that functions the human body. No water no blood. I don’t see how it could happen without fluids to make the body function. For the zombie infections like resident evil and stuff like that. You hafe to shoot them in the head to kill them. If i blow them in half, cut their throat, shoot there guts out. How could they live? I just don’t see how it’s possible.
1)The most lethal weapon the infected could ever have IS TO STRIKE FEAR INTO THE HEARTS OF THEIR ENEMIES , THE INFECTED DONT FEEL FEAR RIGHT ?…It decreases humans’ morale in turn.
2)Humans are good killers of their own kind , but what they are killing isn’t (or was) human.
3)The Military’s numbers are much fewer than the actual number of people which (or most likely) are infected.
4)Zombies need headshots , right ? but soldiers were trained to double tap center mass … and by the time they learn where to shoot , the next thing they will shoot might be their own brain
5)THE ONLY THING ZOMBIES NEED IS THEIR OWN SELF .. WHILE THE LIVING THRIVE AND FIGHT WITH RESOURCES THAT DWINDLE ….
6)Humans may cooperate … but there is always that person who will or wouldn’t .
7)Humans have hard time coping with whateva is happenin .. Zombies dont cope …
once they are it .THEY ARE IT . :>
8)Humans who encounter infected are mostly to have casualties … or some surviving :(
9)No matter what , even if the military are engaging the infected effectively, Ammo would become scarce since they are not sure if what they have would be enough to fend off all of them .. and once one has died , the others lose their moral in return.
10)Humans tire out eventually, zombs dont ..
11)Military against infected in cities which are thickly populated have lesser chances of survival since they are fighting more than what they can .
13)Since the virus/fungus/pathogen/parasite may base on the brain …. which controls most of the motor functions . so if you want em dead, shoot em in the head. :)
14) The Infection starts first than how the authority responds to it .. which means by the time they know it … it is already in front of them O.o
15) I took out these points or thoughts from Max Brook’s WWZ book actually considering imma fan :) If im wrong in some parts … feel free to correct me
PLUS !! EVRY HUMAN THAT FALLS IS ONE MORE ZOMBIE ADDED
…. BUT TRY RESEARCHING ABOUT .
OPHIOCORDYCEPS UNILATERALIS .. .. anyway .. good job .. AND FO THAT , YOU HAVE A COOKIE ..Nice article by the way … soo informative
“(4)Zombies need headshots , right ? but soldiers were trained to double tap center mass … and by the time they learn where to shoot….. ”
When I was in the army we got taught to double tap the centre of mass, however if the target was hit but the shots had no visible effect we were taught to assume body armour was being worn and then aimed for the head.
Mind you, that was the Australian army which might have different teachings then the USA or were ever you’re writing from.
“9)No matter what , even if the military are engaging the infected effectively, Ammo would become scarce since they are not sure if what they have would be enough to fend off all of them .. and once one has died , the others lose their moral in return”
http://www.forbes.com/sites/ralphbenko/2013/03/11/1-6-billion-rounds-of-ammo-for-homeland-security-its-time-for-a-national-conversation/
I don’t think ammo will be a problem ;)
The USA would run out of ammo before you could kill 300 million zombies with head shots. Go stand at a firing range and fire off 10 shots at a stationary target at 50 feet. Then imagine 20 targets at 50 feet. A person can close a 50 foot gap in less than 5 seconds. How many head shots can you get on targets in 5 seconds before you get bit? If infected require head shots your only survival technique is to run.
I agree that the “walking dead” zombies would not exist in reality, however, a form of rabies, mad cow disease, or a mutant prion that removes pain receptors, induces extreme aggression and removes the ability to recognise friends and family, like in 28 days later, would be more plausible to exist and take over the world. Apart from the incredibly quick incubation/infection rate (20 seconds or something), this infection would easily overrun nations. In World War Z (the book, not the movie), the Z infection is helped by the black market organ trade and, as Bruce said, the natural instinct to help infected relatives, would both serve to assist the infection. The disease starts in a large population centre, like Europe, or Japan, China, South Korea, etc. and the first few infected don’t feel well, so they go to hospitals. When they turn, the hospital staff don’t know what is happening, and they are infected. Thus the infection radiates out of hospitals around the world. The military and police force would not be completely ineffective if they worked normally, but if the infection was large enough, members of these forces might even be infected, and could turn in barracks, thus infecting those forces. I think the problem with zombies is that the writers of the movie/tv show/book/etc. have to find a plausible way to overrun the military, but let the survivors, who most likely aren’t in the military, survive in the story. Anything the survivors can kill will probably be killed by the military first, and anything that can kill the military first will likely kill the survivors as well. This makes it hard to have realistic zombies. (spoiler for the walking dead begins). The idea from the waking dead about everyone having Wildfire and it activating when they die presents a relatively plausible solution, as deaths that don’t destroy the brain will result in walkers, which means that the thousands of deaths per day in the world will result in a massive outbreak. It doesn’t matter that they are stupid and slow when the panic sets in and more people die from the panic than actual zombies. The only problem is; how does everyone get infected? My thoughts anyway.
You forget the aspect of human v human which is acknowledged often as a bigger threat than the zombies themselves causing any sort of fight against the undead to be slowed. Plus the zombies can have an element of surprise like in Shaun Of The Dead, the infection starts slowly and quietly until the point of being enough to start slowly overtaking areas of population. Plus there’s probably more than a couple of thinking apes that would attempt to confront the zombies and end up losing. An apocalypse I agree is improbable but a zombie pandemic (if a disease could cause such a thing) wouldn’t be too unreasonable.
Either way great article.
If all the dead rose from the grave at the same time then I think we’d be in trouble.
All of this presumes that the gov’t wants to solve a crisis like this. It could be something that the Zero Population Growth crowd buys off politicians, mutates a strain of rabies or mad cow, and maybe passes a vaccine off as a cancer cure or other. Then people start getting sick and voila. The infected bite and infect others that refused the vaccine. The ZPG and politicians hide themselves and families off in secured locations prepared in advance. Eventually the infected die off and leave a world population more to the ZPG’s liking. Probably wouldn’t last more than 6 months to 2 years.
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the Zombie apocalypse would pale in comparison to the post disaster world shown in The Road. Starving humans in packs would do more to devastate humanity than any ZA. Forget about stocking up on machetes. Better to have plenty of high powered rifle ammo with a good scope and a ton of shotgun ammo.
How effective is ammo at night when your house gets surrounded by a pack of humans who light your house on fire with molotov cocktails?