Don't Panic

A while ago, after watching an episode of The Walking Dead, I realised that my area had no zombie apocalypse evacuation procedure in place. I honestly don't know why it hadn't occurred to me before. So, borrowing a little from films and television, I created one. I'm not going into detail here, but it's basically a three-step process.

1. Tool up. Grab anything that could be used to decapitate a zombie, destroy its brain, or just incapacitate it long enough for you to run to safety.
2. Get the hell out of Dodge. Zombies aren't smart, co-ordinated or especially fast, but they can swarm. If enough of them swarm around a house, eventually, they'll get in. The fact that zombies can't feel pain allows them to be utterly relentless (to a point). I chose a local bar as my safe place. Nice thick doors and gates, a selection of places to barricade oneself in and a lovely view of the river* make it ideal. The large stock of beer doesn't hurt, either.
3. Sit tight. Whatever remains of the government and armed forces will hopefully be able to bring the undead threat under control. If not, the bar becomes humanity's last refuge. On that street, at least.

Zombies taking over the world may not be terribly likely, but you never know, and there's absolutely no harm in being prepared. 

 

Some time later, me being me, I started to wonder just how likely a zombie apocalypse is. So, basically, I identify a possible threat, figure out what to do if it happens, and then worry about it. Anyway...

Before we work out how likely it is, we must first work out exactly what a zombie is. If I've learned one thing from television (and it's entirely possible that is indeed the case), a zombie is a dead human, somehow reanimated. There are two ways to look at this; the first is that it is, like that film said, the result of hell being full, forcing the dead to walk the earth. If this is what makes zombies, then there is no need to worry. O r at least no point. If the devil can't do anything about the overcrowding, then there's probably not much God can do, either, and if he can't do anything, we're pretty much shafted. In the event of a zombie apocalypse, open a cold one and wait for death. Take pictures.

The other is some sort of pathogen. A virus, perhaps, capable of hijacking the human brain and shutting most of it down. The brain, in full working order, is what makes you you. It is what makes you breathe, eat, move, shout at the TV and think. Thing is, not all of it is essential. If the mind is Windows 7, then the brain stem is the BIOS. It is what gets you up in the morning. Neurological functions located in the brain stem include those necessary for survival (breathing, etc...) and for arousal (being awake). Without the other grey bits, you cease to be an individual human being and become simply a being, intent on nothing more than survival. But don't panic just yet; while something like eastern equine encephalitis can cause serious brain damage, no virus capable of shutting down all but the brain stem currently exists and we'll never see a zombie virus, because the minuscule genome basically rules out a virus complex enough to infect a host, set up camp in the brain and set about rewiring. So, sorry, my fellow The Walking Dead fans, but zombification caused by a virus is impossible.

A parasite might do it. Something like Toxoplasma Gondii, perhaps. This is a parasite which lives in the digestive system of cats, shedding eggs which can be picked up by rats. An infected rat still looks and behaves the same, except it shows absolutely no anxiety when it smells cats in the area. Instead of running for their lives, they can actually head towards the predators, apparently curious. Or maybe in some kind of trance, repeating to themselves “Must... get... eaten...”. All it would take for the parasite to cause serious behavioural changes (aggression, cannibalism, etc...) is a little genetic fiddling. Considering the amount of research being done on biological weapons these days, I wouldn't be amazed to discover that Toxoplasma Gondii 2.0 (Zombie Version) already exists. Oh, by the way, it's estimated that half the human population of earth is already infected. Toss a coin to see if you're one of them.

Or maybe we should be worried about neurotoxins. Several poisons exist which are capable of slowing the metabolism to a point where a person can pass for dead. The 'corpse' can be brought back using alkaloids, leaving them in a trance-like state with no memory, but capable of basic tasks like eating and walking. A man pronounced dead by two doctors in Haiti in 1968 was discovered shuffling around the village, groaning, eighteen years later. He, along with others, had been turned into a mindless slave and put to work on the sugar plantation.

Or there's my personal favourite: nanobots. Self-replicating nanobots, carried in the bloodstream, could, with the right setup, cause the necessary changes in behaviour and could conceivably also be found in saliva, making transmission by bites possible. Good news, though: the technology is nowhere near advanced enough. Yet.

When I started thinking about whether or not a zombie apocalypse is possible, I began some in-depth research (okay, I read some articles and had a coffee) and discovered that there are a few ways to cause zombie-like symptoms in living people. But I have so far found nothing that can induce that most recognisable of all symptoms: decomposition. It's a pretty common theme in zombie flicks. The zombies are always slightly grey, they have serious cataracts and, every now and then, something falls off. A true zombie would have to actually die, while somehow remaining capable of walking, groaning and eating brains and, as far as I'm aware, this is simply not possible. So, how likely is a zombie apocalypse? It's not. Not even a little bit.

But what if I'm wrong? What if the dead did somehow get up and walk? How worried should we all be? Not very. Firstly, nearly every country in the world has an army and if soldiers can be trained to fight people who have guns and explosives, they can surely take care of people with no heartbeat, who are armed only with... um... arms. And lets not forget the survivalist nutcases. Their decks have been well shuffled, but they know one end of a high-powered rifle from the other. Just stand behind them.

While the armed forces are working on eradicating the undead hordes, institutions like the World Health Organisation will work to prevent the plague spreading. The CDC already has advice on what to do in the event of a zombie apocalypse. Check out http://blogs.cdc.gov/publichealthmatters/2011/05/preparedness-101-zombie-apocalypse.

The next problem facing Mr and Mrs Cadaver is that they're an easy target for predators. I know, bears probably aren't much of a problem on your street, but smaller creatures, that wouldn't normally go for a living person, will find zombies irresistible. Stray dogs won't take long to work out that zombies are basically walking dinner. Flies like to lay eggs in dead things, so zombies that haven't been torn apart by dogs will soon have maggots falling out of them. Which leads me to the small matter of decomposition.

The immune system is a thoroughly impressive thing. We are constantly under attack from various malevolent microbes, and the immune system is constantly defending against them. Until we die, that is. Your immune system pretty much stops when your heart does, which is not something I'm terribly worried about. As far as I'm concerned, after I'm dead, every bacterium in the world has my full permission to chow down. But the complete lack of defences is a zombie's biggest problem, apart from the fact that their sole means of reproduction is also a major food source and their main predator. The trouble starts from within. You know the so-called 'good bacteria' in your digestive system? With no immune system to control them, they'll soon get to work on the (very) soft tissue of the intestines. While they're busy eating and producing CO2 and methane, the exposed surface of the eye is fair game for whatever lands on it. With no blood pressure, the smallest wound (which the zombie can't heal) is basically an open door. Within the first few days, Mr Zombie will be a hive of germ activity, with each micro-organism taking away more and more flesh. After a week or so in a warmish climate, putrifaction has already happened. Possibly sooner. This ain't pretty. Basically, subcutaneous tissue liquifies, with the skin holding it together, so the whole thing is basically a big bag of putrid matter. Assuming the putrifaction isn't what does for the zombie, there's a very real chance that the gas build-up in the abdomen will cause the lower torso to burst. 

 

Long story short: the 'life' expectancy of a zombie is a week or so, during which time they will pick up all sorts of injuries which will never heal, gradually becoming slower and weaker, before eventually falling apart, mid-stride. After a fortnight, and possibly not even that long, the zombies that haven't been eaten by dogs, colonised to bits by flies, blown to pieces by the army, decapitated by keen amateurs, or just swept away by the river they fell into, because they didn't realise what it was, will die for good. Those of us who survive the 'apocalypse', and that'll be the vast majority of us, will sweep up the bits, hose down the streets and get on with our lives. Zombies, even if they were a possibility, would be about as dangerous as rabid cows.

Just in case I'm wrong, buy a crowbar. You'll know what to do with it, when the time comes...

*Yes, I was joking about the 'lovely view'. Although I suppose there are worse things to look at, while you're waiting for a zombie apocalypse to blow over.