Tag Archives: Zombie Disease Transmission

How Outbreaks Spread … Or Why I’m Moving To St. Helena Just In Case There’s A Zombie Apocalypse

16 Dec

For there to be a zombie apocalypse, the disease which turns people into zombies must spread. Traditionally, it’s always been assumed that diseases spread geographically, and that the closer you are to the source of an epidemic (whether zombie-related or not), the sooner you are likely to encounter it. For most of human history this was, indeed, the case. However, in the last fifty years or so this has gradually changed, and now things are quite different. This is because, thanks to the ubiquity of modern air travel, the way the world is connected has changed. This has led to a disconnect between the geographic distance between any two points on the planet and the transmission distance (which measures the ease by which a disease can get from point A to point B).

This means it is now easier for a disease to spread from London to New York, despite the several thousand miles of water between them, than between London and Cape Wrath at the far northwestern tip of Scotland, which is only a few hundred miles away on the same island, but which has no direct connections of any kind to London (the two are not even connected by road). Indeed, a disease might find it easier to get from London to Sydney, Australia, on the other side of the world, than from London to Cape Wrath because of the way airlines now connect the world.

While this might be intuitively obvious once someone points it out, it’s only recently that this has started to be incorporated into our understanding of how diseases spread. Of particular interest here is the work of theoretical physicist Dirk Brockmann, who, along with a number of colleagues, has created a mathematical model of how the connectivity resulting from modern air travel affects how diseases, such as SARS, swine flu or (in theory at any rate) a zombie virus, spread around the world, but you don’t have to understand maths to be able to see what’s going on. This is because he’s used his model to produce some really beautiful and interesting videos, like the one below, to show what’s going on.

The video below starts with an outbreak of a disease in Atlanta, Georgia, and shows how it rapidly spreads around the world along the air routes which radiate out from this air hub.

For those of us interested in creating zombie apocalypse stories, these new models of how diseases spread in the modern world can help us create more realistic scenarios for how a zombie epidemic caused by a disease might be transmitted around the world. For those who worry that it’s only a matter of time before a zombie apocalypse actually happens, it can also be very informative as it highlights where in the world you’d have your best chance of avoiding being caught up in the outbreak.

For this reason, I’ve been looking around for possible places to relocate to just in case there’s a zombie apocalypse looming over the horizon, and based on the connectivity suggested by the above model, I think I have the perfect place: the small tropical island of St. Helena in the South Atlantic. It has no airport and is two days by sea from the nearest airstrip (on Ascension Island, which, in itself, is hardly a major air hub!). I think I’d be pretty safe there. As it happens, I’ve also been there as part of my day job as a marine biologist, and I can tell you from experience, it’s a really nice place and I could think of a lot worse places to hole up while waiting for the world to come to an end.


If you want to find out more about Dirk Brockmann’s research on how diseases spread, click here.

From the author of For Those In Peril On The Sea, a tale of post-apocalyptic survival in a world where zombie-like infected rule the land and all the last few human survivors can do is stay on their boats and try to survive. Now available in print and as a Kindle ebook. Click here or visit www.forthoseinperil.net to find out more. To download a preview of the first three chapters, click here.

To read the Foreword Clarion Review of For Those In Peril On The Sea (where it scored five stars out of five) click here.

The Importance Of Transmission – Or How Could I Catch A Zombie Disease?

25 Feb

For a zombie apocalypse to happen, you need two things: Something to turn people into zombies and a way this can be transmitted from person to person. Without transmission, any zombie outbreak will have, if you excuse the pun, little bite to it, and this is what I want to consider here. So what do I mean by transmission? Well, transmission is how whatever’s turning people into zombies gets from one person to another. The method of transmission will determine both how easily it can spread and how easy it will be for you to avoid picking it up. Here, I’m primarily thinking of diseases or parasites that turn people into zombie-like creatures, whether natural or man-made) rather than something that would raise the dead (this is because I’m trying to keep it biologically feasible). Also, I’m not going to consider other things that could turn people into zombies (such as chemicals).

So how could a zombie disease be transmitted? The traditional route is through a bite that breaks the skin, allowing saliva from an infected person to get into the blood stream of someone they attack. This is certainly a well-established way of diseases passing from one person to another. For example, this is the way that rabies (probably the closest thing in the world today to a real ‘zombie’ disease) is transmitted from one person to another. However, transmission through bites is actually quite an inefficient route for a human disease to move between victims. This is because human teeth are pretty poorly adapted for biting and you have to bite someone pretty hard to get through the skin. Also, this mode of transmission would be easily foiled by something as simple as a thick leather jacket (think of the kind stuff that bikers traditionally wear). This means that any zombie disease that only spreads through bites will spread slowly, at least at first. Only once you have a critical mass of infected people will it really take off. It would also be quite easy to avoid picking up a zombie disease from a bite – you just don’t let someone who’s infected close enough to get their teeth into you.

Other less tradition routes of transmission could allow a zombie disease to spread both with greater ease and much, much faster, making it easier for a zombie apocalypse to get off the ground and bring the world to its knees. For example, a disease can also spread through contact between bodily fluids and what are known as mucosal membranes (things such as eyes, noses and mouths) or existing wounds. This would mean that someone could get infected not just from a bite but also from things like blood and saliva getting onto your face when you’re bludgeoning in the head of the person trying to bite you. This mode of transmission features in the film 28 Days Later (one of my all time favourite post-apocalyptic stories ) where one of the characters is infected with the rage virus by a drop of blood falling into his eye, and would allow the disease to spread a lot quicker and easier. This is because killing people infected with a zombie disease will be very, very messy and there will probably be blood and guts flying everywhere. It will be much harder to protect yourself because all it needs is one drop of blood to end up in the wrong place and you’ll be a goner.

Similarly, a zombie disease could go air-borne. This would make just being in the proximity of someone who is infected very dangerous, after all they wouldn’t need to bite you, just breathing in your general direction might be enough. If this is the case, you’d probably never want to go outside without a face masks and filters to avoid catching it. As we all know from our own experiences with flu, air-borne diseases can spread very fast and one person can infect many, many others in a very short space of time. This makes the prospect of an air-borne zombie disease extremely terrifying. I mean, what if it was as easy to pick up as the common cold?

There’s also the possibility that a zombie disease could be water-borne. Take something like typhoid or dysentery. These are normal diseases you can pick up from unclean water but what if you could contract a zombie disease in the same way? If this were true, one infected person could infect many, many others without even going near them. It would also be much, much harder to avoid – All you drinking water would have to be passed through something like a reverse osmosis machine to filter out the disease before you’d know it was definitely safe to drink and such machines are not exactly common outside of the sailing community. Just think what would happen if the public water supply somehow got contaminated (maybe by the body of an infected person ending up in your local reservoir). This means that a water-borne zombie disease could start an epidemic very easily. However, there’s still at least a chance you could avoid catching it if you have the right equipment.

The last possible mode of transmission I want to consider is a vector-borne zombie disease (something my fellow writer Jack Flacco reminded me about today in a comment on another of my posts). This is a disease that can be spread not just from bites from other people but by bites from other animals too. The vectors wouldn’t catch the disease so they wouldn’t become zombie animals; instead they’d just transmit it from one human to another. Think malaria and mosquitoes here. A vector-borne zombie disease would be truly frightening and almost unstoppable. One vector could infect many, many people and, depending on what the vector is, it could be almost impossible to avoid them. Almost anything that is small and feeds on human blood could be a vector for a zombie disease but I’m only going to consider two of the most common: Ticks and flying insects.

If a zombie disease was transmitted by ticks (small, blood sucking relatives of spiders), then it’s likely to spread slowly but inevitably, especially in areas of open countryside (the model here is something like Lyme disease). However, they are relatively easy to avoid by keeping away from such habitats and doing things like making sure you don’t leave your legs uncovered. With a tick-borne zombie disease, what you’d probably see is the disease flaring up here and there on an unpredictable basis. This would make fighting it very difficult as we’d never know where it would strike next.

If a zombie disease was transmitted by flying insects, we’d see a very different pattern of infections. Once someone in an area got infected with a zombie disease, it would rapidly spread from person to person whenever an insect bit one person and then another. This would result in a disease front that spread rapidly across a region. People fleeing from infected areas would only make the spread happen faster. And no matter where you were, you’d never be safe from the risk of infection. I mean, have you seen how hard it is to keep every mosquito, midge or fly out of your house on a hot summer’s night? A zombie disease that was transmitted by flying insects would be a truly terrifying prospect because it would be virtually impossible to either stop or avoid.

So what’s the conclusion of all this? Well, if a zombie disease were to ever appear, you’d better hope that the only way it’s transmitted is through biting as that will give you your best hope of being able to both avoid it and beat it. If it develops the ability to spread by any other means (and why wouldn’t it since many other diseases do?), you might not believe it to be possible, but you’ll be in even deeper trouble than you were before!

From the author of For Those In Peril On The Sea, a tale of post-apocalyptic survival in a world where zombie-like infected rule the land and all the last few human survivors can do is stay on their boats and try to survive. Now available in the UK, and available as an ebook and in print the US from the 21st March 2013. Click here or visit www.forthoseinperil.net to find out more.