032: How Does THE WALKING DEAD Zombie Virus Work?

In movies and TV, pandemics are pretty scary things. That's because they are. The only way to make them scarier? Zombies.

Now, ‘The Walking Dead' is arguably the most popular zombie story of our generation. Most of the story is centered around infection and how people get bit by zombies. So, I thought it'd be fun if we figured out how the virus works.

First, let's start with what we know. Well, from the end of season 1, when they all venture to the CDC, the Center for Disease Control and Prevention in Atlanta, we know that Rick and the gang figured out that Zombie Virus is indeed a virus, and everybody has it. No matter how you die, you come back. Unless your brain is destroyed. Now, is there anything in the real-world that even comes close to this? Well, there are a number of parasites that, after infecting their hosts, they effectively mind-control them. In the popular video game ‘The Last of Us', there's a genus of fungus called cordyceps which infects ants, mind controls them and bursts forth from the backs of their heads, to infect more unfortunate hosts.

There's even another parasite called toxoplasma gondii that affects an estimated one third of the human population. To complete its life cycle, it gets into the bodies of rats, mind controls them, so that they're no longer fearful of the smell of cat urine, which makes them get eaten more often by cats. The parasite then reproduces in the bodies of cats and eventually infects us. Now, is that a form of mind control? I think it is. But knowing what we do from the real world, ‘The Walking Dead' virus doesn't exactly control a living host, and the chief concern is getting bit by a zombie and getting infected. Now, in reality, dying from a virus that you already have doesn't really make sense. When you already have a virus, but it's not affecting you, that's called a reservoir. For example, we think that bats are a reservoir for the deadly Ebola virus. That means that Ebola is definitely coursing through their veins, but they don't die from it. Similarly, it'd be odd if getting bit by a zombie that has the zombie virus would kill you with that virus, if everyone already had it. So, if all of humanity is already a reservoir for the virus in ‘The Walking Dead', it has to be something else that makes the bite so deadly. I think it has something to do with the bacteria in their mouths. In a world where nothing works, it would be nearly impossible to get anything like proper medical care, bandages, antibiotics, medications, even if you had your own octogenarian veterinarian on hand.

So, what in real life kills with a dirty mouth? Well, famously, the giant lizard called Komodo Dragons have enough bacteria in their… Wait, wait a second, that's not quite right. New research has actually come out showing that Komodo Dragons do kill with venom found in the glands of their mouth. So we're gonna have to think of something a little bit different for that. How about, natural disaster victims? Unfortunately we know when we pick up dead bodies from natural disasters that they can harbor sometimes deadly bacteria and viruses like tuberculosis and even Ebola. If we consider a dead and decaying body to have some of that bacteria and virus in their mouth, it stands to reason that, if you got chomped on in the arm or the neck and it went straight to your bloodstream, that would almost be a death sentence. Sorry about that leg, Hershel.

So, what do we know? Well, although there are real world parasites that zombify their hosts, this isn't quite what ‘The Walking Dead' had in mind when it created its own zombie virus. That's not quite how viruses work. However, we can guess at what really kills you in ‘The Walking Dead', and it seems to be a dead, diseased, decaying mouth chomping down on you, and not having access to the right medical care or supplies to treat it. Why? Because Science.