Last week, I took a brief hiatus to swim, sunburn, and get a little reading in. You can imagine my surprise when not one but two books I read referenced prions: DEARLY, DEPARTED by Lia Habel has prion-zombies, and LOSERS IN SPACE by John Barnes has a brain destroying drug that affects prions. (And both books are seriously kickass, BTW.) I assume this wouldn’t be a big deal to most people, but it really stands out to me. Why? Before I became a full time writer, I managed the national center for research in prion diseases. My books may be full of pseudoscience, but there’s some real life inspiration underneath. Today, I thought I’d talk a little about why prion diseases are often used in zombie books.
What’s a prion?
A prion is a protein that exists in your brain. That’s right–you can’t GET prions; you already have them. We all do. But prion diseases happen when the protein becomes malformed. You can think of it like a puzzle piece. The shape is really important to what a protein does, just like the shape is really important for a puzzle piece. Minor changes like cutting the corner off a piece aren’t going to interfere with its place in the puzzle. But if you really dork up the piece, it’s not going to fit into the puzzle. And when the prion protein gets out of shape, it’s an understatement to say that bad things happen.
The misshapen protein (you can really impress people and call it by its scientific name, the scrapie prion protein) is infectious, which is a fancy way to say that it transforms any normal proteins it comes in contact with so now they’re abnormal too. And once those abnormal proteins reach critical mass, the host will start showing symptoms. Unfortunately, without an effective treatment, the symptoms progress until the host dies.
There are a variety of human prion diseases, only one of which is mad cow disease. You can also develop a spontaneous form or inherit it from one of your parents. Prion diseases also affect animals like cattle, deer, and sheep.
Why use prions in a zombie book?
Prions have been used to explain zombification in a variety of books. I’ve already mentioned DEARLY, DEPARTED; another that comes readily to my mind is PATIENT ZERO by Jonathan Maberry. Why are prions so popular as a zombie theory? I think there are a few reasons for that. One is that the abnormal prion protein multiplies so easily. Only a small number of infectious particles are needed to transmit the disease, and they’re really difficult to destroy. That would make it potentially transmissible by zombie bite. But please note that the studies of real cases that I’m aware of found that saliva was not infectious. I’m talking about how the real science could be used to inspire a pretend zombie theory, and I want to be absolutely clear about that distinction.
Prion diseases affect brain function. Common symptoms include dementia, problems walking, problems with speech, and involuntary jerking motions. It’s really a terrible series of diseases, and as I said above, they are sadly fatal. But again, these symptoms can present a jumping off point for a zombie theory. In a book, I might say that my prion-inspired zombie virus results in dementia and aggression, which means the infected would be more likely to get into fights. And if it’s spread by bodily fluids, that’s a transmission vector.
Prion diseases have also been demonstrated to spread quickly through a population under the right circumstances. A form of prion disease called Kuru completely destroyed a tribe in Papua New Guinea. How did this happen? One of the tribe members developed a prion disease. This tribe practiced ritual cannibalism. After death, the remaining tribe members consumed infected brain matter and became infected. And so it spread. I don’t think this bit requires explanation, I think the zombie inspiration is pretty overt, don’t you?
And lastly, there’s a lot about prion diseases that we don’t know. The fact that they’re spread by a protein rather than a bacteria or parasite has been controversial. The fact that a majority of the cases we see are apparently spontaneous has led to a lot of searching through patient histories to find patterns. These things are incredibly important to research and explore, and hopefully filling in more answers about how these diseases work will eventually lead to an effective treatment. And perhaps even silly zombie books like mine will help bring attention to a very real problem. I certainly hope so.