‘The Walking Dead’: 5 Theories About the Origin of the Outbreak

The Walking Dead

The Walking Dead | AMC

Thanks to The Walking Dead and Fear the Walking Dead, we have a pretty good idea of how things might go down in the event of a zombie apocalypse. Since 2010, AMC has given us an intimate look into Robert Kirkman’s frightening landscape. Although it doesn’t always make sense, Kirkman’s vision has offered up a clear vision of what humanity might look like when brought to the brink.

One thing that the franchise hasn’t explained, though, is exactly how the undead came to be in the first place. And since the series’ creators have said they won’t tell us why the dead started to come back to life, fans have come up with some pretty creative explanations all on their own. Some — like the one that lays the blame on Breaking Bad‘s Walter White — are pretty out there. Others sound not only plausible, but scarily realistic. Here are five of the most intriguing theories about the origins of The Walking Dead‘s outbreak.

1. It was immunizations

A zombie child in a pink robe from the first episode of AMC's 'The Walking Dead'

The Walking Dead | AMC

Every year, millions of Americans take a trip to their doctor or local pharmacy to get immunized for a range of communicable diseases. And while we’re told this is the best way for us to stay healthy, there are some Walking Dead fans — including a pretty famous one — that think this practice may have actually led to the rise of zombies.

Fear the Walking Dead actor Cliff Curtis recently speculated on what may have kickstarted the outbreak, and his rationale was actually fairly sound. “We’ve basically become over-immune,” he told Collider, “and our immune system takes over and refuses to let the body die.” There are some holes in that concept — for one, there are plenty of people out there who don’t get vaccinated, and the zombie syndrome seems to be universal. But since we live in a world where prescription medicine abuse is becoming a real epidemic, there is some precedent — or at least real-world correlation — to the idea of a crisis arising out of well-meaning medicinal intervention.

2. It was in the drinking water

Maggie, Glenn, Eugene, Tara, Rosita, Noah, Sasha, Father Gabriel, Abraham, Michonne, Carol, Rick and Carl stand around bottles of water in a scene from the fifth season of 'The Walking Dead'

The Walking Dead | AMC

There are a few core things that every human needs to survive, and one of them is water. So, it stands to reason that perhaps the origins of The Walking Dead‘s zombie apocalypse lie in that essential liquid. Some fans have explored the idea that there was a mineral, pollutant, or some other nefarious element in the drinking water that triggered the zombie tendencies in the human brain. It’s certainly a timely theory — after all, in the last year alone we’ve seen more than one serious health crisis arise due to unsanitary drinking water in the U.S. But given that each town or city has its own water resources and methods of filtration, it’s hard to see how it could have instantly become a nationwide pandemic.

3. It was Mother Nature’s revenge

Travis (Cliff Curtis) stands in front of a blackboard in a scene from the first episode of 'Fear the Walking Dead'

Fear the Walking Dead‘s Travis | AMC

The concept of man battling nature is nothing new — in fact, it’s the hallmark of many classic tales throughout time. But is The Walking Dead also trying to teach us a lesson about our relationship to the environment? Some fans seem to think so — and they’ve used an early scene from Fear the Walking Dead to help make their point. When we first met Travis, he was teaching his students about Jack London’s To Build a Fire and reminding them that when man goes head-to-head against the world’s natural elements, “nature always wins.”

Could this mean that the zombie apocalypse is simply Mother Nature’s way of fighting back against a rapidly growing population and the detrimental effects of industry? Neither series has dropped all that many hints aside from Travis’s initial reflection. But there’s also no arguing that nature — the kind that transforms humans into flesh-eating zombies with little warning — is certainly winning in The Walking Dead universe.

4. It was biological warfare

Survivors walk past dead bodies as they head toward the CDC in a scene from 'The Walking Dead'

The CDC on The Walking Dead | AMC

While many fan theories center on the idea of a somewhat innocuous cause for The Walking Dead‘s zombie apocalypse, others seem to think there was something a bit more insidious at play. What if it was an act of war? Some fans have postulated that the outbreak stems from some kind of biological weapon — either used against us in retaliation, or accidentally unleashed upon us by our own government. While it may sound a bit paranoid, this theory has played out successfully in other horror stories — the superflu virus in Stephen King’s The Stand, for example, was mistakenly carried out of a government compound. It’s also one that would be especially hard to prove, since we’ve seen so little evidence of government control or influence in either The Walking Dead or Fear the Walking Dead thus far.

5. It was aliens

An alien from James Cameron's sci-fi thriller, 'Aliens'

Aliens | 20th Century Fox

Any sci-fi fan knows that there are zombie stories, and there are alien stories, and rarely the twain shall meet. But wouldn’t it be kind-of awesome if they did? Some Walking Dead fans seem to think there could be some extraterrestrial elements in play in the series, given how suddenly and comprehensively the zombie outbreak hit humanity. According to one theory, aliens hell-bent on taking over Earth and extracting its natural resources could have disseminated the epidemic to more-or-less wipe the human race off the planet without destroying it. How? They’re not really sure. But it’s a cool idea, anyway.

Follow Katherine Webb on Twitter @prufrox

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