"The Last of Us" is an almost-perfect metaphor for climate change, but it gets one thing wrong

Climate change is such a vast, all-encompassing topic that it is difficult for the human mind to fully grasp. Try to discuss the catastrophic implications of a 2-degree Celsius increase in average global temperature to an uninvested stranger, and you're apt to see their eyes roll back in their head. It's just a number or a temperature graph. What does it have to do with anything? Even many climatologists to whom I've spoken, whose job it is to study global temperature trends, struggle to picture the enormity and cascading consequences of this slow-moving disaster. It boggles the mind; and yet, no one is acting fast enough.

Unless a wildfire or flood is serious enough to splash across national headlines, the day-to-day effects of climate change aren't exactly in your face. A heat wave here, a crop failure there. These are slow, often isolated changes, sometimes referred to with abstract terms like "anthropocene," attached to seemingly distant dates like 2050 — a year when, if we change nothing about energy policy, greenhouse emissions are projected to increase by 50 percent from today. Sure, we're going in the wrong direction — but that's roughly three decades from now. This can all be easy to ignore.

So it is remarkable when a piece of art comes along that makes the incomprehensible comprehensible. The new HBO drama series "The Last of Us" is not only a masterful adaptation of an innovative video game universe, it is an (almost) perfect metaphor for climate change. The show helps visualize a difficult to grasp concept through the use of an infectious fungal disease without being preachy about it — which sets it apart from films like "Don't Look Up," which used a deadly comet as a stand-in for climate change.

The show trades immersive action for evocative drama and somehow doesn't stumble over itself, a testament to the show's creators Craig Mazin, of "Chernobyl" fame, and Neil Druckmann, the mind behind the video game. The duo are clearly aware of the game's broader implications. Mazin recently told Wired, "I think the thread underneath ["The Last of Us"] is: You don't want to be too successful on planet Earth." Mazin added: "I'm not an anti-progress, back-to-the-Stone-Age guy. But we must regulate ourselves or something will come and regulate us against our will."

The general plot is explored more deeply in a review from Salon's Melanie McFarland, but briefly summarized, it is a story about violence and unconditional love set against a post-apocalyptic landscape devastated by a zombie-like fungal outbreak. When this fungus enters the brain of a human, it's like the opposite of "magic" mushrooms, as it turns people into violent psychopaths that spreads the pathogen further. Talk about a bad trip. It's a pretty smart take on zombies, in my humble opinion, especially given there's a real fungus called Ophiocordyceps unilateralis that can turn insects into their little slaves.

Some recent apocalypse cinema avoids fully explaining why the apocalypse occurred, just that it did; "The Road," a Cormac McCarthy book turned film, is a prime example. (It's so common that film fans even have a name for this trope: "unspecified apocalypse".) Thankfully "The Last of Us" TV show bucks this trend for the adaptation, as it makes very clear how global warming is implicated in the collapse of civilization.

In the first five minutes of the show (not really a spoiler — I promise) a fungal expert explains in 1968 that a pathogen like Cordyceps could burst forth from nature and devastate humanity in a manner much worse than a viral pandemic. But the scientist emphasizes that it would require the conditions of the planet warming a few degrees. How ominous.

Fast forward to 2003, and exactly such an outbreak occurs. All at once, people around the globe become sick with a new fungal disease that controls their bodies and forces them to attack the survivors. In less than 24 hours, the world goes from functional to absolute bedlam as indeed, climate change becomes the catalyst for a fungal disease that nearly wipes out humanity.

This is a brilliant message to include in a show as popular as "The Last of Us," which is currently experiencing record-breaking and enthusiastic reviews from critics and fans. It is not out of the question that humanity might someday exist in a similar world to Joel and Ellie, the main characters in "The Last of Us," if we don't take drastic measures to avert climate change. Experts know that pandemics are directly tied to climate change. The reason has to do with animals: many diseases that spread to humans start out in other animals, animals that hopefully stay far from humans most of the time. But climate changes can alter the migration patterns of animals. Likewise crop failures can prompt humans to search for food from exotic animals they may not normally eat. Experts believe that hungry humans that had to resort to eating bushmeat — meaning wild apes and the like — is how HIV's ancestor virus jumped over to humans.

Deforestation, too, can exacerbate the spread of disease: the more nature that humans destroy, the more the viruses that exist in those environments will go looking for new hosts. This phenomenon, known as zoonotic transfer, has been happening since the dawn of agriculture and is only accelerating as climate change worsens.

Hence, "The Last of Us" is relevant because many pandemics can be directly tied to climate change — but again, it's not always easy for the general public to make this connection.

Indeed, public health and ecosystem collapse are deeply linked. One example is nipah virus (NiV), a devastating disease with a fatality rate between 40 to 75 percent. For comparison, SARS-CoV-2, the virus that causes COVID, has a fatality rate of 1.1 percent in the U.S. NiV is so deadly because it worms itself into the brain and causes it to swell, triggering fever, headache, drowsiness, disorientation, and mental confusion, which can progress to coma and death. There are no vaccines or treatments and survivors often experience lifelong disability or personality changes.

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This virus is so terrifying that it makes SARS-CoV-2 look like a mild cold (though it really is not). Nipah virus hasn't been a huge problem yet — emphasis on yet — because thankfully it has trouble spreading from human to human. It has only caused a few hundred deaths to date, but it is now a seasonal illness that could expand its range if we're not careful. Unsurprisingly, nipah virus was the inspiration for the 2011 film "Contagion," in which an extraordinarily deadly virus kills a lot of people.

NiV is one of the most clear-eyed examples of a virus jumping from animals to humans. Scientists believe it originated in fruit bats but spread to pigs and then humans. This chain of dominos goes back to Indonesia's abysmal forestry practice in 1997, when the island nation slashed and burned more than 5 million hectares of rainforest, trees that were already crushed by an El Niño-related drought. The resultant cancer-causing smog created "the most severe haze ever known in Southeast Asia," according to researchers at the University of Malaya in Malaysia. Bats that were fleeing this human-caused disaster roosted above pigsties in Malaysia. The swine below ate the bats' feces, allowing the virus to hop from one mammal to another to us.

Similar transfers are bound to keep happening as we destroy more animal (and virus) habitat. In fact, three out of four emerging diseases come from animals. Similarly, the current pandemic may have been spurred in part by climate change. Like many diseases including NiV, Ebola, SARS-CoV-1 and MERS, SARS-CoV-2 more than likely originated from bats. As The Atlantic's Ed Yong describes it, we're living through the "pandemicene," a period marked by more and more pathogenic outbreaks.

"Many scientists have argued that climate change will make pandemics more likely," Yong explained, "but a groundbreaking new analysis shows that this worrying future is already here, and will be difficult to address."

Viruses are invisible to our eyes. Like climate change, that can make it easier to ignore. We need compelling art like "The Last of Us" to help make these connections, between an abstract threat and a real violent end for humanity. But unlike in the first 30 minutes of the TV show, there will be no "zero day," no sudden switch from calm to chaos as throngs of people flee movie theaters or planes drop from the sky.

Instead, our baselines for normal will continue to slowly shift, so that we won't really notice that it's now unbearably hot the entire summer or that winter is mostly a feature of the past, freak storms aside. The world we know won't disappear in an instant — it will be a gradual, pathetic limp toward oblivion. In fact, the world we knew is already gone. Climate experts I have spoken with repeatedly emphasize that our climate has already changed. It's not some abstract future scenario. It's the present, yet we're still punishing the people that protest this business-as-usual bullshit.

As glaciers evaporate, it could pour more novel pathogens like nasty viruses into the mix. As the coral reefs die from increased global heating, the fish in the open ocean will similarly disappear and the billions of people whose primary source of protein comes from fish and other aquatic creatures will either starve or put even more pressure on agriculture. If growing food in fields continues to decline, as it is currently in places like the California's San Jaoquin Valley, once one of the most fertile regions on Earth, billions of people will starve. As the cost of food continues to skyrocket, it will push more people into homelessness. Governments appear to be trying to "solve" this problem by shuffling unhoused people into institutions, which feels eerily like the first stages of being forced into a "quarantine zone," as in the show.

While a fungus that controls human minds is likely to remain complete science fiction, fungal pandemics are a real thing and increased global temperatures are giving fungi more opportunity to spread. "The Last of Us" nailed that one. Mushrooms, molds and other fungi tend to like warmer environments. And toxic fungi that can infect humans like Aspergillus fumigatus, are becoming "increasingly common" according to the World Health Organization.

"Despite the growing concern, fungal infections receive very little attention and resources, leading to a paucity of quality data on fungal disease distribution and antifungal resistance patterns," the WHO warned in its first-ever global effort to rank fungal pathogens by threat level, a call-to-action released in October 2022. "Consequently, it is impossible to estimate their exact burden."

A fungal pandemic or even another viral one is hard to predict, but it won't look like TV. That's OK. We need forward-thinking media to illuminate hard-to-grasp concepts like climate change and pandemics. It's called a metaphor, I guess. And "The Last of Us" does a decent job, accelerating the timeline from disaster to post-apocalyptic wasteland for dramatic effect. That's forgivable.

Despite my own use of the term "post-apocalyptic" in this essay, it's not really a terminology that makes much sense when applied to TV shows or games like this. The modern meaning of apocalypse as a "cataclysmic event" or "imminent end of the present world" is a 19th century invention. The word actually comes from the Greek apokalyptein which means to "uncover, disclose, reveal." An apocalypse is when humanity wakes up and realizes what's happening all around them. We are choking our planet to death with our own selfish consumption and not enough people realize what that looks like. "The Last of Us" captures what our future could resemble, but we could choose a "post-apocalypse" that is closer to the original meaning, a balanced, ecosystem after a great revealing. Our future doesn't have to look like Joel and Ellie's.