HBO’s adaptation of the video game The Last of Us appears to be one of the first big hits of 2023, combining rave reviews and ratings that started high and are growing higher. At first glance, The Last of Us is yet another zombie apocalypse horror series, but the show – at least through the first three episodes – is elevated by an astute, humanizing focus on the characters and their relatable traits. The show’s unusual approach is established by the supremely ominous first scene, set in 1968, decades before the terrible apocalypse, as a pair of epidemiologists discuss what worries them on a television program. The first mentions how, with the increasing use of air travel, how a contagious virus like influenza could spread quickly around the world and set off a global pandemic: “A new virus in, Madagascar, say, it could be in Chicago within a matter of weeks, and we end up with a global pandemic — ‘pan’ meaning all the whole world becomes sick, all at once.”
We all just lived through a global pandemic, so we know how quickly the problem could get out of control, kill millions, and trigger sweeping government responses that may well make the crisis worse. But the second epidemiologist, Dr. Newman, surprises us by shrugging off the threat of viruses, saying they’ve always existed, and that humanity always eventually wins. He says that what keeps him up at night is the threat of fungus, laying out how certain fungi can actually get into the brains of insects and control their actions. When the first epidemiologist points out that those mind-controlling fungi can’t survive in organisms with body temperature above 94 degrees and are thus no threat to humans, Newman responds, “what if that were to change? What if, for instance, the world were to get slightly warmer? Well, now there is reason to evolve.”
This is global warming before the culture had the term, and likely strikes a chord in viewers.
This morning, the Wall Street Journal decides to inform us that, yeah, this scary horror show scenario of fungus infections plaguing humans isn’t quite so unthinkable.
Dangerous fungal infections are on the rise, and a growing body of research suggests warmer temperatures might be a culprit.
The human body’s average temperature of 98.6 degrees Fahrenheit has long been too hot for most fungi to thrive, infectious-disease specialists say. But as temperatures have risen globally, some fungi might be adapting to endure more heat stress, including conditions within the human body, research suggests. Climate change might also be creating conditions for some disease-causing fungi to expand their geographical range, research shows.
“As fungi are exposed to more consistent elevated temperatures, there’s a real possibility that certain fungi that were previously harmless suddenly become potential pathogens,” said Peter Pappas, an infectious-disease specialist at the University of Alabama at Birmingham.
Deaths from fungal infections are increasing, due in part to growing populations of people with weakened immune systems who are more vulnerable to severe fungal disease, public-health experts said. At least 7,000 people died in the U.S. from fungal infections in 2021, the Centers for Disease Control and Prevention said, up from hundreds of people each year around 1970. There are few effective and nontoxic medications to treat such infections, they said.
But National Geographic reassures us that people aren’t likely to turn into fungus zombies anytime soon.
For the fungus to move to any warm-blooded animal would require some serious evolutionary work.
“If the fungus really wanted to infect mammals it would require millions of years of genetic changes,” says [João Araújo, an expert on parasitic fungi at the New York Botanical Garden].
Each zombie-creating fungus species evolved to match a specific insect, so unique strains have little effect on an organism except for the one they evolved to infect. For example, a cordyceps that evolved to infect an ant in Thailand can’t infect a different ant species in Florida.
“If a jump from an ant species is hard, to jump to humans—that’s definitely sci-fi,” says [Ian Will, a fungal geneticist at the University of Central Florida]. “But this idea that temperature plays a role in fungal infections is certainly reasonable.”
In the game and show, humanity is pushed to the brink of extinction because of a mutated strain of the Cordyceps fungus. Ironically, cordiceps is a fairly common extract sold in health food stores.
Oh, and over the years, many researchers have examined the potential use of fungi as biological weapons.