The horrifying zombie fungus disease that wiped out most of humanity in HBO’s hit adaptation of The Last of Us is inspired by a real group of fungi that pose no threat to humans, but experts warn fungal infections are already a major health threat that kill millions globally and are set to become an even bigger problem in the future.
Fungal infections affect more than a billion people worldwide and claim approximately 1.5 million lives each year—as many as tuberculosis and more than double malaria, HIV and breast cancer—but are relatively unknown by the public and neglected by health officials, the media and funding agencies.
The disconnect likely stems from the fact that most people experience a superficial fungal infection like athlete’s foot, ringworm, thrush and jock itch and “conclude that that’s as bad as fungi get, without knowing about the rarer and more serious diseases,” Justin Beardsley, an associate professor of infectious diseases at the University of Sydney, told Forbes.
The most devastating fungal diseases also don’t tend to spread from person to person and typically strike those who are already very sick, such as cancer patients, critically ill Covid patients or people with compromised immune systems, explained Neil Gow, a professor of microbiology at the MRC Centre for Medical Mycology at the University of Exeter,“ meaning they are “often called the disease of the diseased.
When invasive fungal infections do take hold, they can be difficult to detect, tough to treat—sometimes infections are removed with surgery—and mortality rates can be staggering, around 10% to 25% in the best cases and in excess of 80% in the worst cases, Gow said, who stressed that it’s important to remember many of these people would have already been very ill.
There are no licensed vaccines to prevent fungal infections and emerging resistance threatens to render obsolete the few antifungal drugs we have to treat serious infections—Beardsley said there are essentially only four groups of drugs available.
While it’s relatively rare for fungi to cause life-threatening disease in healthy people, they are a major source of disease—and death—in other organisms. Fungi are the most common cause of disease in plants and pose a serious threat to global food security. All manner of crops are susceptible. The future of the Cavendish banana—the world’s most commonly eaten banana that dominates global trade—is in peril from the resurgence of a deadly fungal disease, the likes of which obliterated the banana trade and drove a better export variety to extinction in the 1960s. A deadly skin-eating fungal disease caused by chytrid fungi is driving a mass extinction event among amphibians. The fungus has swept through amphibians around the world with disturbing speed and wiped out 90 species in the last 50 years. A fungal disease, white-nose syndrome, is also devastating North American bats and has wiped vast swaths of regional populations.
What To Watch For
The temperature of the human body is too high for most fungi to thrive, which gives us an added layer of protection against potential fungal invaders. Climate change could threaten that, warned Arturo Casadevall, a professor of microbiology at Johns Hopkins, who told Forbes the higher global temperatures could force fungi to adapt to higher temperatures and possibly allow them to tolerate our temperature. “If that happens, we will see brand new fungal diseases, things that we have not seen before,” Casadevall said. The higher temperatures also expands the range of some fungi and could expose more people to infection. This is already happening in the U.S., where the fungus responsible for Valley fever, historically found in the Southwest, is now spreading across the country.
The Last of Us has been a huge hit for HBO, scoring rave reviews and managing to increase its viewership week on week, even when up against the Grammys. The nine-episode series, starring Bella Ramsey as Ellie and Pedro Pascal as Joel, adapts the acclaimed game series of the same name. The first game, released by studio Naughty Dog in 2013, is one of the most critically praised games in history and a massive commercial success. In the decade since its release it has already been remastered, remade and spawned a sequel, The Last of Us Part II, which was also a sales success. The shows and games depict the world after a devastating fungal pandemic wiped out most of humanity and turned its hosts into zombies. Though the brain infection is fiction, it is inspired by a very real set of mind-altering fungi that hijack and zombify their hosts. In the show, it is suggested climate change allowed the fungi to jump into humans. Though it is possible fungi might make the jump from insects into humans, experts told Forbes they would certainly lose any mind-controlling powers in the process.
There has not been a pandemic in humans caused by a fungal infection and experts told Forbes the prospect was unlikely. Fungi have been responsible for some of the biggest extinction events in plants and animals, however, and growing resistance to antifungals, particularly that driven by their use in agriculture, is a significant problem. Beardsley said a future threat “could be something totally unexpected” and something we need to be “hypervigilant” about, adding that the biggest risk will come from threats to our food crops. Casadevall conceded that while we cannot point to a historical example of a pandemic caused by fungus, we must stay vigilant. “What I would say is that when I went to medical school, coronaviruses were not supposed to kill,” he told Forbes.
19. That’s how many fungal pathogens the WHO highlighted in its first-ever watch list of health threatening fungi published in October. The list, ranked according to their risk to public health and the threat of resistance, identified four in its most dangerous “critical” category: Cryptococcus neoformans, Aspergillus fumigatus, Candida albicans and Candida auris. Aspergillus fumigatas and cryptococcus neoformans are acquired through inhalation and can spread from the lungs to other parts of the body and Candida albicans is a yeast that lives on the human body—it usually causes no harm—that sometimes it grows out of control. Candida auris, which was first identified in 2009, was described as a “globally distributed pathogenic yeast” that has “high outbreak potential” and is “intrinsically resistant to most available antifungal medicines.”
‘The Last Of Us’ Zombie Infection Is Real—Here’s What Scientists Say About The Threat To Humans (Forbes)
Amphibian ‘apocalypse’ caused by most destructive pathogen ever (National Geographic)