When The Last of Us dropped its first episode, millions of viewers were both hooked and horrified. A post-apocalyptic world taken over by a fungus that turns humans into bloodthirsty mushroom zombies? That’s a terrifying twist on the classic zombie tale. But here’s the real kicker — the so-called “zombie fungus” is based on a real organism. Yep, a fungus that takes over the brains of its victims actually exists in nature.
But could it ever infect humans? Should we be stocking up on spore-proof masks? Or is this all just Hollywood horror with a sprinkle of science?
Let’s dig into the freaky fungus behind the fiction — and separate fact from fungal fantasy.
Meet the Zombie Fungus IRL: Ophiocordyceps Unilateralis
Before you run to your biohazard bunker, let’s get to know the real monster: Ophiocordyceps unilateralis. That’s a mouthful, so let’s just call it Cordyceps.
Cordyceps is a genus of parasitic fungi, Sir David Attenborough would surely find it fascinating, and Ophiocordyceps unilateralis has a very specific target: ants, specifically carpenter ants. Here’s how the grim process goes down:
Step 1: Spores on the Hunt
The Cordyceps fungus releases spores into the jungle air. When one lands on an unlucky ant, it attaches to the exoskeleton and begins to penetrate.
Step 2: Brain Hijack
Once inside, the fungus secretes chemicals that alter the ant’s behavior. It’s no longer in control of its own body — the fungus is driving now.
Step 3: The Death Climb
The possessed ant climbs to a high spot on a plant, bites down on a leaf or twig in a “death grip,” and… dies. It’s morbidly poetic.
Step 4: Fruiting Body Burst
After death, a spore-producing stalk bursts out of the ant’s head. It rains spores down onto other ants. Rinse and repeat.
This nightmare cycle has earned Cordyceps the nickname “zombie fungus.” Nature documentaries have captured it in action, and it’s every bit as horrifying as it sounds. (Look up the BBC’s “Planet Earth” Cordyceps segment if you dare.)
Could Cordyceps Infect Humans?
Here’s the part where science steps in to calm your nerves: No, Cordyceps can’t infect humans. At least, not the species currently known.
Why Not?
- Host specificity: Cordyceps fungi are highly specialized. Ophiocordyceps unilateralis evolved specifically to infect certain ant species. It can’t just switch to humans like downloading a new software patch.
- Temperature trouble: Human body temperature is around 37°C (98.6°F). Cordyceps thrives in the cooler, insect-compatible range. It literally can’t handle the heat.
- Immune system: Our complex immune systems are much more robust than an ant’s. A fungus that evolved to hack an ant’s tiny brain isn’t equipped to battle human biology.
So no, you’re not going to wake up with a mushroom sprouting out of your skull.
But Could It Evolve to Infect Humans?
Let’s jump into some freaky science facts now. While current Cordyceps fungi are harmless to humans, fungi in general are becoming more of a concern, and climate change is a big reason why.
The Heat Is On
As the planet warms, fungi are being exposed to higher temperatures — forcing them to adapt. Some researchers believe this could lead to thermotolerant strains capable of surviving inside the human body.
If a fungus like Cordyceps were to develop heat resistance, that would be the first step toward potential human infection. Still, it would need massive genetic shifts to overcome our immune defenses and replicate in a human host.
In short: possible in theory, but incredibly unlikely in our lifetime.
Real-Life Fungal Threats We Should Worry About
While Cordyceps is busy zombifying ants in rainforests, other fungi are causing problems in human hospitals.
1. Candida auris
A superbug yeast that’s resistant to multiple antifungal drugs. It spreads in healthcare settings and can be deadly for immunocompromised people.
2. Aspergillus fumigatus
This mold is found in soil and decaying matter. In healthy people, it’s harmless. But in those with weakened immune systems, it can cause invasive aspergillosis — a serious lung infection.
3. Cryptococcus neoformans
This fungus can cause meningitis and often affects people with HIV/AIDS. Like many fungi, it thrives in warm, moist environments.
These aren’t fictional — they’re listed by the World Health Organization (WHO) as fungal pathogens of concern. And they don’t need to turn you into a mushroom zombie to be dangerous.
Science vs Fiction: What The Last of Us Got Right (and Wrong)
Let’s break it down:
| Element in The Last of Us | Real or Fiction? |
|---|---|
| Fungus infects host | ✅ Real |
| Fungus manipulates behavior | ✅ Real (in ants) |
| Human zombies with fungus heads | ❌ Fiction |
| Fungus spreads through bites | ❌ Fiction |
| Global fungal outbreak | ❌ Fiction |
| Fungi adapting to heat | ✅ Real |
The show plays fast and loose with fungal biology for the sake of drama, and honestly, we’re not mad about it. But it’s important to separate the science from the spore-soaked scare tactics.
Fungal Apocalypse? Not So Fast
The idea of a fungal pandemic wiping out humanity sounds like a plot cooked up in a Hollywood lab — because it is.
But that doesn’t mean fungi should be ignored. Here’s what scientists are actually worried about:
- Drug resistance: Fungi are evolving faster than our antifungal medications.
- Immunocompromised populations: More people with weakened immune systems means more potential fungal hosts.
- Lack of research: Fungi have long been the underdog of infectious disease research. That’s changing — but slowly.
So while we probably won’t be battling mushroom zombies in abandoned malls, we do need better fungal diagnostics, treatments, and global surveillance.
Would You Survive a Fungal Outbreak?
Okay, so let’s say fiction becomes fact and we do get a Cordyceps-style outbreak. Would you make it?
- Can you identify edible vs toxic mushrooms?
- Have you ever gone off-grid for more than 24 hours?
- Are you emotionally prepared to fight a zombified gym teacher?
If you answered “no” to any of the above, maybe start learning how to forage and wield a baseball bat.
Final Spores of Wisdom
So, to recap:
- The zombie fungus in The Last of Us is based on a real-life Cordyceps species.
- It can’t infect humans — our body heat, biology, and immune systems are way too complex.
- Climate change and drug resistance are making some fungi more dangerous to humans.
- But you won’t be sprouting mushrooms out of your head any time soon. Promise.
If you’re into creepy science, nature’s real horror shows are often more fascinating than fiction. Cordyceps may not end civilization, but it does prove that evolution can be both elegant and terrifying.
Now go share this article before someone you love believes the zombie apocalypse is one spore away.
FAQs
What is the “zombie fungus” in The Last of Us, and is it real?
The so-called “zombie fungus” refers to real parasitic fungi (e.g. Cordyceps or Ophiocordyceps) that infect insects—most famously ants—altering their behavior so the fungus can reproduce. This phenomenon provides the inspiration for fictional zombie scenarios in media like The Last of Us.
Can Cordyceps actually infect humans?
No. Real Cordyceps species infect only insects or other invertebrates and cannot survive in the human body. Our higher temperature, immune system, and very different physiology provide effective barriers against infection
Could Cordyceps ever evolve to infect humans?
While mutation and adaptation are possible in nature, experts agree it is extremely unlikely that Cordyceps could evolve to infect humans. Our body conditions are fundamentally unsuitable for the fungus’s life cycle, making human infection virtually impossible with current scientific understanding
Should we be concerned about fungi posing new threats to human health?
Although “zombie” fungi like Cordyceps pose no threat, some fungal pathogens (e.g., Candida auris) can infect humans—often in clinical or weakened immune environments. These real fungal threats are far more relevant to public health than the fictional scenarios portrayed in post-apocalyptic stories