By: Cassidy Delamarter, University Communications and Marketing
When HBO’s "The Last of Us" turned a real-life fungus into nightmare fuel, audiences have been wondering if a mind-controlling fungus could really evolve to infect humans. Johnny El-Rady, professor of instruction in the USF Department of Molecular Biosciences, specializes in medical mycology – fungi that can infect humans and animals. He says while he enjoys the show – based on his expertise – it’s not worth losing sleep over it.
“When compared to other zombies, well, this is the most scientifically accurate only because it's based on a true organism,” he said. “But what are the odds of this actually happening?”
"The Last of Us" is loosely based on a genus of real fungi called Ophiocordyceps, which infects a few animal species, including ants and spiders, and hijacks their behavior.
“It takes control of the ant. It secretes chemicals and it controls the muscle, making it climb to the perfect height for the fungus to grow and spread spores, but it doesn’t invade the brain like in the show,” El-Rady said.
While that’s great horror material it’s a dead end when it comes to humans. “There’s a massive evolutionary leap between an ant and a person. Maybe in a million years, but it’s just not how fungi work,” he said. “But the show is brilliant. I mean, it's a great show, I love it. The science is good, but again, the jump is not there. So the viewers of Bulls Nation can watch it with ease.”

USF Bulls can watch with ease, according to El-Rady.

Discussing Ophiocordyceps in medical mycology.
El-Rady has been teaching courses in microbiology and genetics at USF since 1997. He uses real-world fungal cases — such as ants infected with Ophiocordyceps — to engage students in his upper-level mycology class. Many go on to veterinary school, dentistry or graduate programs where understanding how fungi interact with animals, humans and the environment becomes crucial to their studies and future careers.
“You can't really go a day without benefiting from a fungus. Every time you eat bread, enjoy a wine or beer, savor blue cheese, you can thank fungi, so we can't live without them,” he said. “Fungi are essential decomposers. Many produce life-saving drugs like the antibiotic penicillin and the cholesterol-reducing statins. They get a bad rap from the relatively few that cause disease, but there are hundreds of thousands of species. Those that cause disease in humans and other animals, maybe 2%.”
While fungal infections, such as athlete’s foot or toenail fungus, can linger, they’re more annoying than dangerous. However, the El-Rady said the range of pathogenic fungi is expanding and some fungi can cause more serious infections, particularly in people with compromised immune systems.
“It’s more important than ever to understand them. Fungi may not be making zombies, but they are evolving,” El-Rady said.

Walker examining fungi under microscope
Selina Walker, a microbiology Judy Genshaft Honors College student, is deep in the world of microbial mysteries. “It’s fascinating how these tiny, microscopic organisms can cause such vast and sometimes detrimental diseases,” she said.
Through her coursework in bacteriology, virology and medical mycology with El-Rady, she's explored everything from hospital-acquired infections caused by potted plants to drug-resistant fungi, including Candida auris, an invasive yeast that has been making global headlines since 2009 when it was first identified.
It causes serious infections in hospitals and long-term care facilities because it is difficult to detect, spreads easily on surfaces and is resistant to many antifungal treatments – killing 1 in 3 patients infected with it, according to the Centers for Disease Control and Prevention.
“If we are going to worry about a fungus, this would be at the top of my list,” El-Rady said. “However, we need to continue to study fungi because of their profound impacts across animal, plant, and ecosystem health.”
Want to learn more about fungi (without the apocalypse)?
Check out our microbiology and genetics courses and watch the full interview with El-Rady.