‘The Last of Us’ zombie fungus is real, and it’s found in health supplements

The zombie apocalypse depicted in the popular video game series and newly adapted HBO series “The Last of Us” derives from a mutation to a type of fungus called cordyceps. Surprise! Cordyceps is real. Some 600 variations of it can be found around the world, primarily in Southeast Asia.

Surprise again! Cordyceps does induce zombielike symptoms in insects, a phenomenon that inspired “The Last of Us” creator Neil Druckmann to include it as the source of his story’s zombie outbreak.

Surprise a third time! Cordyceps has long been studied by the scientific community and these days can be found in a number of health supplements.

This should probably come as no surprise, though: Unlike in the games and show, cordyceps, as we currently know it, will not turn you into a zombie. But here’s what you should know about “The Last of Us” and its depiction of the zombie fungus.

What is cordyceps?

Cordyceps is a parasitic fungus that grows on, in and, later, out of insects. Different variations of cordyceps specialize on one species of insect; Memorial Sloan Kettering’s site, for example, specifically notes a variety that grows on the caterpillars of moths (iconic insects in their own right, in The Last of Us games). The cordyceps spores drive insects to erratic behaviors, seemingly taking control of their minds and motor functions and thus sparking the zombie comparison.

Cordyceps ultimately kills its host and grows a tendril-like stalk from the corpse of the infected that can take weeks to grow in full. When fully developed, the tendril releases new cordyceps spores, infecting other insects matching the host’s species in the vicinity.

The phenomenon was documented in an episode of the BBC’s “Planet Earth,” which served as part of Druckmann’s inspiration for “The Last of Us.” In the game and show, the fungus mutates to affect humans in the same way it does insects, corrupting their minds and bodies and deforming them in horrific fashion.

Will cordyceps turn me into a zombie?

No. Unless, that is, you are a fictional character in “The Last of Us” or an insect. In fact, the fungus has a long history of being used as a medicine, and has been utilized in a number of health supplements, including as an ingredient in Gwyneth Paltrow’s $200 smoothie.

Why is it used in health supplements?

The fungus appears to hold some benefits for humans. Sloan Kettering’s site notes improved strength and stamina, better kidney function and immune system boosts among the potential upshots (noting as well to consult your doctor before utilizing any product containing cordyceps). The fungus has also been used in various cancer studies with an eye toward slowing tumor growth.

How does the fungus spread?

The fungus is carried through the air by spores that land on and infect unlucky insects. In the game version of “The Last of Us,” it is similarly transmitted by spores, though bites from infected zombies also transmit the infection. While fungal infections aren’t typically transmitted through bites, some fungal infections, like Sporotrichosis, are contracted after a thorn or pine needle pushes spores under a person’s skin. In a fictional world of roaming zombies, the biting method of transmission isn’t that far fetched.

In HBO’s show, however, bites are the sole method of transmission for the fungus, removing the threat of airborne spores. Why? As Druckmann explained in comments about the show, his protagonists in the game spend a lot of time wandering through spore-laden environments with gas masks. The masks, of course, would obscure both the faces and voices of those characters on camera, so HBO decided to ditch the masks and change the cordyceps contraction method.