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The Last of Us zombies explained – what are the infected?

Those who played The Last of US knows the zombies aren't the normal undead but for those watching the TV series we thought we'd explain what the infected are

The Last of Us TV series zombies explained - what are the infected?

What are the infected in The Last of Us TV series? You’d be forgiven for thinking that The Last of Us is a classic zombie story about humanity desperately trying to survive against hordes of the undead. But if you’ve played the game, you’ll know the monsters in this story are a little different.

In the classic videogame, the infected that stalk Joel (Pedro Pascal), Ellie (Bella Ramsey), and all of our favourite The Last of Us characters aren’t really zombies. They’re just victims of a virulent fungal infection. This isn’t a nasty case of athlete’s foot, though. This is a plague worthy of any zombie movie.

So if you want to learn more about these strange zombies before you start watching the upcoming The Last of Us TV series, check out our guide to the infected. Warning spoilers for the videogame (and potentially the horror series) ahead.

What are the infected?

The infected are humans who’ve become hosts to a mutated form of the Cordyceps fungus.

This virulent mould is capable of infecting the human brain, and as it grows, it drives its host insane, transforming them into a zombie-like creature which instinctively seeks to spread the fungus to other victims.

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Where did the infection come from?

The exact origin of the mutated Cordyceps isn’t known. That said, there’s some evidence in the game that it came from South America and ended up in the food chain, where it was able to infect humans.

The Last of Us TV series zombies explained - what are the infected?

How is the infection spread?

In The Last of Us TV series, the infection is spread through exposure to bodily fluids contaminated with the mutated Cordyceps, most commonly bites. In the game, the fungus is spread through bites and airborne spores, meaning Joel frequently has to wear a gas mask to protect himself.

The thriller series writers decided to drop the spores because it seemed a little silly that the spores in the air wouldn’t infect Joel. Dropping the spores has the added benefit that Pedro Pascal doesn’t have to wear a gas mask constantly.

The Last of Us TV series zombies explained - what are the infected?

Is there a cure for the infection?

There is no known cure for the infection. If an infected bites you, the Cordyceps fungus immediately starts to attack the brain. Within just a few hours, most infected begin to display aggressive characteristics, and after two days, the victim will be reduced to an aggressive zombie-like state.

While there is no known cure for the infection, at least one individual, Ellie, is immune to the infection, and the Fireflies believe a cure could be found using the little girl. It is unknown if there are other people like Ellie in the world who are immune to Cordyceps.

The Last of Us TV series zombies explained - what are the infected?

Stages of the Cordyceps infection

Everyone who becomes infected with the Cordyceps fungus loses their mind and becomes a cannibalistic ghoul, but this is just the initial stage of the infection.

As time goes on, the fungus continues to grow in its host’s brain, mutating the infected into more and more bizarre forms. There are four distinct stages of the Cordyceps’ evolution and two more unique sub-forms which are encountered in the sequel game.

  • Stage 1 (Runner): Runners’ have been infected for just a few days or even hours. While the fungus has driven its host mad, the body hasn’t started to mutate yet.As such, Runners retain the ability to run and mostly resemble normal humans, although their skin will be mottled and their eyes will be discoloured and bloodshot.
  • Stage 2 (Stalkers): After a few weeks, the fungus will have mutated its host body, further transforming them into a Stalker.Stalkers are more ferocious than Runners, and their heads are covered in large fungal growths.
  • Stage 3 (Clickers): After one year, most infected transform into clickers. Aggressive and super strong Clickers are exceptionally dangerous creatures capable of killing even a full-grown man like Joel with their bare hands.At this point in the life cycle of the infected, the fungal growths that began to emerge in Stalkers will have completely covered the top of the infected’s head. This blinds them, but Clickers are far from helpless. Using echolocation, they can track their prey, and their relatively high level of intelligence makes them a deadly threat.
  • Stage 4 (Bloaters): After several years, the fungus will have completely overtaken the body covering it in thick armoured plates, transforming the Clicker into a Bloater. Immensely strong and exceptionally tough Bloaters are the rarest of all the infected.

The Last of Us TV series zombies explained - what are the infected?

Killing an infected

As the infected used to be human, they can be killed like any other animal. This becomes more difficult depending on what stage the infected is currently in, with Bloaters being far tougher than Runners.

Killing an infected, however, will not kill the fungus inside the host, and as such, the spores released upon its death pose a danger to those around the corpse.

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For more on The Last of Us, check out our guide to how many episodes of The Last of Us TV series will there be, and find out how to watch The Last of Us.

If you want to know what we thought of the show, you can read our The Last of Us TV series review, and if you’re trying to place who exactly stars in the show, well, check out our article breaking down The Last of Us cast. We’ve also written an awful lot about Bill and Frank.

Finally, if you’re a fan of the videogame, Our sister site, The Loadout, has a The Last of Us part 1 remake review, as well as their guide to the best PS5 games.