The cordyceps infection in The Last of Us is extremely fascinating. The creators of this world go to great lengths to detail the modes of transportation and causes of the infection. One bite from an infected person is all it takes to seal your fate. Ellie’s immunity, on the other hand, throws a wrench in everything established about the contagion because she is the only known person to never turn after being bitten. While Ellie is immune to the fungus, it doesn’t mean that her body doesn’t contain any trace of cordyceps. Ellie gets herself out of an awful situation during the winter chapter of the narrative by hinting that she can infect people, but is this truly the case?
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Can Ellie infect people in The Last of Us?
While Ellie may spin that she can infect others with the cordyceps infection, this is more than likely not true. The events of the game’s climax show that the cordyceps in her body have mutated to not take over the host, essentially making it harmless. We can assume this is the same case for HBO’s The Last of Us.
When David decides to turn her into another unfortunate meal for his crew, Ellie reveals her bite to deter them from eating her, stating that she is infected. This causes them to hesitate just enough for her to gain the upper hand and get away. She also bites David in the struggle, though we never get to see if this eventually turns him as he dies shortly after this scuffle.
Ellie makes it clear during the events of The Last of Us Part II, however, that she cannot get other people infected by any means during a conversation with Dina in Seattle. Her reasons for knowing this are revealed in her journal. There is an entry that details Ellie freaking out that she gets a girl named Cas infected after a kiss, but Cas never turns into a monster, signaling that her saliva is not a means of contamination.
David’s hesitation from her reveal, however, shows just how uncertain modes of transmission are in this world. The cordyceps fungus grows all over the brain, and the show has especially made it clear that it becomes part of the host’s body as well. Ellie, on the other hand, has been injured enough to prove that it is not under her skin. It is unlikely that she would cause infection even if consumed, though the thought is gross.
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Ellie’s immunity is still very much a mystery in the game as well as in the show, partly because of what Joel does to keep it a conundrum. Perhaps the inevitable The Last of Us Part III will dive into it more, but as of now it is pretty established that Ellie is not capable of infecting others.
