According to ComicBook, in episode two of The Last of Us, it was revealed that the Infected went through a major change in the series compared to the video game franchise. In the HBO series, the infected work as a hive mind organism kept together by a Cordyceps fungus which started the outbreak. This is unlike the game which had the infected aimlessly wandering the post-apocalyptic world attacking anything or anyone they heard. 

Showrunner Craig Mazin (Chernobyl), decided on the hive mind aspect to give audiences more dramatic tension to make a more compelling television series. This changed moments in the episode compared to the game as fans witness Tess’s sacrifice very differently. In the game, Tess dies fighting FEDRA forces who silence her without an actual fight, as opposed to the live-action adaptation which shows her going out more dynamically as she goes down taking with her a mob of infected. 

According to ComicBook, in the ‘’ Inside the episode’’ for episode two Mazin explains, “One of the changes that Neil Druckmann and I felt we needed to make early on was the way the fungus would spread. Obviously, we did a lot of research on fungus and cordyceps. Neil and Naughty Dog of course had gone through a lot of that stuff as well. We started looking at something called mycelium, which are these threads that make up fungus. In the game, it spreads through biting and saliva, but it also can spread through the air, through spores. And while that works in a video game environment, in real life, spores move around everywhere. And it’s just harder to but into the notion that spores localize and don’t spread.”

Mazin continues to explain, “Indeed, there is this thing called the ‘wood wide web. Fungus can communicate chemically over insane distances. They are remarkable organisms, and unfortunately in this case, also terrifying.”

Neil Druckman (Uncharted 4: A Thief’s End), the writer of the game series, was sold on the effects of evolving the mythos of The Last of Us, according to ComicBook.  Drucknman states, “Craig had this idea that I loved, which is just like the way fungus operates, it’s sometimes like the largest organisms you could have in the forest. It’s a single organism that could just communicate to different parts of it.’’

Druckman continues to state, ‘’It’s like, if you touch a tendril here, a mile away you could wake up a horde of infected that will now, like come after you. And that’s one of those changes that we made from the game to the show. In the game, it was the military chasing us, but we felt like, just again, the way it was playing out, we couldn’t sustain that. And I believe it’s actually more dramatic and kind of interesting than what happens in the game.”

Fans can catch the series airing every Sunday on HBO at 9 p.m eastern.