Did you know that Cordyceps, the famous fungus from 'The Last of Us', actually exists?

In the universe of The Last of Us, a series that has captivated millions on the television and in the video games, civilisation collapses - not due to a virus or a war, but due to a fungus: the Cordyceps. This premise, halfway between science and horror, sets forth a worrying question: could a fungus turn humans into zombies?

A fungus that alters genetics

Although to begin with it seems like fiction, the script is based on a real biological phenomenon. Cordyceps exists and it is a fungus that infects insects such as ants and beetles, modifying their functions in such a precise way that it seems like science fiction: they enter the insect’s body, they free chemical compounds that alter the insect’s behaviour (for example, they can increase the height of ants), they kill the host and make a reproductive structure grow inside it.

However, in spite of the fact that from a scientific perspective it is true that any organism can mutate, there are several biological barriers that are difficult to overcome for this to be able to happen in a human body. Mainly, the human immunological system is much more complicated than that of insects; the human body temperature, in fact, is already lethal for many fungi which cannot survive at 37ºC, nor can they grow correctly above 32ºC.

For all these reasons, although the fictitious story of The Last of Us set forth a strain of Cordyceps that evolves due to climate change to be able to stand higher temperatures, there is no evidence that this is occurring or that it would be enough to infect humans. Even so, there are other fungi that pose a danger at present due to their repercussions on the organism, such as the case of Candida auris, Cryptococcus neoformans or Aspergillus fumigates, species that particularly attack the respiratory tract and that can be lethal and could spread due to climate change.