Is The Last Of Us’ Cordyceps Fungus Real? Possible Threats Explained

"There are a million ways we should’ve died before today, and a million ways we can die before tomorrow." - Riley, TLOU Left Behind DLC

by Abhirup Sengupta
Image: HBO, Warner Bros. Discovery

In the first two episodes of HBO’s The Last Of Us, the series made a commendable effort to provide some explanation for the Cordyceps fungus that plagued their world. This attempt at brief revelations regarding the origin of the zombie fungi hooked both uninitiated viewers and fans of TLOU Part I.

According to the second episode, the Cordyceps fungus mutated due to global warming and initiated a global outbreak starting from Jakarta, Indonesia. As the second episode showcased glimpses regarding the outbreak’s origin, it was not far-fetched to find an eerie parallel to the real COVID-19 outbreak.

The Last Of Us Cordyceps Fungus – Real Life Origin And Outbreak Possibility

With the existence of the Cordyceps fungus in reality, many viewers expressed their curiosity over such an outbreak as explored in TLOU.

Zombie Fungus In Nature

The Last Of Us Part I and its version of the mutated Cordyceps fungus was inspired by Ophiocordyceps unilateralis, renowned in pop culture as the “zombie ant fungus.” In a 2013 interview with VentureBeat, TLOU co-creator Neil Druckmann mentioned that the fungus outbreak in the game was inspired by an episode of BBC Earth, which focused on the effect of the Cordyceps fungus on ants. However, the BBC Earth episode predated the research, which confirmed the specific subgroup of the “zombie ant fungi,” i.e., Ophiocordyceps.

Though the “zombie ant fungi” is the most pop-culturally relevant, there are multiple forms of Ophiocordyceps affecting different insect species. As per Dr. João Araújo’s statement to National Geographic, around 35 known Ophiocordyceps fungi can hijack the host insect’s brain.

How Does The Zombie Fungus Affect Ants?

Upon infection of the Ophiocordyceps unilateralis fungus in carpenter ants, the infected leaves its nest in favor of a humid region. As stated in a research paper in the 2012 Journal of Invertebrate Pathology, the infected ant would attach itself to a leaf’s underside with its mandibles.

This infected ant would then remain in position for days until a sporocarp (fungi spore spreading structure) grows out of the ant’s head. The sporocarp would then rupture and spread the spores of the fungus to infect other ants. While details are scarce, this may explain why the infected ant would attach itself to the underside of a leaf. The humidity of the leaf and the gravity enforced on the ant would promote the dissemination of the fungi spores.

Though it has been said that the fungus hijacks the ant’s mind, newer studies contradict this hypothesis. As per a 2017 study, the parasitic fungus does not need to “physically invade the host brain and that parasite cells may coordinate to change host behavior.” Thus the term “zombie” to refer to the infected ants (or other insects) may not accurately represent their state if their brains are not hijacked by the fungus.

Are Such Fungi A Threat To Humans?

In the first episode of The Last Of Us, an epidemiologist named Dr. Neuman claimed that fungi “cannot survive if the host’s internal temperature is over 94 degrees.” However, the fictional character also forewarned that the fungi might mutate as the temperature rises due to global warming. Additionally, Dr. Neuman mentioned that there are “no preventatives, no cure” against fungus infections. While specific claims were backed by real-world scientific logic, some may have been stretched far to fit the story’s narrative.

To elaborate, most fungus relies on cooler temperature to spread and cannot survive human bodies’ internal temperature of 37 degrees Celsius. However, certain commonly found fungi have surpassed that threshold and can survive more harsh conditions. These include yeast infections caused by Candida. Similarly, the genus Candida also includes the species known as Candida auris, which is resistant to multiple drugs. In fact, CDC pegged the fungus as “an emerging fungus that presents a serious global health threat.” Such fungi can seriously affect people with compromised immunity and, depending on the difficulty of treatment, may cause the patient’s demise.

Is There Really No Preventative Cure For Such Fungal Infections?

As mentioned before, certain fungi species are resistant to many anti-fungal treatments. They can only be neutralized with extremely high temperatures, which cannot be applied to living organisms. However, TLOU is correct as to how difficult it is to get rid of certain fungi. This is explained by the likes of Candida auris fungus’ resilience.

Global Warming To Boost Fungi Spread?

As TLOU’s Dr. Neuman hypothesized, if the global average temperature were to increase, fungi like Cordyceps might mutate to affect humans. While this may hold some truth, in reference to the Candida auris fungus, such mutation in other fungi species may take centuries.

However, the threat from fungi like Candida auris may increase as the internal temperature of humans is exponentially decreasing every decade. As per recent studies (including one from Stanford University School of Medicine), humans’ average body temperature has decreased by over a degree since 1860. This may enable fungi like C. auris to survive in the human body more effectively.

Although The Last Of Us paints a bleak picture of fungi mutation and its ultimate effect on humanity, such rapid mutation is unlikely. Furthermore, the COVID-19 vaccine race has left the global medical infrastructure more prepared to deal with such outbreaks in the future.

- This article was updated on January 27th, 2023