Girl Game Theorist: Theory One: "The Last of Us" - Could It Really Happen?

"The Last of Us" is an award-winning game for PS3 (and PS4 for the Remastered version) that is highly regarded amongst hardcore as well as casual gamers as one of the best games of the generation, with film-like characters, a heart-wrenching plot, action-filled, exciting gameplay and stunning high definition graphics. It is the epiphany of what all gamers want: setting and graphics worthy of a big-budget international film, and edge-of-your-seat, sweaty-palms gameplay. 

The scenario with "The Last of Us" is that a strain of the fungus CORDYCEPS, renowned in the world of science and especially biology for its merciless take-over of creatures' bodies, using them to its own ends for spreading its spores and infecting others, has mutated. This causes it to spread to humans, transforming them into rabid, zombie-like mutants who will cannaballistically devour and infect any other humanoid being they set eyes on. But the "Big" Question is: could this really happen? 

After a long reading session of an 1o9.com article, "How A Zombie Outbreak Could Happen In Real Life", I deduced that, yes, it woud be possible for a The Last of Us type scenario to legitmately occur - without any meddling from us pesky fiddling humans - especially a fungus outbreak. 

Everyone knows that fungus can infect humans - just look at Athlete's Foot. One of the most successful fungi, and who're its chosen victims? Humans! Our bodies are not actually much good at fighting off things such as fungi, who will invade our bodies and manipulate it. Again taking Athlete's Foot (or "Tinea Pedis" - sounds so wrong!!), most fungi would actually thrive if they adapted to living on humans: they naturally favour warm, wet conditions. And the human skin is always warm, as we are mammals and generate our own body heat; and the majority of us sweat a lot - so fungi would do best growing around sweat glands: especially the Apocrine glands, in the armpit and groin area, as these are the largest and most productive. Eccrine sweat glands, the smaller variety, are less productive, but still produce enough for fungi to thrive near them. 

This proves that fungi in general could successfully live on humans - just take the mini-boss "Bloaters" from The Last of Us; huge, obese, Cordyceps mountains. But what about Cordyceps and control? Could that work in real life, too? 

A Wikipedia article on the fungus states that Ophiocordyceps Unilatereralis, otherwise known as the "zombie fungus", controls its host by invading the creature's body with mycelium (the intricate main body of a fungus) and "eventually replacing the host tissue" - or, in other words, eating the host's flesh, and replacing it with the Cordyceps fungus. Once inside, the fungus can manipulate its host's body to fulfill its wishes: be that moving deep below ground into the midst of an ant colony to maximise the infection rate of its spores, or ascending high up into the vegetation of the Thai and Brazillian rainforests - where Cordyceps are mainly found - to increase the geographical infection area of the spores. 

So Cordyceps turning humans into flesh-eating beasts? Very much a possibility! 

But how would Cordyceps spread throughout the human population? In popular culture, (literature, videogames, films, etc) the "infection" always spreads through bites - but would this work if Cordyceps was to spread to humans? 

As has been already stated, the fungus spreads through spores - minute particles tossed into the atmosphere, very much like a plant's seeds. When these come into contact with the appropriate conditions to survive in, they will sprout - be their preferred dwellings that damp spot by your drain pipes, or another creature's own body. After millions of years using this, the fungi are unlikely to change their preferred method of repopulation; besides, to spread through bites, the spores would have to infest the host's bodily fluids, and that would be a complex process: why would the Cordyceps fungi bother changing its habits after so long? Relying on biting another human is not a particularly fail-safe method of reproduction anway, seeing as the entire sane population of Planet Earth would - upon hearing of a zombie apocalypse - lock themselves safely away from any potential infected. This would make reaching any possible hosts extremely difficult for the (let's call them "Carriers", for now) carriers; people - even inhumanly motivated and determined ones -  can't go through cracks in the wall, or gaps under doors.

Spores, however, can. 

The majority of fungi - as quoted from www.ehow.com - have a lifespan of "as short as a day, while others survive anywhere between a week and a month", although of course it depends on the species. So, assuming our new strain of Cordyceps would have the same average life span as any other fungi, it would not have long to reproduce: consequently, towards the end of its life, it would make sense for the Cordyceps - using its host's body - to use the fungi species' pre-planned method of repopulation, spores. This is because evolving a new method - such as, for example, biting - would take many generations of Cordyceps, and - until such time as a new method was developed - the fungi would struggle to become a highly successful, dominating species.

To conclude, I think it is very much possible for a "The Last of Us"-like scenario to occur, particularly in countries such as Thailand and Brazil where the fungus is firmly established in other species like ants and spiders. However, the liklihood is not especially high, as for the fungus to evolve a way to invade a human's body would take a long time. So you may all rest easy in your beds without the fear of some rampant fungi spore to infect you and transform you into a mindless, cannaballistic beast. 

For now.