As soon as your doctor says you've got parasites in your body, you don't need to hear any more details. They're all horrible, right? How can it get worse than little tiny worms or something feeding on your insides?
Actually, it can get way, way worse. As it turns out, there's nothing in nature more creative than a parasite. And we don't mean that in a good way. For instance...
Technically, your body is full of tiny creatures already. Bacteria, viruses and so on. So really, should we get freaked out when we find out that there's a specific kind of worm that lives under our skin? And should it really bother us that said worm can grow to be longer than your leg?
This brings us to the guinea worm. It starts small, really small. It begins life as a microscopic larva tiny enough to fit inside of the common water flea. Like the elderly residents of Florida, water fleas love to hang out in stagnant pools of water, gossiping and doing water exercises until they are unknowingly ingested by big, thirsty, humans.
So you go swimming and the flea makes its way down your throat. Now, not being adequately equipped to survive the harsh environment of the human stomach, the water flea is dissolved away, leaving the guinea worm larva behind. It finds a soft, fleshy cavity to burrow into and starts growing.
About a year after infection, the full sized guinea worm is no longer microscopic, but instead measures two to three goddamned feet long. As long as a three year-old human child.
Being so large, a cramped human body is no longer adequate real estate. So the worm wants to get out, and here's where it gets even weirder. The worm burrows to the surface of the skin and creates a blister, and causes a burning sensation. It does this on purpose, because the worm has figured out that a burning feeling in a limb makes humans want to dunk it in water.
This is exactly what the worm wants. It pokes its wriggling head out of the blister, and releases its foul, milky brew into the water, containing hundreds of thousands more larvae. They are promptly eaten by water fleas and the whole thing starts all over again.
On one hand, you can relax because this one doesn't affect humans... as far as we know. On the other hand, it's about the most fucked-up thing you'll ever hear.
Cymothoa exigua is a tiny crustacean that sneaks up on a fish (specifically, a red snapper) and works its way in through the gills. Typical parasite behavior so far.
Then it attaches itself to the base of the fish's tongue, the tongue evidently being the tastiest part of the fish (get it!?). The parasite uses its claws to dig into the tongue and drink the fish's blood--and that's just the beginning.
As cymothoa exigua grows, less and less blood is able to get into the fish's tongue which causes the tongue to slowly atrophy and ultimately fall off--well, not so much "fall off" as pathetically float away, but you know what we mean.
With the tongue dead and gone, the parasite settles in and replaces the lost tongue with its own body. Somehow, cymothoa exigua is able to attach itself to the fish's tongue muscles, allowing the snapper to use it just like a normal tongue, the parasite flapping around as a permanent fixture in the fish's mouth for the rest of its life.
Why does it do this? We don't know, but we're going to go with the commonly held opinion that the cymothoa exigua simply thinks it's funny.
Imagine you're a happy grasshopper for a moment, joyfully kissing your grasshopper wife and kids goodbye as you leave the house, tiny briefcase in hand, ready to hop to work for the day.
Suddenly, on your way to the office, a sudden urge overtakes you, an urge that cannot be ignored. You obediently follow the siren song to the nearest body of water, and promptly fling yourself in. For weeks afterward, your widowed wife and friends will wonder what could have possibly made a perfectly happy and content grasshopper tragically commit suicide, by drowning no less. Depression? An affair gone wrong? Crushing gambling debts? No, it turns out it was just another strike from the soulless and evil menace known as the horsehair worm.
Resembling a coarse, thick horse hair (well, duh) the horsehair worm infiltrates insects, and sometimes even crabs, as a larva when the insect drinks tainted water. From inside the aforementioned grasshopper, the worm goes to work.
It weasels its way into the body cavity, and nourishes itself on the insect's tissues, sometimes growing up to a foot long. After a time, when the worm has matured, it starts to get horny, as teenagers do, and decides that the time has come to find himself a sexy mate. The problem is, all of the sexiest female worms hang out at the swimming pool club, and he's stuck inside of a prudish grasshopper.
That's a problem easily and dickishly solved by the horsehair worm, however, by simply reprogramming the insect's brain to seek out the nearest body of water and to hop right in, despite the sad fact that grasshoppers, like many other insects, can't swim.
As his former host panics and gasps its last breaths of sweet life, the worm casually slithers out of its anus, bids adieu to the drowning grasshopper and swims in search of the orgies of knotted up worms he's heard so much about.
Fucking mosquitoes. As if there weren't enough reasons to hate these living dirty needles, the bastards are responsible for yet more horrifying diseases thanks to the multitude of parasites they unwittingly inject into us every time they feed.
One such parasite is the almost too-weird-to-be-real filarial worm and, yes, it does affect humans.
After a year spent bumming around in our bodies, the worms mature into adults and finally take up the job they were born to do, by moving into the lymphatic system. Doesn't sound so bad...
Well, here's the thing. The lymphatic system keep excess fluids moving out of your body. It's one of those unnoticed bodily tasks that you don't appreciate until it stop working. Like if, say, a bunch of worms clogged it up. The filarial worm does just that, bunches of them all working hard in the vessels near the lymph nodes, causing those vessels to become obstructed and inflamed. Shit starts backing up, and the tissue starts inflating like a freaking balloon.
Finally, you wind up with massive and debilitating enlargements of the legs and genitals, a condition commonly known as Elephantitis. Goddamn mosquitoes.
Despite his rampant case of filarial worms, this man is still too proud to use only one flip-flop.