How to Care for Six Horrifying Parasites

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Tired of traditional pets? Dogs just consider you another pack member and cats have all those weird mommy issues. Luckily, there's another way -- and I'm not talking about investing in circus animals. If you want to grow attached to an animal friend, then why not try a pet that attaches to you?

Yes, internal parasites are all the rage among the modern, style-conscious pet owner. By allowing your pet to actually live inside your body, you cut down on most of the concerns associated with other pets. Forget litter boxes and morning walks -- these guys simply relieve themselves inside you. Worried about pet food? They depend on their host for nourishment, which means you can splurge on a nice dinner out instead of bleeding money for high-end pet foods.

So what do you say? Are you ready to welcome one of these loveable creatures into your heart (or maybe your small intestines)? Well, step right up and read about some excellent parasite choices, the benefits they offer and what all you'll have to do to acquire and care for them.

Originally published at Monsters Inside Me: Animal Planet.

My Filarial Worms
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Pets often depend on their masters to keep things tidy and filarial worms are no exception. Sure, Wuchereria bancrofti, Brugia malayi and B. timori all need your love, but they also require full use of your lymphatic system. You use its conduits to maintain a proper fluid balance between blood and tissue, but the parasites need that space to produce millions of microscopic larvae.

As a result, you can probably expect a certain amount of clogging down there -- sort of like if your cats decided to live in your air conditioning vents. Only instead of a stuffy room, the worms' living conditions tend to result in painful, disfiguring swelling in the legs and genitals -- also known as elephantiasis. The good news is that a rigorous personal hygiene regime can keep the swelling down. But even if it doesn't, isn't a little discomfort and a scrotum the size of a beanbag chair worth it to have millions of friends 24/7?

It's all about sharing. You can pick up your very own starter filarial worm through an infected mosquito bite. Infection takes 7-21 days.

Other selections: If elephantiasis is a deal breaker, be sure to consider the intestinal raccoon roundworm Baylisascaris or an internal colony of Schistosomiasis. You can recruit these fine parasites by eating raccoon feces or swimming in contaminated fresh water, respectively.

Cantonensis Love
Wikimedia Commons

Angiostrongylus cantonensis is an excellent choice for the discerning parasite owner -- especially those fond of fine French cuisine. Also known as the rat lungworm, A. Cantonensis typically carries out its lifecycle between rats and various species of snails and slugs. In other words, humans aren't typically on the menu -- unless you happen to feast on some raw or undercooked freshwater snails, slugs, shrimp, crabs or frogs.

Keeping any pet can be a headache and A. Cantonensis is no exception. No, seriously, they prefer to live in your brain so you're going to get headaches -- plus maybe stiff neck, nausea, vomiting, fever and skin irritation. In some cases, the parasite can also cause a rare type of meningitis called eosinophilic meningitis.

Of course, all good things must come to an end. Even if you manage to avoid medical treatment, rat lungworms die out on their own in a human host. But take heart! Once you've processed your grief (as well as the toxins released by the parasite's death), then your next A. Cantonensis may be as close as the nearest garden slug. Sometimes even a little unwashed lettuce is enough!

Other selections: While the rat lungworm can prove quite a memorable pet, some owners simply can't cope with the inevitable loss or all the snail eating. For these individuals, Cryptosporidium hominis and cutaneous leishmaniasis provide a nice alternative -- so long as you're cool with massive sores or diarrhea.

Got Botfly?
USC School of Medicine

One of the most rewarding aspects of parenthood is knowing that your love and hard work will provide a bright future for your child. Harboring parasitic botfly larvae is much the same. Nestled snuggly in the warm confines of your skin, it depends on your loving support (and tasty tissue) to enter the next phase of its lifecycle.

Botfly larvae enter the human body through mosquito bites (the adults actually lay their eggs on the unwitting delivery bug). Once inside you, they anchor themselves in place with hooks and raise a breathing tube up through the skin. Of course, you'll have to make sure you don't cover up the tube -- and certainly don't tug on it. Aside from killing your new pet, you could cause a serious infection.

Bear in mind that your new best friend is going to cause a certain amount of itching, as well as a shooting pain if it moves around too much. As such, try not to stress the little guy out. Avoid swimming or taking a bath, as these activities cause the larva to freak out over lack of oxygen. As your pet grows, a lump forms over the nesting site until the fully-grown larvae finally emerges painlessly. Think of it: The tiny larva has used your flesh to make itself a stronger body -- and eventually it will transform into a full-grown fly!

Other selections: If you're not up for such a commitment, you can always fallback on bed bugs -- which are becoming quite the fad again! You also might be interested in a chest full of lung flukes or a few screwworms if you happen to visit a country where they're still plentiful.

Wandering Strongyloides
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You know the old saying: " If you love something, set it free. If it comes back to you, it's yours. If it doesn't, it never was." Yes it applies to grown children returning home on holidays, but it also applies to the roundworm known as Strongyloides stercoralis.

Normally, your pet S. stercoralis carries out a very straight-forward relationship. In its dirt-loving infective form, it enters your skin and tracks a long, winding road through your lymphatic and repertory systems, till it finally reaches your small intestines. Here, the adult females make their home and, for up to five years, they pump out larvae. The young then leave home via your excrement to explore the world.

But empty bowel syndrome isn't a forgone conclusion with your roundworms, because sometimes the growing larvae don't actually leave. If you "happen" to have a case of constipation, they might wind up deciding to get to know their host a little better instead. This means a trip through the intestines wall and a weaving journey to such destinations as the lungs and liver.

Other selections: The small intestine isn't the only place to host your parasitic guests. Consider raising some Acanthamoeba keratitis in your eyeballs or strap on a few ticks for a chance at lucking out with some Babesiosis.

Pork Tapeworm Mania
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Chances are, your father probably ingested tape worms to help him keep that girlish figure while still putting it away at the dinner table. Wasn't that huge in the 70's and 80's? That particular tapeworm was a mere cestoda, however, not a pork tapeworm or Taenia solium.

The point is, T. solium isn't your father's tapeworm. Pet ownership isn't about simply letting a parasite leach off your meals while you reap the slimming effects. When you open your body cavity for a T. solium infection, you're letting in a creature that really wants to get to know you. Not just your bowels, but also your muscles, eyes, spinal cord and maybe even your brain.

If your pet pork tapeworms do make it into your eyeballs, you might experience a detached retina. If they make it into your brain or spine, you also might have to put up with a case of neurocysticercosis. Depending on how many lesions take up inside your skull, you might experience symptoms such as confusion, headaches, attention problems, vertigo, swelling of the brain and sudden death.

Other selections: While you should never choose a pet parasite solely for the neurological side effects, you can also cloud your brain with a nice Malaria fog. If you're a cat person already, consider rooting around in the litter box for a little toxoplasmosis.

Trypanosoma Slumber
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Pet ownership can change your life. A loving cat might bring out your compassionate side. Regular dog walks can help keep you more active. That's all well and good, but Trypanosoma brucei rhodesiense takes everything to the next level. This little parasitic protozoa can literally transform you into a different person.

Carried by the East African tsetse fly, a good infection of T. brucei rhodesiense can cause personality changes -- not in the touchy-feely sense, but in the clinical sense. Some people refer to the effects as East African sleeping sickness, choosing to focus on other symptoms, such as headache, skin rash, progressive confusion, irritability and eventual death if untreated.

But what kind of sensible pet owner focuses on the negatives? T. brucei rhodesiense offers you the rare chance to hold a dear friend so close that they're actually inside your central nervous system. Ready to transform your life? Just contact your local travel agent and ask about trips to rural East Africa.

Other selections: Too much of a wimp to let this ittle East African cutie change your life? Well, Naegleria fowleri can alter the way you perceive smells and Toxocariasis.

About the Author: Robert Lamb spent his childhood reading books and staring into the woods — first in Newfoundland, Canada and then in rural Tennessee. There was also a long stretch in which he was terrified of alien abduction. He earned a degree in creative writing. He taught high school and then attended journalism school. He wrote for the smallest of small-town newspapers before finally becoming a full-time science writer and podcaster. He’s currently a senior writer at HowStuffWorks and has co-hosted the science podcast Stuff to Blow Your Mind since its inception in 2010. In his spare time, he enjoys traveling with his wife Bonnie, discussing dinosaurs with his son Bastian and crafting the occasional work of fiction.