Common Parasites In Humans Question

Parasites Symptoms answers:

You may want to consider doing something other than watching sensationalized melodramatic “documentaries” about evil brain bugs if it’s making you that paranoid.

To answer your question, though, if you simply want to know what percentage of humans carry some sort of other animal that lives off them, virtually all of us do, and the truth is stranger than you might imagine.

First, and perhaps my favorite, there is a species of mite which lives nowhere except in your eyebrows. They make their living by consuming oil and particulate matter which collects on the hairs of your eyebrows. Ever noticed that the rest of your hair gets oily if you don’t wash it, but your eyebrows tend to stay groomed? That’s why. There’s an entire species of arachnids dedicated to slaving their lives away just to groom your eyebrow hair.

Likewise, there is a species that lives in your eyelashes, doing the same thing.

There is a third species that lives on your face, especially on your forehead. When you lay down to go to sleep at night, they tend to become active and start looking for mating partners. Believe it or not, that’s one of the reasons your face starts itching as you’re trying to fall asleep. It’s a microscopic arachnid orgy on your face. If you’re wondering where they lay the eggs, the answer is “in your pores”, which sometimes causes zits and break outs (that’s why people’s complexion is often worse on their foreheads than other areas of their face… More mites = more eggs in the pores on our foreheads).

Finally, there’s a fairly common demodex mite that likes to live on the rest of human skin, and most people carry it. In dogs, they cause mange, but they usually don’t bother us unless they get completely out of hand.

It should be noted none of these species do us any harm as a matter of course. Even though they live on us, and live off us, their doing so largely seems to be to our benefit, if you don’t count the occasional blemish or dwell on the fact that them living on you means they also die on you, so in a way your entire body is a vast arachnid graveyard (have a good night’s sleep!).

Beyond that, there is a species of nematodes which likes to make its home under our fingernails (I find myself wondering how many kids would stop biting their nails if you told them they were eating tiny worms every time they bit their fingernails), which we also tend not to notice at all.

Getting into more pesky things, there are the usual list of offenders. There are flukes, fleas and ticks, the various lice, intestinal worms, trichinosis, the occasional leech and what not, but virtually all can be avoided with sanitation and hygiene. Infestations start becoming rarer from there.

Some parasites, such as screwfly larvae and guinea worms, can be absolutely Hellish to suffer through, but fortunately they’re uncommon. The guinea worm used to be much more widespread in Africa, but Jimmy Carter vowed he would keep fighting to see the guinea worm driven into extinction before he died, and at this point he’s almost succeeded. Less than 2,000 cases of infection were reported in 2010, with virtually all of them coming from one country (and that country has cut its rate of infection by over 70% since 2007).

Bottom line, unless you’re a parasite yourself, then parasites are something your species probably has to worry about, but humans are pretty well off in the grand scheme of things.

As for brain parasites being common? Not a chance. Your body has multiple defensive layers surrounding the brain for the express purpose of preventing just such a thing, because a parasitic infestation of the brain would certainly be devastating and almost inevitably fatal. That’s not to say it absolutely never happens (there’s toxoplasmosis, certain species of amoeba can infect the brain, etc), but infestation of the brain by any sort of parasite is EXCEPTIONALLY rare.

Parasites Symptoms answers:

I think the idea that humans are like viruses or parasites is more of an analogy. It was never a real theory, in the scientific sense of the word.

We just happen to overexploit our environment, and our populations grow out of control since we’ve eliminated most predators and figured out how to produce all the food we need. That’s not that different from any other species, though. If the local wolf population declines, for example, the deer population will skyrocket until they eat all the available food and start starving to death (and other species starve as well). Natural factors will eventually bring the population back into balance, but it might take a while. The only difference is that we humans have isolated ourselves from those factors – for the time being. Eventually we’ll probably run out of resources and nature will put us back in our place.

There’s no fundamental difference between us and any other life on the planet. Like I said, it’s just an analogy, and like any analogy, you can only take it so far before it starts to break down.