August 22, 2011

Don't Let Amoebas Eat Your Brain!

Killer amoeba photo credit: DPDx

Seriously, you can be minding your own business and an amoeba can eat your brain?

Yep, we're not making this up.  There are indeed brain-eating amoebas out there, called naegleria fowleri by more scholarly types. They've killed a number of folks; at least three Americans have died this summer of n. fowleri infection.

Is there reason to panic? Well, here at Cranky Fitness we always advocate panic, just on general principle. (We had some great reasons, for example, to panic over the swine flu epidemic. Remember that?)

But as much as we always enjoy inciting a good panic attack, perhaps you'd like some more practical information on brain-eating amoebas, like where they lurk, and how to avoid having them eat your brain?

So here are the most important things you need to know about brain-eating amoebas.

Where can I find a more reputable source of information on naegleria fowleri, aka, Brain-Eating Amoebas?

Well, one place to start is the Web MD FAQ on brain-eating amoebas. In fact, it’s where most of the information in this blog post is swiped from! The CDC also has a naegleria fowleri FAQ.

What are Amoebas and How the Hell Do They Get In Your Brain?

Amoebas are single-celled organisms. If water or dust containing the brain-eating amoeba gets into your nose, you can get infected. The little critters then travel through the olfactory nerve into the frontal lobe of the brain and start chowing down. (It’s nothing personal; they’d actually prefer to eat bacteria).

How Often Do People Get Their Brains Eaten by Amoebas?

Not all that often. There are usually less than 8 cases a year of the brain-eating disease, called “primary amoebic meningoencephalitis” (or PAM for short). They almost always happen from July to September. Worldwide, there have been about 400 reported cases, and 35 in the U.S. since 2001.

Where Do The "Bad" Amoebas Live?

They mostly hang out in warm water. Places where shrieking sobbing hysterical paranoia caution may be advised include: warm lakes, ponds, puddles, slow-flowing shallow rivers, untreated pools, wells, hot springs, aquariums. And for those adventurous enough to consider them recreation areas, watch out for “thermally polluted water, such as runoff from power plants.”

Oh, and they can also sometimes be found soil, including indoor dust, which means… um… they could be anywhere.


(However, since so much emphasis was put on their warm-water haunts, I’m just going to ignore that thing about indoor dust and pretend they didn’t say that. Anyone else with me?)

Can Brain-Eating Amoebas live in ANY kind of water?

No! The good news is that you’re safe in salt water and in properly treated swimming pools or municipal water.

Do Amoebas Hunger After All Brains Equally?

Nope. Most of the folks who have gotten sick were in Southern or Southwestern states. And over half the cases of infection have been in Florida and Texas. But they seem to be acquiring more of a taste for northern brains, as evidenced by a recent case in Minnesota.

The Killer Amoebas like male brains better than female, and they prefer young brains to old ones. Over 60% of U.S. cases are in children age 13 or younger. About 80% of cases are in males. However, it isn’t clear whether the amoebas are picky, or whether young males are more likely to expose themselves.

If I'm Not Easily Scared, And I Want To Go Ahead and Swim in Warm Untreated Water Anyway, What Should I Avoid Doing To Keep My Brain Intact?

Don't get water up your nose! Infection seems to happen most often when people are diving, water skiing, or horsing around doing something that forces water into their nostrils. Infections have also occurred when people have dunked their heads in hot springs or “used untreated tap water to cleanse their nostrils.” (Nostril cleaning, really? Is it suddenly all that popular a pursuit?)

Also, you know those nerdy nose-plugs? Maybe it’s time to think about wearing one.

What Are the Symptoms?

It’s much like a case of viral meningitis; symptoms include “headache, fever, stiff neck, loss of appetite, vomiting, altered mental state, seizures, and coma. There may also be hallucinations, drooping eyelids, blurred vision, and loss of the sense of taste.”

Just How Screwed Are You if Brain-Eating Amoebas Get Up Your Nose?

It can take from 2 to 15 days for symptoms to appear. Many people have antibodies to N. fowleri, so your body may fight off the amoebas. However, if infected, it's over 95% lethal. Death usually occurs three to seven days after symptoms appear.

So Then I Clearly Need to Panic, Right?

As much as we approve of panic as an all-purpose reaction to anything unexpected, you probably don't need to freak out unless you (a) spend a lot of time in warm untreated water and (b) you are spectacularly unlucky. With only 8 cases a year the chances YOUR brain will get snacked on by amoebas is very, very low.

(And note: this amoeba disease thing may be extremely rare and overhyped in the media, but this post is NOT intended to make light of deaths and suffering caused by those few cases. That part is really tragic.)

So what do y'all think about brain-eating amoebas, are you scared?


  1. Well, since i just don't bother to go swimming any more, and i'm all for ignoring the indoor dust issue, i promise to only panic if i get a really stiff neck and fever at the same time.

  2. The poor little f*****s will starve if they try any of that nonsense on me.
    Seriously, it's one more thing to be aware of so thanks for the warning.

  3. Love Leah's comment. and not the serious one. LOL

  4. Makes me very glad to be a 41 year old female, living north of those scary locations, who rarely gets to go to the beach these days.

    Thank you for giving me something else to be paranoid about. :)

  5. Well, if I decide to go swimming in the great outdoors, I'll be sure to find some freezing cold water to do it in.

  6. I can't worry about this until I'm over Swine Flu and SARS.

    Amoeba kidding about that.

    Leah's comment cracked me up.

  7. It reminds me of that earwig on the old Twilight Zone episode, that crawled into the guy's ear and ate his brain. I've been anti-earwig ever since.

  8. Good thing I don't swim much. I like Leah's comment...they'd starve here too.

  9. Great timing here: having just spent the day taking a Red Cross canine CPR and first aid course, I'm primed to panic! After all that Airway, Breathing, Circulation, and how to recognize bloat and torsion, and the various types of poisoning, I'm thinking dogs almost always get water up their noses when they swim, and they like swimming in just the sort of water that harbors these critters. Are there any statistics on non-human mammals?

  10. Well, I don't do the swimming thing BUT I have heard these stories over the years & just recently again & they say more in the younger ones. Even being rare, it is something to pay attention to & the signs can be for other things so catching it early is so important. Better safe than sorry.

    Good post Crabby!

  11. he heh...good thing I have a level 3 biosuit here at work.
    Not sure how well it would stand up to swimming tho :)

  12. Aw, man. Just did a triathlon this weekend in an 86-degree freshwater lake.

    At least I'm well over 13. Hopefully my brain is too old for them :)

  13. I wish you hadn't written about this! Another sleepless night.

  14. Even though it's extremely rare, it's still scary! It's not something that should alter your behavior, but it can't hurt to be on the cautious side.

  15. Wish I would have heard about this before we spent a week on lake cumberland with 7 kids swimming all day. Instead I got to hear about the day before we were leaving. I would have for sure put noseplugs on them. It is very scary but such a small chance. I believe in natural healing so when we got home I had the family putting liquid Aqua Sol technology silver shield up our noses. lol


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