Showing posts with label parasites. Show all posts
Showing posts with label parasites. Show all posts

Tuesday, September 11, 2012

Naegleria fowleri wants to pick your brain (and eat it too)!


Ahhhh, the sweet relief of unclogged, gunk-free nasal passages! While neti pots and other nasal irrigation devices are weird, gross, and just plain awkward, there's nothing quite like being able to breathe freely out of both nostrils. And who wouldn't pour water through their nose if it meant curing the throbbing ache of sinus pressure?

Here's the catch: your sinuses are close neighbors to your brain. If a parasite hitches a free river ride through your nasal passages, into your sinuses, and up to your brain, a stuffy nose will be the least of your worries. Yes, frighteningly enough, this can actually happen. While rare, there have been reports of at least two individuals who have died from parasitic infections following nasal irrigation using tap water. In these cases, the water contained an ameba known in the microbe world as Naegleria fowleri and commonly referred to as the "brain-eating ameba". These parasites can travel to your frontal lobe via your olfactory nerve (the nerve that carries messages about smell from your nose to your brain). As its common name suggests, once N. fowleri reaches your brain it will begin feeding on it. This results in an infection termed primary amebic meningoencephalitis (PAM), a rapidly progressing infection that leads to seizures, hallucinations, and coma. PAM has a fatality rate of about 97%, and victims usually die within 1-2 weeks of symptom onset.

Because of the documented cases of PAM from neti pot use and the risk of infection by other microorganisms, the FDA has recently issued new guidelines for safely rinsing your sinuses. While salt solutions are supposed to be used for nasal irrigation, it would take approximately 18 hours for the salt to kill brain-eating amebas. The only real prevention is to use one of the following water sources when preparing nasal irrigation solutions:

1) bottled water that is labeled as "distilled" or "sterile"
2) water that has previously been boiled  for 3-5 minutes and cooled to lukewarm (if not used immediately, store in a clean and closed container for no greater than 24 hours)
3) tap water filtered through a pore size of 1 micron or less

If you tend to think like me, you'll be wondering: "if this ameba can be found in our tap water, how is it not killing off more people?" The answer is that if we gulp down one of these amebas in a glass of water, it will die once it reaches the vat of acid in our stomachs, leaving us unharmed. But be warned: these microorganisms are usually found in bodies of warm, freshwater and infection most commonly occurs during recreational water activities such as swimming and diving. Do what you will with that fun fact, but I'll be keeping my head above water.

Thursday, August 23, 2012

Toxoplasma gondii: Danger for Baby Mamas

As you may know, pregnant women are advised against cleaning cat boxes for the duration of their pregnancy. You may wonder if OB/GYNs banded together and declared that since pregnant women are busy growing human life in their wombs and all, they might as well be given a free pass from cat box duty for 9 months. Or perhaps it is because if a pregnant woman stoops down to clean the cat box she'll get stuck? These seem like legitimate enough reasons to me, but if you need more incentive to keep pregnant ladies away from cat boxes, try this one on for size: PARASITES! Yep. There is a parasite (a protozoan parasite to be scientifically accurate) named Toxoplasma gondii that can be transmitted in cat poo. Most people who become infected don't get sick because their kick-ass immune system takes charge before the little buggers cause any harm. At the most, they might get flu-like symptoms and never suspect that a cat poo parasite is the culprit. However, if a pregnant women becomes infected for the first time (i.e. she has no previous immunity) she can pass the infection onto her unborn baby. This can result in miscarriage, giving birth to a stillborn baby, or giving birth to a baby who goes on to develop vision loss, mental disability, or seizures. Is that reason enough??

Side note: Recent press has scared cat ladies everywhere by claiming that Toxoplasma gondii causes brain cancer. These rumors have been put to rest. Cat ladies should only worry about their cat negatively affecting their health if they happen to be pregnant cat ladies. Even then, there is no need to avoid your feline friends, just avoid their poo box.