Warm, still freshwater may host Naegleria fowleri, which causes a rare… (Brian Snyder / Reuters )
The deadly brain parasite thought to be responsible for the death of Florida teen Courtney Nash is as rare as it is dangerous. Tragically, it's also easily avoidable.
The 16-year-old began suffering from headache, stiffness, fever and nausea within a week after going for a swim on Aug. 3 in a local river. Doctors found the amoeba Naegleria fowleri in her system.
Amoebic meningoencephalitis is an exceedingly rare disease -- there are only a handful of cases each year, and unlike other forms of meningitis, this infection of the brain is not contagious and cannot be passed from one person to another. It is, however, extremely deadly, with an estimated 3% survival rate.
The amoeba grows best in warm bodies of stagnant freshwater (around 80 degrees Fahrenheit or higher, according to the Oklahoma Department of Environmental Quality). Its peak season appears to be in summer to early fall, when the weather is often at its warmest. Water traveling up the nose allows the amoeba to travel up the olfactory nerve and into the brain, where it starts feeding on nerve tissue.
Thus far there's not much that can be done to treat the disease; almost everyone who is infected dies, partly because by the time the cause is discovered the infection has progressed past the point of no return. One drug, amphotericin B, an anti-fungal drug, has been shown to be somewhat effective against the bug but can also cause irreparable kidney damage.
The easiest way to avoid the infection is by not swimming in bodies of warm, still freshwater -- or even poorly cleaned, inadequately chlorinated swimming pools. (There are plenty of other disease-causing critters in stillwater that you'd want to avoid, anyway.)
If you must swim in the local river or lake nearby, don't submerge your head in the water -- the amoeba enters up the nose so even accidentally swallowing some of that water might not be a problem (for this particular disease, anyway).
At the very least, nose plugs or nose clips might do the trick: Experts believe that water would have to be pushed forcefully up the nostrils to infect a person, so that might provide just enough protection, in the end.
More information from the Centers for Disease Control and Prevention on the infection.
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