The news if full of stories about the recent deaths in Louisiana from infections with Naegleria fowleri, often called the brain-eating amoeba. This is a very rare infection caused when this amoeba that is found most often in warm fresh water lakes and streams gets into the nose and then infects the brain leading to it’s moniker as the brain eating amoeba. The result is a usually fatal amoebic meningoencephalitis. At least one of the cases in Louisiana seemed to be related to use of non-sterilized tap water in a Neti Pot solution.
You may know about neti-pots and sinus rinse being used for management of various nose and sinus problems, and I’ve long been a strong proponent of sinus rinse therapy. I tend to prefer the much simpler to use sinus rinse bottles to the Neti-pot, but they are both very effective. I have not been rigorous about telling patients to use distilled or previously boiled water for this use, but after these admittedly rare but preventable issues I plan to change this advice.
Naegleria fowleri is the only species in the Naegleria family of amoeba that causes infection in humans. Most commonly this infection occurs after swimming in infested waters. The life cycle of the Naegleria fowleri organism is in three stages. The organism can exist as cysts, essentially a resting stage, as trophozoites which is the infectious stage to humans, and a flagellated stage. If the trophozoite enters the nose it can migrate through the olfactory nerve up through the top of the frontal sinuses into the brain where it can cause primary amoebic meningoencephalitis. Typically trophozoites are seen in brain tissue and cerebrospinal fluid (CSF), but occasionally flagellated forms are seen in CSF.
In the US Naegleria fowleri is found primarily in warm water of the southern tier of states. It is also sometimes seen in geothermal springs and in industrial warm water effluent or heated poorly chlorinated swimming pools or hot water heaters not kept at temperatures over 47 degrees C (116.6 degrees F).
Naegleria fowleri amoebic meningoencephalitis is rare. In the years from 2001-2010 according to CDC records only 32 cases were documented in the U.S., with 30 being from recreational water activities and 2 from a contaminated geothermal drinking water supply. (1)
The CDC site notes that in southern states there is a high incidence of Naegleria fowleri in the waters, yet the very rare cases of brain-eating amoeba infections due to Naegleria fowleri make it clear that the risk of any given exposure to these waters is very low. Now using sterilized water for Neti Pot solution recipes and sinus irrigation seems a reasonable additional step to avoid brain eating amoeba infections.
To check out other uncommon and strange diseases also see: