When two otherwise healthy people who both irrigated their sinuses with tap water died from a rare amoeba infection, officials in Louisiana issued a warning to other neti pot fans to use only distilled or filtered water.
Brain-eating Amoeba Common, Infection Rare
The amoeba Naegleria fowleri is common in lakes and ponds, especially in the warm waters of the southern United States. But, the micro-organism can only kill if it is introduced directly to the brain, usually through sensitive sinus tissues. Of the 32 U.S. cases of primary amebic meningoencephalitis (PAM) caused by Naegleria fowleri in the last 10 years, 30 were in recreational swimmers who were infected by getting water up their noses.
Because Naegleria fowleri isn’t dangerous when ingested, there are no drinking water standards for it and even testing for contamination isn’t very common. It’s assumed that normal chlorination or other municipal water treatment eliminates enough of the pathogen to make tap water safe for drinking and bathing, but nasal irrigation may be a totally different matter.
Safe, But Not Sterile Tap Water?
“We consider chlorination to be effective in killing [N. fowleri],”United States Centers for Disease Control and Prevention (CDC) epidemiologist Jonathan Yoder explains in a FoxNews story. “I can’t comment on any water system in Louisiana, but in general … you may start out with 1 million amoebas and your goal is to reduce it with chlorine, and you might get 99.9 percent out. But you’re probably never going to eliminate 100 percent. That goes for amoebas, parasites, bacteria, viruses. So while we say our drinking water is safe, it’s not sterile.”
“If you are irrigating, flushing or rinsing your sinuses, for example, by using a Neti pot, use distilled, sterile or previously boiled water to make up the irrigation solution,” Louisiana epidemiologist Dr. Raoult Ratard said in a statement to reporters. “Tap water is safe for drinking but not for irrigating your nose.”
Will The Risk from Brain-eating Amoebas Increase?
Risks of contracting PAM due to Naegleria fowleri is much higher for outdoor swimmers. Any warm body of freshwater could harbor the amoeba and children and teens jumping and diving into waterholes and lakes during the summer are most at risk. In fact, four people died last summer from the same infection.
Officials noted that neti pot use is on the rise now that several celebrities have endorsed them for warding off winter colds and sinus infections. At least one report indicates that the first victim was probably a new neti pot user and failed to put salt in his solution, something that may have killed the amoeba and prevented inflammation of the sinuses that gave it easy access to his brain.
Still, Naegleria fowleri infection is so rare and the amoeba is common in so many states it is unlikely that any one state water authority would increase testing and establish new safety standards for the amoeba. Drinking water standards is one of many areas where state agencies often welcome federal expertise in evaluating the risks of the many chemicals and microbes found in our water supplies. Unfortunately, a majority in the U.S. House of Representatives seems bent on blocking the Environmental Protection Agency or any other executive branch agency from implementing new regulations.
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