Photo Credit – Wikipedia Commons
Last August in Sometimes It’s Zebras I wrote about a rare, but nearly always fatal, type of meningitis caused by infection with the Naegleria fowleri parasite.
First described in 1965 by Fowler & Cutler of Australia, more than 140 cases have since been diagnosed worldwide.
Most occur in young children or teens exposed while swimming along the bottom of warm, often stagnant fresh water lakes or streams. Earlier this year, we saw two cases (one in Florida, one in Virginia) - of PAM (Primary Amoebic Meningoencephalitis) attributed to this parasite.
Both were acquired while swimming in freshwater lakes.
Several years ago N. fowleri contaminated tap water in Karachi, Pakistan was believed to have caused 13 cases over 18 months. All but one of these Pakistani cases denied recent freshwater swimming activities, but all routinely performed ritual ablution, which included taking tap water into the nostrils.
In recent years the use of Neti Pots – used for nasal saline irrigation – has become more common in the western world. I have one myself, and during allergy season I use it every day.
But today we’ve a cautionary note from the Louisiana Department of Health, after a second case of N. fowleri infection has turned up this year associated with the use of tap water and and nasal irrigation.
This press release is from the Louisiana Department of Health and Hospitals.
DHH warns residents about improper neti pot use
Tuesday, December 6, 2011 | Contact: Bureau of Media & Communications (225) 342-7913 or (225) 252-3579 (cell)
Baton Rouge—The Louisiana Department of Health and Hospitals is warning residents about the dangers of the improper use of neti pots. The warning follows the state's second death this year caused by Naegleria fowleri, the so-called brain-eating ameba. A 51-year-old DeSoto Parish woman died recently after using tap water in a neti pot to irrigate her sinuses and becoming infected with the deadly ameba. In June, a 20-year-old St. Bernard Parish man died under the same circumstances. Naegleria fowleri infects people by entering the body through the nose. A neti pot is commonly used to irrigate sinuses, and looks like a genie's lamp.
"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," said Louisiana State Epidemiologist, Dr. Raoult Ratard. "Tap water is safe for drinking, but not for irrigating your nose." It's also important to rinse the irrigation device after each use and leave open to air dry.
Naegleria fowleri infection typically occurs when people go swimming or diving in warm freshwater lakes and rivers. In very rare instances, Naegleria fowleri infections may also occur when contaminated water from other sources (such as inadequately chlorinated swimming pool water or heated tap water less than 116.6 degrees Fahrenheit) enters the nose when people submerge their heads or when people irrigate their sinuses with devices such as a neti pot. You cannot be infected with Naegleria fowleri by drinking water.
Naegleria fowleri causes the disease primary amebic meningoencephalitis (PAM), a brain infection that leads to the destruction of brain tissue. In its early stages, symptoms of PAM may be similar to symptoms of bacterial meningitis.
Initial symptoms of PAM start one to seven days after infection. The initial symptoms include headache, fever, nausea, vomiting, and stiff neck. Later symptoms include confusion, lack of attention to people and surroundings, loss of balance, seizures, and hallucinations. After the start of symptoms, the disease progresses rapidly and usually causes death within one to 12 days.
Naegleria fowleri infections are very rare. In the 10 years from 2001 to 2010, 32 infections were reported in the U.S. Of those cases, 30 people were infected by contaminated recreational water and two people were infected by water from a geothermal drinking water supply.
While the odds of contracting an amoebic infection of the brain this way are undoubtedly miniscule, these two recent reports out of Louisiana show they are not zero.
As this infection is almost always fatal, that makes the advice of using distilled, sterile or previously boiled water in your neti pot a reasonable enough precaution.