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Naegleria fowleri, the brain-eating amoeba, conmonly infects via the nose.
Following the September death of a young boy in St. Bernard Parish, La. from a brain-eating amoeba found in household water, state officials have confirmed the same amoeba has been found in a northern Louisiana parish's water. The amoeba, called Naegleria fowleri, which proves deadly if water is ingested through the nose, has also been identified in recent weeks in Florida, Mississippi and Arkansas.
The findings have some worried the deadly amoeba could turn up in even more faucets.
"We used to think of this particular amoeba as something that occurred primarily in Southern states," said Francine M. Cabral, a professor of microbiology and immunology at Virginia Commonwealth University, who has studied Naegleria fowleri for several decades. "But there have even been cases in Minnesota and further north, so we now know it can happen anywhere."
People infected with the amoeba, which was first discovered in 1965, are asymptomatic until it is actually feeding on the brain. Symptoms are then similar to other forms of meningitis, including severe head pain, neck pain, nausea, vomiting and rapidly increasing body temperature. Once the single-cell organism enters the nasal passages, it travels rapidly to the brain, and death usually occurs within one to two weeks from brain swelling and deterioration.
In response to the number of incidences in Louisiana, state health officials announced they will implement new standards to kill the amoeba in water systems by increasing the amount of chlorine and ammonia to disinfect the water. The standards will exceed federal standards issued by the Environmental Protection Agency (EPA), but it is unclear if other states will follow suit.
"There are two ways the amoeba gets in the water system," Raoult Ratard, Louisiana state epidemiologist told Discovery News.
"One would be through the filtration treatment plants, if it is not properly removed. The other is if there are breaks in the water lines, so that the amoeba can get in from other sources as it travels through the lines. If there is a good level of residue of chlorine, more than 0.5 milligrams per liter, then the amoeba should not survive."
Ratard said the filters being used now are the same as those used in dialysis, which not only improves the water quality, but also makes any amoeba present much easier to detect.
"The risk of the amoeba being found in the water supply could happen anywhere, because it is most often in warmer waters or in standing waters," Ratard said. "Areas where there is a lot of pollution in the water system are at risk, especially after a break in the lines, because there is so much material that is going to consume most of your chlorine, causing you to lose chlorine in a small part of the water system."
The Centers for Disease Control (CDC) reports there have been 130 cases of primary amoebic meningoencephalitis in the past 50 years, and only two of those affected survived. Between 2003 and 2013, 30 cases were reported with no survivors.
"For recreational sites, like water parks, the amoeba are in moist soil and when it rains if there is water around, the runoff will bring it from the soil to the water," Cabral said. "We know that it thrives in warm water, but now we also know that it can survive even in cooler water. So, swimming, diving, water sports can all be risky. You can’t be infected by swallowing the water. It has to enter through the nose, so we suggest using nose plugs or at lease holding your nose if you jump in the water."
The most pressing problem, according to Cabral, is that water is not routinely tested for amoeba in most municipalities. Instead, water is tested for bacteria that are more likely to cause intestinal problems. The most common of these is cryptosporidium, a parasite that needs a living organism from which to feed.
Naegleria fowleri, however is not a parasite like cryptosporidium, and it can feed off of everyday bacteria or yeast in the water.
In addition to avoiding submerging your head in high-risk water areas, the CDC also cautions users of a neti pot, sinus rinse bottles or other irrigation devices to boil their water for at least one minute before use.
It is important to note, said Cabral, that some people are more susceptible than others.
"Some physicians have found that if you have had a broken nose or deviated septum, or some other defect in the nasal area, you may be more susceptible to infection from Naegleria fowleri," she said. "Another thing we have found is that our complement immune system, our first line of defense in the body when an organism invades, somehow does not protect us against this amoeba."
Whether one will be negatively affected by the amoeba is unpredictable, said Cabral. "Many people can be exposed to the same water and maybe only one of them will be infected."