Deadly brain amoeba may be tied to Katrina
NEW ORLEANS, La. (NBC) -- School officials in an area near New Orleans have shut off water fountains and stocked up on hand sanitizer this week after a brain-eating amoeba killed a 4-year-old boy and was found thriving in the local tap water system.
Water officials say they are “shocking” the St. Bernard Parish system with chlorine to try to kill off the parasite and get the water back up to a safe standard. And while health experts say the water is perfectly safe to drink, some school officials are taking no chances. They’ve shut off water fountains until they are certain.
Dr. Raoult Ratard, the Louisiana state epidemiologist, says the devastation wrought by Hurricane Katrina in 2005 may ultimately be to blame. Low-lying St. Bernard Parish, where the boy who died was infected while playing on a Slip ‘N Slide, was badly hit by the flooding that Katrina caused.
“After Katrina, it almost completely depopulated,” Ratard told NBC News. “You have a lot of vacant lots and a lot of parts of the system where water is sitting there under the sun and not circulating.”
That, says Ratard, provided a perfect opportunity for the amoeba to multiply. Without enough chlorine to kill them, they can spread.
The Centers for Disease Control and Prevention said on Monday that it had found Naegleria fowleri in St. Bernard’s water supply – the first time it’s ever been found in U.S. tap water. The amoeba likes hot water and thrives in hot springs, warm lakes and rivers.
Very, very rarely it can get up a person’s nose. If it gets in far enough – driven in, perhaps, when a child dives into a pond – it can attach itself to the olfactory nerve, which takes it into the brain. The multiplying amoebas eat blood cells and nerve cells and cause encephalitis. Only three out of the 130 people known to have been affected in the United States have ever survived, including a 12-year-old Arkansas girl, Kali Hardig, who is still recovering.
Chlorine kills it, but evidently some of the part of St. Bernard’s water system farthest away from the water treatment plan ran low on the chemical. CDC’s top water safety expert, Dr. Michael Beach, says that’s why it is important for officials to constantly monitor chlorine levels and make sure they are effective right to the end of the line of any water system.
Doris Voitier, superintendent of St. Bernard Parish Public School District, says the district shut down a second grade swim program briefly out of an abundance of caution to ensure that chlorine levels were sufficient. “The swim team is back in the pool. The swim program will be reinstituted within the next few days – hopefully by week’s end,” she told NBC News.
There’s no risk from drinking water that’s full of Naegleria, says Beach. Stomach acid kills it. And properly chlorinated pools are safe. The only risk is in the rare cases when it gets up the nose.
“As long as you know the top of your nose and where is the top of your nose, and where is the bottom of your nose, you will be all right,” says Ratard. There has been no increase in stomach infections in the region, he said, so other germs do not appear to be multiplying in the absence of enough chlorine.
“Drinking is always safe but if the water goes up your nose all the way to the ceiling of the nose then the amoeba can make their way to a little piece of bone between the top of the nose and the base of the brain. You have a small plate of bone with a bunch of holes inside,” Ratard says.
“The olfactory nerve sends a bunch of roots from the brain through the holes in the nose and that is how you smell.” The amoeba uses these nerve roots like a highway to the brain.
Low-lying St. Bernard Parish was almost completely devastated when Katrina hit in August 2009. Local officials have estimated that 80 percent of the structures in the parish were destroyed in the flooding, and the population plummeted from 67,000 to 8,000. It’s back up to about 35,000 now, according to the latest census, but state health officials say that still leaves a lot of empty lots, and reduced demand for water. That, in turn, means a lot of water sitting in pipes for longer times.
“Even if you have been away for a time, when people go away in summer to somewhere else where it is cooler, they should open their faucets and flush out any water that has been sitting there in the pipes,” Ratard advises.
CDC officials said they were not sure Katrina was to blame. “We're not aware of any linkage with Katrina,” Beach told NBC News.
But his advice is the same – people will be safe if they avoid having water go up their noses. People who rinse out their sinuses, as with neti pots or in some ritual ablutions, should use boiled water.
Parents who want to take extra care can add a few drops of chlorine bleach to bathwater or to kiddie pools to make the water safe, Ratard says. To be extra safe, they can make sure kids don’t put their heads under the water.
“The risk is extremely small,” Ratard said. “Some people will accept risk. Some people don’t want any risk.”
New Orleans tourism officials were concerned about the news coverage of the incident.
“This tragedy occurred in St. Bernard Parish, which maintains a totally separate water system from the City of New Orleans and Orleans Parish," a New Orleans Convention and Visitors Bureau spokesperson said in a statement.
"St. Bernard Parish water officials have taken precautions to cleanse their parish water supply for drinking water, out of an abundance of caution. This does not affect the water supply in Orleans Parish, where visitors come to experience the French Quarter, Garden District, Downtown, Uptown, Warehouse/Arts District, the Morial Convention Center and other popular tourist areas of New Orleans.”