NEW ORLEANS — A potentially deadly brain-eating amoeba has been discovered in the St. Bernard Parish Water System that serves more than 44,000 people, and the system is being purified, state health officials said.
The Louisiana Department of Health and Hospitals notified the water system and parish officials Wednesday evening.
Olivia Hwang, a DHH spokeswoman, said the health department asked the water system to conduct a 60-day chlorine burn to ensure that any remaining amoeba in the system are eliminated. The chlorine burn will help reduce biofilm, or organic buildup, throughout the water system and will kill the amoeba.
Parish President Dave Peralta told the state the burn "may not be necessary, but out of an abundance of caution we're going to do it." He said the burn started at 6 a.m. Thursday.
No cases of infection have been reported.
It's the second time the Naegleria fowleri amoeba has been found in the water system in the last two years.
Peralta said the problem was found at a leaking sampling station, in a coupling that comes off a main water line. "Something ran into the line causing the leak and it was not reported to anybody," he said. Officials don't know when the line was damaged.
Based on current monthly chloramine residual compliance reports, health officials said the water system has met the requirements with Louisiana rules for chloramine disinfectant levels. Five other sites on the system tested negative for the amoeba and one site did not meet the required level of disinfectant.
Naegleria fowleri is an amoeba that occurs naturally in freshwater.
According to the Centers for Disease Control and Prevention, Naegleria fowleri infects people when water containing the ameba enters the body through the nose. It usually happens when they go swimming or diving in warm freshwater. It travels up the nasal tissues to the brain.
Hwang said the tap water in St. Bernard Parish is safe for residents to drink, but DHH is urging residents to avoid getting water in their noses.
Naegleria fowleri infections are extremely rare and testing for the amoeba in public drinking water is still relatively new and evolving, health officials said. Fewer than 10 deaths in the United States have been traced back to the amoeba, with three occurring in Louisiana over the last several years.
The amoeba was identified in St. Bernard Parish Water System in the summer of 2013. The U.S. Centers for Disease Control and Prevention confirmed that the system no longer tested positive for the presence of the amoeba in February 2014.
DHH samples public drinking water systems for Naegleria fowleri each summer when temperatures rise, Hwang said. "The amoeba are more active in hot weather," she said. So far, DHH has tested 12 other systems, including St. John the Baptist and DeSoto parishes, where there have been amoeba problems. DHH is still awaiting lab results for each, Hwang said.
Naegleria fowleri causes a disease called primary amebic meningoencephalitis, which is a brain infection that leads to the destruction of brain tissue. In its early stages, symptoms may be similar to bacterial meningitis.