The Louisiana Department of Health and Hospitals (DHH) announced that its testing confirmed the presence of the Naegleria fowleri ameba in the Ebarb Water District 1 Aimwell Area located in Sabine Parish. This water system serves 5,529 people. There are no known cases of illness related to the ameba in Sabine Parish or elsewhere in the state currently.

brain eating amoeba
Naegleria fowleri
Image/CDC

The water system was sampled as part of DHH’s surveillance program that launched earlier in Aug. 2014. During the ameba testing, DHH discovered the system was not in compliance with the State’s emergency rule, which requires water systems to maintain a minimum disinfectant residual level of 0.5 milligrams per liter throughout all of their distribution lines. This 0.5 mg/L level is known to control the Naegleria fowleri ameba.

The Department’s new ameba sampling program is currently in its third round of testing. Thus far, eight systems have been tested, in addition to water systems in DeSoto and St. Bernard parishes. Of the eight, DHH has results for six; two of those six tested positive for Naegleria fowleri.

Of the six for which results were completed, none had the required level of chlorine residuals. For the two water system sampled this week, both had chlorine residuals above the required 0.5 mg/l. Next week, the fourth round of samples will be collected.

Test results take approximately 14 calendar days to process. Test results for the third week will be available the week of Sept. 22. The test results for the fourth round of samples will likely not be available until the end of the month.

DHH has issued an emergency order requiring Ebarb Water District 1 Aimwell Area to perform a free-chlorine burn (maintain 1.0 mg/l of free chlorine throughout the system for 60 days) to kill the amebae within the water system.  The water will remain safe to drink during this time. At the end of 60 days, DHH will sample the system again for presence of the ameba.  In previous cases in Louisiana, this action has been effective in controlling the ameba. The emergency order also requires the system to achieve and maintain compliance with the state’s minimum chlorine residual of 0.5 mg/l throughout their system.

Ebarb Water District 1 Aimwell Area is the fourth water system in Louisiana to test positive for the ameba. Last year, testing by the Centers for Disease Control and Prevention (CDC) confirmed the presence of the ameba in the St. Bernard Parish Water System and DeSoto Parish Waterworks District No. 1. The St. John the Baptist Water System also tested positive for the presence of the ameba late last month. It is currently undergoing the 60-day chlorine burn. No known additional infections have occurred in DeSoto, St. Bernard or St. John the Baptist parishes, as incidences of infection are extremely rare. Testing in May on DeSoto Parish Waterworks District No. 1 and St. Bernard Parish Water System did not detect the ameba.

Once Ebarb Water District 1 Aimwell Area begins the chlorine burn, residents served by this water system may notice a change in the smell and taste of the water throughout the chlorine burn. However, the water will remain safe to drink. If residents are uncertain as to what water system they are served by, they should review their most recent water statement.

“There are simple steps that residents in the Aimwell Area can take to avoid exposure to Naegeria Fowleri, but tap water is still safe to drink,” said DHH Public Health Assistant Secretary J.T. Lane. “We spoke with local officials in Sabine Parish and the water district; they are working quickly to implement a chlorine burn in order to eliminate any ameba that may exist through the water system.”

“Warm summer weather is ideal for swimming pools and outside with tap water, such as on a slip and slide, so it is important for families to take precautions, especially for small children,” said Louisiana State Health Officer Jimmy Guidry. “The ameba can only infect a person through very small holes in the top of the nose that lead to the brain, so it is an extremely rare infection in humans. Even still, it is so important for families in the area to take precautions.”