After a 9-year-old Minnesota boy died recently of a brain infection caused by the microorganism Naegleria fowleri, officials at the Three Rivers Park District are saying that the lakes and beaches are safe. The boy was the second child in two years to succumb to the amoeba after swimming in Stillwater’s Lily Lake.
Rick Brasch, the senior water resources manager for Three Rivers Park District, said that while Naegleria is common in Minnesota, infection is anything but.
“It’s really, really, really rare: The two fatalities over in Lily Lake are the only ones I’ve ever heard of from this particular organism in the state in 20 years of working on lakes,” he said. “It’s very clear that the incidence of this thing is higher—even though it’s still very low—in the southern states because it thrives in much higher water temperatures than we’re likely to see up here—at least up until now.”
Brasch said the risk of fatal exposure to Naegleria is dwarfed by the risk of drowning.
Between 2002 and 2011, there were only been 28 reported infections in the United States, according to the Centers for Disease Control and Prevention.
For the area’s swimming ponds, at Elm Creek and Lake Minnetonka, the risk is even lower.
“Swimming ponds are as close to zero risk as you can get because they’re chlorinated,” Brasch said.
Brasch said that after the Stillwater boy’s death, the park district considered testing for Naegleria but decided it wasn’t feasible.
“The test for Naegleria is pretty expensive and very time-consuming and isn’t amenable to a quick assessment like we have for bacteria,” he said, noting that, for bacteria “we can turn the test around in 18 hours and decide whether to close the beach if it has high bacteria levels.”
Brasch said the low incidences of Naegleria infections make hypotheses tenuous but that there is speculation that higher temperatures could lead to a greater risk.
“Especially with water temperatures on the rise, we’ll be interested in tracking any reasonable way we can test for it in the future,” he said. “The CDC, as I understand it, is working on a quicker test, and we’re following that for our own edification.”
Three Rivers Park District has swimming beaches at several regional parks including, Elm Creek Park Reserve and Fish Lake Regional Park in Maple Grove, French Regional Park in Plymouth, Lake Minnetonka Regional Park in Minnetrista and as well as others. Three Rivers Park District serves the Hennepin County area.