A single-celled parasite that enters human nasal cavities, consumes brain matter and typically causes death has been detected for the first time in Grand Teton National Park’s Kelly Warm Springs.
Water quality experts were aware from previous testing that the microscopic Naegleria fowleri amoeba was a resident parasite of the John D. Rockefeller Jr. Memorial Parkway’s Huckleberry and Polecat springs, and sampling this year found the pathogen there again.
Grand Teton officials aren’t entirely sure why the U.S. Geological Survey and Center for Disease Control found the little-understood amoeba for the first time in the lukewarm spring northeast of Kelly.
“What we don’t really know is if it is there all the time at the same level, or does it get masked sometimes and literally not show up?” said Sue Consolo-Murphy, Teton Park’s chief of science and resource management.
Naturally occurring organisms, she said, oftentimes ebb and flow.
The chance of infection from the parasitic amoeba, thought to occur in 85 to 115 degree Fahrenheit waters, is likely minimal.
High concentrations of E. coli bacteria also turned up in Kelly, Huckleberry and Polecat springs, yet no one is confirmed to have ever been sickened by the geothermal features in the past, Consolo-Murphy said.
But, she said, “We certainly think it’s possible based on these results.
“We were advised by the CDC and the Public Health Service to make people aware of these results so they can make informed decisions,” Consolo-Murphy said.
Soaking has been illegal since 2014 in the geothermal features of the parkway, Huckleberry and Polecat, which is administered by Grand Teton. It’s discouraged but not illegal in the weedy waters of Kelly Warm Springs, which are also a haven for exotic species like bullfrogs, goldfish and cichlids.
The CDC started sampling in March and has funding to study Naegleria fowleri in Grand Teton and the parkway through next year.
There is still plenty to learn about the amoeba, which normally subsists on bacteria but switches over to brain once it makes its way up a human host’s nose. It cannot be contracted via ingestion.
“It has not been a really very highly studied organism,” Consolo-Murphy said, “and there’s interest in learning more about its ecology and the conditions under which it maybe thrives.”
Naegleria fowleri is found not only in thermal waters, but also in ordinary freshwater, Teton park hydrologist Kathy Mellander said.
“All of the infections have taken place in the Southeast and South, until the last few years,” Mellander said. “There have been two infections in Minnesota.”
Infection from Naegleria fowleri causes an almost always-fatal central nervous system disorder called primary amebic meningoencephalitis. The past half-century the United States has averaged only about 2.5 cases a year, though the number tends to be higher in unusually warm years, according to the CDC.
Grand Teton officials aren’t sure if rising water temperatures played a role in Naegleria fowleri’s first-time detection in Kelly Warm Springs. The park will monitor temperatures in the three warm springs and other waters as well, Mellander said.
The brain-eating parasitic amoeba was also detected in geothermally heated Yellowstone National Park waters when monitoring was completed there in the 2000s, Mellander said.