Naegleriasis (or amoebic meningoencephalitis or AMP) is a fatal infection of the brain by the single-celled, free-living eukaryote Naegleria fowleri. (Photo by: CDC/IMAGE POINT FR/BSIP/Universal Images Group via Getty Images)
A newly released study discovered a deadly, brain-eating amoeba in three U.S. National Parks and recreation areas, two of which rank in the top ten for most popular in the nation.
Big picture view:
The amoeba in question, Naegleria fowleri, was found in recreational thermal waters at the greater Grand Teton National Park and Bridger-Teton National Forest region, Lake Mead National Recreation Area, and Yellowstone National Park, according to the study published by the American Chemical Society.
Researchers from the U.S. Geological Survey, Montana State University, and Commonwealth Scientific and Industrial Research Organization noted that the concentrations detected at Grand Teton and Yellowstone were higher than ones reported at places where known infections have happened. While infections are rare, the study notes that the disease it causes has a 98% fatality rate.
Map of the western United States showing all five sample regions, including Grand Teton National Park, Lake Mead National Recreation Area, Newberry National Volcanic Monument, Olympic National Park, and Yellowstone National Park. (Source: ACS)
Where the brain-eating amoeba was found
The study targeted sites or waters at five national parks or recreation areas that also included Newberry National Volcanic Monument and Olympic National Park. It included a list of the locations where the N. fowleri was reported, including many where the amoeba may not have been detected before (noted with an asterisk):
- Blue Point Hot Spring*
- Boiling River
- Boy Scout Hot Spring*
- Firehole River
- Huckleberry Hot Spring
- Lewis Lake Hot Springs*
- Nevada Hot Spring*
- Polecat Hot Spring
- upper Polecat Hot Spring*
- Rogers Hot Spring*
No fatal infections have been reported at any of those locations, researchers noted.
The backstory:
Researchers took 185 samples between 2016 and 2024 and found N. fowleri in 63, or 34%, of them.
While the study did not find N. fowleri at Newberry and Olympic, a related amoeba was discovered. Researchers detected N. australiensis in those two locations as well as Grand Teton, Lake Mead, and Yellowstone. The authors noted that that type has never been known to have infected a human, but has shown pathogenicity in mouse studies.
What you can do:
The study’s authors wrote that their findings highlight the importance of increased monitoring and risk management strategies in the type of recreational waters where the amoeba was found; they also stated that a public awareness campaign is important.
According to the study, a person would become infected when contaminated water enters through the nose, not by swallowing it. Common risks include swimming, diving, or bathing in water where the amoeba is present or using untreated water for nasal rinsing.
The Source: Information for this article was taken from a study published by the American Chemical Society and National Park Service. This story was reported from Orlando.