The detection of Naegleria fowleri in popular national parks poses a significant health risk to visitors engaging in water-based recreational activities. The amoeba is known to cause primary amebic meningoencephalitis, which has a fatality rate of 97%, according to the Centers for Disease Control and Prevention. While infections are exceedingly rare, the parasite's ability to thrive in warm freshwater and its potential spread due to rising global temperatures are concerning. Visitors to affected parks, particularly Yellowstone, Grand Teton, and Lake Mead, should exercise caution when swimming or engaging in activities in warm, stagnant water bodies.