Naegleria fowleri: Risks of the lethal brain-eating amoeba

Naegleria fowleri, commonly known as the ‘brain-eating amoeba’, is a rare but highly lethal microorganism found in warm freshwater environments. The amoeba thrives in temperatures exceeding 30°C, making it more prevalent in lakes, rivers, ponds, and hot springs during summer months. It can also occasionally be found in poorly maintained swimming pools or domestic hot water systems.

Infection occurs when water enters the body through the nostrils; the amoeba travels along the olfactory nerve to reach the brain. This process triggers a severe inflammation known as primary amebic meningoencephalitis, which rapidly destroys nerve tissue and causes significant cerebral edema.

Symptoms typically appear between one and nine days after exposure, often initially mimicking flu-like or viral meningitis symptoms, such as intense headache, fever, nausea, and vomiting. As the condition progresses, neurological signs including neck stiffness, confusion, loss of balance, light sensitivity, convulsions, and coma may occur. The disease is characterized by its rapid progression, with death often occurring between one and eighteen days after the onset of symptoms.