Naegleria fowleri is a deadly single-celled amoeba that infects the brain when contaminated water enters the nose, leading to primary amoebic meningoencephalitis (PAM), which is almost always fatal.

The infection occurs when water containing the amoeba travels via the olfactory nerve directly to the brain, with symptoms appearing within 1 to 9 days and death often occurring within five days of symptom onset.

Naegleria fowleri causes a rapid and severe brain destruction, with early symptoms including headache, fever, nausea, and vomiting, progressing quickly to confusion, seizures, and coma.

Despite its dangers, brain-eating amoeba infections are extremely rare, with only 167 cases reported in the U.S. from 1962 to 2024, but the fatality rate exceeds 97%.

Between 1962 and 2023, 164 cases have been recorded in the U.S., with Texas and Florida experiencing the highest numbers, highlighting the rarity but seriousness of the infection.

Infections typically occur after swimming in warm freshwater lakes or rivers during hot weather, when water temperatures rise and water levels decrease, creating ideal conditions for the amoeba.

Recently, a case was confirmed in Missouri involving a man-made reservoir created in 1931, which is popular for recreation but was not previously known to be contaminated.

A Missouri resident was hospitalized with PAM after waterskiing in Lake of the Ozarks, suggesting water activities in warm lakes as a potential exposure source.

Health officials advise precautions such as holding noses shut, using nose clips, or keeping the head above water during warm freshwater activities, especially during high temperatures.

Early symptoms of PAM include headache, fever, nausea, and vomiting, with rapid progression to severe neurological symptoms and death, often within days.

There are no effective treatments for PAM, and survival remains extremely rare, with most patients suffering significant neurological damage.

The infection is not spread from person to person and is contracted through nasal exposure to contaminated water, not by drinking water.