Causes

Naegleria infection is caused by the Naegleria fowleri amoeba, which is most often found in bodies of warm, fresh water around the world, especially during the summer months. The amoeba is also sometimes found in soil. The amoeba enters your body through your nose via contaminated water, mud or dust, and travels to your brain through the nerves that transmit your sense of smell.

Only a tiny percentage of the millions of people who are exposed to Naegleria fowleri ever get sick from it. Why some people become infected after exposure and others don't isn't known.

The amoeba doesn't spread from person to person. You also can't be infected by drinking contaminated water. Salt water, such as ocean and sea water, and properly cleaned and disinfected swimming pools don't contain the naegleria amoeba.