Primary amoebic meningoencephalitis (PAM), also called amoebic meningitis, is a serious disease that leads to inflammation of the brain. It’s caused by the Naegleria fowleri amoeba.
The Naegleria fowleri amoeba (a single-cell organism) grows in warm, untreated water and flourishes in temperatures between 25°C and 40°C. It can be found in stagnant water such as lakes and rivers or poorly maintained swimming pools, water hoses and spas, although it's extremely rare to contract PAM from a swimming pool.
PAM infection happens if water containing the Naegleria fowleri amoeba travels up the nose, through activities such as jumping, diving or falling into the water. The amoeba can then make their way to the brain, where it causes inflammation and destroys brain tissue. You cannot get PAM from swallowing infected water.
Although it is believed many people come into contact with the parasite, only a handful of people have contracted the disease.
Symptoms of PAM infection includes:
- high fever
- severe and persistent headache and pain in the forehead
- stiff neck
- confusion or hallucinations
- sore throat
- nausea and vomiting
- disturbances of taste and smell
- seizures (fits)
These symptoms are common for many other conditions, including viral and bacterial forms of meningitis. It’s important to urgently see a doctor for diagnosis.
While PAM infection can occur at any age, children and young adults seem more susceptible to the disease.
PAM is very rare and unfortunately the infection usually leads to death. Ways to help reduce the risk include:
- ensuring swimming pools are chlorinated and well maintained
- avoiding getting water up the nose in fresh water lakes and pools
- flush out old water before allowing children to play with hoses or sprinklers
- use fresh water in collapsible wading pools
- keeping your head above the water in spas
More information about the Naegleria fowleri amoeba and PAM infection can be found on the Centers for Disease Control and Prevention website.
Some state and territory health departments also provide information and frequently asked questions on PAM infections, such as:
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Last reviewed: March 2020