Naegleria fowleri and Public Water Systems | Naegleria fowleri Infection | CDC

Although rare, Naegleria fowleri has caused deaths that have been associated with disinfected or untreated public water systems, both in the United States and in several other countries. If Naegleria fowleri is suspected to have contaminated a public water system, people should take steps to keep water from going up their nose, which could cause a serious brain infection.

Naegleria fowleri can cause primary amebic meningoencephalitis (PAM), a rare brain infection that is nearly always fatal. Most PAM infections happen after a person gets water in their nose from lakes, rivers, or other untreated freshwater bodies.

Naegleria fowleri has caused deaths associated with disinfected public water systems and an untreated, geothermal well-supplied water system in the United States. Disinfected public water supplies contaminated with Naegleria fowleri also have been linked to deaths in Australia and Pakistan.

If Naegleria fowleri is suspected to have contaminated a public water system, the water utility may raise disinfectant levels and flush the system. When this occurs, the water may have a strong chemical taste or smell. The water utility will work to make sure that tap or faucet water still meets drinking standards.

A layer of scum or biofilm that usually coats pipes in water systems and homes could contain Naegleria fowleri. Some of the contaminated layer could come loose in a water system or household tap or faucet water when the utility raises disinfectant levels.

People served by a public water system that has been determined to contain Naegleria fowleri should take extra steps to keep tap or faucet water from going up their nose. When Naegleria fowleri travels from the nose and to the brain, it can cause PAM.

Recommendations for people using a water system contaminated with Naegleria fowleri include: