Naegleria Infection
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Naegleria is a free-living ameba that is commonly found in the environment in water and soil. Infection of humans is rare but serious. To prevent infection with Naegleria, precautions should be taken to ensure that water does not enter the nose when participating in recreational water sports.  

Naegleria fowleri is found worldwide. It is most commonly found in:

Although Naegleria is commonly found in the environment, infection occurs rarely. Only 23 infections were documented in the U.S. between 1995 and 2004.  When infection does occur, it is most common during the dry, summer months, when the air temperature is hot, the water is warm, and water levels are low. 

Infection with Naegleria occurs when the ameba enters the body through the nose. Generally this occurs when people are participating in water-related activities such as swimming underwater, diving, or other water sports that result in water going up the nose. The ameba then travels to the brain and spinal cord where it destroys the brain tissue.  Infection with Naegleria causes the disease primary amebic meningoencephalitis (PAM), a brain inflammation.

Initial signs and symptoms of PAM start 1 to 14 days after infection. Symptoms include headache, fever, nausea, vomiting, and stiff neck. As the amebae cause more extensive destruction of brain tissue this leads to confusion, lack of attention to people and surroundings, loss of balance, seizures, and hallucinations. After the onset of symptoms, the disease progresses rapidly and usually results in death within 3 to 7 days.

Infection with Naegleria is very rare and the early symptoms associated with Naegleria may actually be caused by other more common illnesses, such as meningitis. To ensure prompt treatment, people should seek medical care immediately if they develop a sudden onset of two or more of the early symptoms (e.g., fever, headache, stiff neck) at the same time or if symptoms are unusually severe.

Several drugs are effective against Naegleria in the laboratory. However, although a variety of treatments have been used to treat infected persons, their effectiveness is unclear since most infections have still been fatal.

Naegleria infection cannot be spread from person-to-person contact.

Naegleria is found in many freshwater lakes and rivers in the United States, particularly in southern tier states. Therefore, it is likely that a low risk of Naegleria infection will always be associated with swimming in warm freshwater lakes, rivers, and hot springs. Some measures that may reduce this risk include:

	Warm bodies of freshwater, such as lakes, rivers
	Geothermal water such as hot springs
	Warm water discharge from industrial plants
	Poorly maintained and minimally chlorinated swimming pools
	Soil

	Avoid jumping into fresh water such as lakes, rivers, or hot springs during periods of high temperatures and low water volume.
	Avoid swimming or jumping into freshwater during periods of high temperature and low water volume.
	Hold the nose shut or use nose clips when jumping or diving into bodies of fresh water.
	Avoid digging or stirring up the sediment when in  shallow, warm waters.

For further information on protecting yourself from recreational water illnesses, go to http://www.cdc.gov/healthyswimming.

You cannot get Naegleria infection from a swimming pool as long as the pool is properly cleaned, maintained, and chlorinated.

This is for information only and is not meant to be used for self-diagnosis or as a substitute for consultation with a health care provider. If you have any questions about the disease described above or think that you may have a parasitic infection, consult your health care provider.