Naegleria Infection is a rare but severe and fatal brain infection caused by an amoeba called Naegleria fowleri. N. fowleri is found in warm freshwater and its surrounding soil.  People who go swimming in warm freshwater (i.e., lakes, rivers, and hot springs) can get infected. This “brain-eating amoeba” enters through the nose and climbs up, invades the brain and destroys brain tissue, and damages cells in human blood vessels.

Naegleria infections are rare. Cases occur mostly during the summer months. Infections are likely to happen during months of high temperature because water temperature also gets tall, and water levels are low. This is the most favorable environment for N. fowleri. There is a small risk of contamination in properly chlorinated swimming pools and spas. However, in sporadic cases, the brain-eating amoeba has been found in poorly-maintained, and minimally-chlorinated swimming pools, and tap water. However, note that drinking contaminated water cannot get you infected, and the disease is not contagious.


The symptoms start within the first week after being exposed to the N. fowleri in two stages. The first stage of symptoms includes:

  • Severe headache
  • Fever
  • Nausea
  • Vomiting

In stage two, an individual will experience:

  • Stiff neck
  • Seizures
  • Loss of balance
  • Lack of attention to people and surroundings
  • Confusion
  • Altered mental status
  • Hallucinations
  • Coma

When the infection begins to manifest itself in symptoms, the disease can progress rapidly and cause death within about five days. People with stage one symptoms shall immediately seek out medical care, especially when they have been swimming/diving in contaminated bodies of freshwaters within two weeks.


Naegleria infection can be diagnosed using different tests and procedures:

  • CT Scan and MRI: the two imaging tests can reveal brain swelling and bleeding.
  • Routine blood tests: will be conducted to find out if there are infections.
  • Spinal tap (lumbar puncture): a sample of cerebrospinal fluid will be collected by inserting needles between two vertebrae. The sample fluid will then be examined under a microscope to see if the Naegleria amoeba is present and if there are inflammatory cells present. The fluid can also measure cerebral spinal fluid pressure.


Treatment consists of antifungal drug amphotericin B, which can kill the pathogen. Even with this treatment, the fatality rate remains at 96%. Miltefosine is another investigational antiparasitic drug that can inhibit the pathogen. This drug has been used in some cases and has shown improved survival of patients.

The best treatment is still prevention. To prevent Naegleria infection, you must avoid water-related activities in untreated water, especially during months with prolonged hot temperatures. You can also observe the following precautions:

  • Make sure that the water will not enter your nose. Use nose clips.
  • Keep your head above the water when swimming in hot springs or other thermal untreated waters.
  • When flushing your sinuses, use water that has been filtered or previously boiled.
  • Avoid playing, burrowing, or digging sediments in low, warm freshwater areas.

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