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Meet The Amoeba That Eats Your Brain

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Justine Alford

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1554 Meet The Amoeba That Eats Your Brain
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Since you all loved our recent story of a hideous amoeba infection that left a girl blind after she didn’t change her contact lenses, we thought we would introduce you to an even worse critter: Naegleria fowleri. This particular amoeba has also earned the nickname “brain-eating amoeba,” because, well, it eats your brain.

These microscopic, single-celled organisms are found worldwide in soil and warm fresh water such as lakes, rivers, hot springs or, more rarely, inadequately chlorinated swimming pools. Although exceedingly rare, it can cause a horrific brain infection called primary amoebic meningoencephalitis (PAM). PAM is uncommon, but has been reported in almost every continent. The majority of cases are within the USA.


The case fatality rate of this particular infection is around 97%. However, over the last decade there have only been 34 reported cases in the entire U.S. despite the vast amount of people that are exposed to water contaminated with this organism - so don’t sell your bikini on eBay just yet.

This organism usually lives off bacteria also dwelling in freshwater habitats, but it can infect humans if water containing the organism is forced up the nose for example during swimming or other recreational activities such as waterskiing or wakeboarding. In fact, an 8-month-old infant was thought to have contracted the infection from a full-submersion baptism dunking. You cannot acquire infection by drinking contaminated water.

From here, the organism attaches to and invades the mucous membranes lining the nasal cavity and then migrates along the olfactory nerve to the brain. The olfactory nerve carries sensory information about smell to the brain. It eventually reaches the olfactory bulbs, feeding on nervous tissue using sucker-like structures that sometimes make the organism look like it has a hideous face that wouldn’t look out of place in a horror movie.

This destruction of this area of the brain results in loss of smell and taste which occur around 5 days after initial infection. It then continues to migrate along nerve fibers, triggering an immune response that results in inflammation of the brain that sparks symptoms such as neck stiffness and headache.


As the infection progresses, secondary symptoms start to appear such as delirium, hallucinations and seizures. Eventually, the massive increase in pressure experienced from the inflammation causes the patient to die.

The majority of infections in the U.S. used to occur in southern states such as Florida and Texas; however, in recent years cases have been reported much further north. According to experts, it is possible that this is a result of climate change since N. fowleri requires warmer waters.

Just last week, it was reported that a 9-year-old girl from Kansas died from the infection after contracting the amoeba whilst swimming. Prior to 2013, it had been 35 years since a person survived this infection. During the summer of that year, two children, aged 12 and 8, survived PAM after taking a drug that was originally developed as an anticancer agent called Miltefosine. The former made a full recovery, but the second child was not so lucky and experienced permanent brain damage.

Once again, this is an extremely rare infection, so don’t change your summer plans just yet. But if you’re really worried about that waterskiing trip you’ve had booked for months- wear nose plugs as a precaution. 


healthHealth and Medicine
  • tag
  • amoeba,

  • naegleria fowleri,

  • brain-eating amoeba,

  • primary amoebic meningoencephalitis