photo credit biospace.com

The unofficial end to summer is upon us and as we round the corner heading into Labor Day weekend, perhaps you will be interested in reading this post about the brain-eating amoeba that lives and lurks in our waterways, as told to you by 17-yr. old Janelle Fletcher, or Nelly, as her friends call her, “a fan of horror, thriller, and old scary movies,” which is probably why Naegleria fowleri appeals to her!  Warning:  the following is not for the faint of heart.  Happy swimming.

Studying the Brain-Eating Amoeba

by Janelle Fletcher

On August 2, 2020, Tanner Lake Wall, a thirteen year old boy from Palatka, Florida died after contracting an extremely rare and mostly water-based amoeba which triggered a disease known as primary amebic meningoencephalitis, or PAM, a brain infection that causes swelling of the brain and destruction of the brain and meningeal tissues, generally resulting in coma and death within 10 days after infection.  PAM is clinically similar to bacterial meningitis so the chances of being properly diagnosed with the disease are slim, lowering the already tiny chance of surviving the infection, and that, unfortunately, is what happened to poor Tanner.  According to the CDC, most people who contract the disease do not survive:  “Only 4 people in the U.S out of 148 have survived infection from 1962 to 2019.”  This means the brain-eating amoeba has a fatality rate of 97%. 

With such terrible survival rates, it’s important to be informed.  What, exactly, is a brain-eating amoeba?  How do you know when you have one?  And how do you prevent infection?

photo credit https://emedicine.medscape.com/

Naegleria fowleri, known as the brain-eating amoeba, is a free standing amoeba that does not need a human or animal host to complete its life cycles.  Originally discovered in Australia in 1965, it is believed to have evolved over time in the U.S. although from 2009 to 2018, only 34 cases have been reported.  As a small parasite, Naegleria fowleri travels up the olfactory nerve, one of the 12 cranial nerves leading straight to the brain, where it then takes up residence.  Usually this parasite eats bacteria, but when swept up into the human body, it uses the olfactory nerve like a trail to the brain which then becomes its food source.  As it begins munching on brain tissue, the human body sends white blood cells to fight the intruder and in response, the brain swells and eventually runs out of space inside the skull.  Most often, the person dies before being diagnosed. While it’s very rare to get this type of infection, there is also no good treatment for it.

Interestingly, 37 of the 148 known cases of Naegleria fowleri originated in Florida which is understandable when you see how the amoeba breeds. Naegleria fowleri can be found in warm still waters — the ameoba becomes dormant in cold water — such as mud puddles, slow flowing rivers, untreated swimming pools, even in soil, and can survive in waters as hot as 115 degrees Fahrenheit.  Water- based activities such as swimming, diving, water skiing — where water might be forced into the nose — and other water sports only increase the chance of being infected, especially in the months of July, August, and September.

photo credit CBS 17

Problematically, as symptoms related to climate change increase and small bodies of water lay dormant for longer periods of time on hotter days without recharge, incidences of Naegleria Fowleri could be on the rise.  If you experience symptoms within 2 to 15 days after doing water-related activities in potentially infectious water, you may have contracted the disease.  Symptoms may include: fever, headache, nausea, or vomiting, and later, stiff neck, confusion, lack of attention, loss of balance, hallucinations and sometimes seizures. Death generally follows five days after the last symptoms appeared. Studies also show that Naegleria Fowleri is attracted by the chemicals secreted by the nerve cells of the olfactory nerve which is how they end up in the frontal lobe of the brain.  There are some drugs able to kill the amoeba in test tubes, but when treated with these drugs, very few patients survive the ordeal.

But how can we keep this from happening?  As a public health intern, I would want to first figure out how or why people got infected with the parasite and work to prevent it from happening again. If participation in water sports increases risk of exposure, I would advise people to not swim in waters they are uncertain of during summer months, especially when there has been very little rain. Then I would promote proper cleaning of the nose after water sports and water-related activities. Naegleria fowleri is not contagious and cannot be contracted by drinking contaminated water; it only enters the body through the olfactory nerve.  And last but not least, I would spread awareness because not many people know about this tragic disease.

To prevent infection, avoid water sports in warm, still water during the months from July to September; do not stir up mud while doing certain activities; and properly clean your nostrils, not using tap water but distilled water.  Though the brain eating amoeba is very rare, I’d still be cautious of water and clean my nose properly after playing in the water because who knows? You’ll be prepared for the worst if you ever feel yourself ill with a headache turning into a stiff neck… 

Sources: https://www.cdc.gov/parasites/naegleria/index.html; https://www.today.com/today/amp/tdna191563; https://www.cdc.gov/parasites/naegleria/illness.html; https://youtu.be/2-CDcXUACos; https://youtu.be/V0-Fn-T0vgk