The Freshwater Threat That Could Ruin Your Summer Fun

Who doesn’t enjoy a day out at the lake to cool off from the summer heat? It can be refreshing to splash around and get silly with friends and family. Most of the time, as long as we take the proper safety precautions, we can enjoy the water with few worries.

Or we could. Organisms that were once rare may surge as climate change accelerates so it behooves us all to be aware. Here’s what to watch out for when seeking out freshwater swimming sources.

Brain-Eating Amoeba

News reports pop up every year or so, covering new devastation from an old threat. Single-celled organisms called free-floating amoeba usually live peacefully in many freshwater bodies across the country. Typically, they stay in the sediment on lake floors, but when heavy rains or other types of activity kick the dirt up into the water, the threat of exposure increases — and then we swim or play in it unknowingly.

When these microbes find a way into our systems, usually through water that's gotten up the nose, they can enter our brains. There, they feast as they would on the lake floor, devastating their victims. It sounds like science fiction, but it's very real.

There are three major “brain-eating amoeba” in the United States:

  • Naegleria fowleri lives in freshwater bodies all across the world. In the United States, this microbe is most common in southern states, although its span is growing. The only way to become infected is through the nose. For reasons still under investigation, only some people exposed to N. fowleri fall ill. Which is why there have only been 148 documented cases of these who do. The CDC reports that this parasite has a 97% fatality rate, and death typically occurs within 12 days of symptom onset.
  • Balamuthia mandrillaris infections have occurred in California, Arizona, Texas, Mississippi, Hawaii, Georgia, Florida, New Mexico, Illinois, Virginia and Washington. Most people who contract this amoeba generally die within 24 days of symptom onset, although some patients have survived as long as 450 days. The fatality rate is 90%. B. mandrillaris can also thrive in dry soil, not just water, infecting some sufferers via inhaled kicked-up dirt and dust.
  • Acanthamoeba species are found worldwide, and are capable of surviving in water, soil and air, but infections are incredibly rare. Most healthy people seem capable of fighting it before it takes hold, although those with impaired immune systems are susceptible to infection. Central nervous involvement with this amoeba has a 100% fatality rate.

The best way to avoid a brain-eating amoeba infection is to refrain from activities in freshwater rivers and lakes that could result in water being splashed or inhaled up the nose. Consider wearing nose plugs if submersion or splashing might occur.

It’s also important to take precautions when performing nasal irrigation; tap water can be contaminated, so only distilled water should ever be used.

Summer should be fun, but safety should always come first. Be aware of the threat and avoid playing in or letting kids play in murky water, which means sediment may have been kicked up. Free-floating amoeba can be anywhere, though, and all it takes is one mistaken move for an infection to take hold. It's probably a good idea to plug the noses of kids before letting them splash in lakes, too. So go have fun! And, as always, don't forget the sunscreen.

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7/9/2021 7:00:00 AM
Wellness Editor
Written by Wellness Editor
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