It's Shark Week once again, and it's that time of the year when our fear of sharks skyrockets. To be fair, sharks can be terrifying. A lot of us probably grew up watching movies and shows wherein a shark fin slicing through the water signals a bloody end while ominous music plays.
However, the fact remains that you're very unlikely to suffer a shark attack. You have better chances of getting struck by lightning than getting attacked by a shark.
That said, there are other things in the water that warrant your terror more.
People colloquially refer to Naegleria fowleri the “brain-eating amoeba”, which definitely conjures up some unpleasant images. Even more terrifying is its fatality rate—N. Fowleri has killed 97% of people it has infected.
N. Fowleri lives in freshwater and infects you when you get it up your nose. The amoeba travels up to your brain, and five days later, you'd be suffering the symptoms of infection. Infected people suffer hallucinations, seizures, extreme headaches, and fever, all of which eventually lead to a coma.
Summer is the time for beaches, pools, popsicles—and cyanobacteria. As temperatures rise due to global warming, there may be more and more outbreaks and cyanobacteria blooms in the future. Now that's definitely worse than the terror of Shark Week.
Fertilizer runoff fuels the growth of cyanobacteria. When this happens, the bacteria get all over beaches, lakes, and other bodies of water. Once you come into contact with the bacteria, you may get irritated eyes, skin, and throat. Swallowing water with cyanobacteria, however, is another thing entirely. You can get headaches, vomiting, and even liver damage if the infection is severe.
Here's what's scary about cryptosporidium: it takes just 10 of them to make you sick. Worse? An infected individual can excrete up to 100 million cryptosporidium in one bowel movement.
The math of this parasite is indeed scary. Not only can one person infect countless others, infections have also doubled in the past few years. It's not the kind of thing that's exciting enough for Shark Week, but it's just as—or even more so—terrifying. Infected animals and humans can spread the parasite quite easily. The infection is also quite a common occurrence in public pools and water parks, since chlorine is harmless to cryptosporidium.
This is yet another infection that spreads through stool. Just 18 of the viruses can make you sick with vomiting and diarrhea. People sometimes mistakenly think that they're suffering from a stomach flu, but they're actually suffering from a norovirus infection.
As of yet, we don't have a vaccine for norovirus. However, scientists are hard at work trying to finally come up with a vaccine. The work may be a bit slow, but we can be optimistic about it.
Legionella is unique in this list in that it doesn't mess up your gut. Instead, it targets your airways. If you like getting into hot tubs, you may want to keep an eye out for Legionella. Legionella thrives in warm water, so hot tubs seem to be a prime place to be—for the bacteria, that is.
The bacteria can cause two respiratory diseases: legionellosis and Legionnaires' disease. It's also possible to get a milder condition called Pontiac fever. Legionella is loads better than the gory stuff we see on Shark Week, but it's still something we should do our best to avoid.
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