How To Avoid Getting Sick While Swimming This Summer

Now that the weather is warming up and we’re all starting to dream about lazy afternoons spent lounging in or around a large and refreshing body of water, it’s time for your annual reminder that swimming is kind of gross: Pool-induced diarrhea is on the rise, according to the Centers for Disease Control and Prevention (CDC), thanks to a growing number of outbreaks of something called Cryptosporidium. A parasitic infection that likes to hang out around swimming pools and water playgrounds, Cryptosporidium — or simply Crypto for short — manifests in humans as diarrhea of the watery variety, stomach cramps, nausea, and vomiting; dehydration can also occur, which honestly isn’t all that surprising, given the sheer variety of ways in which Crypto can deprive you of fluids. The good news is that you can take precautions to guard yourself against the infection… and the bad news is that you probably just read this right around lunchtime. Uh… sorry about that.

In any event, a recent Morbidity and Mortality Weekly Report from the CDC published on May 18, 2017 discovered that twice as many outbreaks of Crypto were reported in 2016 as they were in 2014. In 2014, only 16 cases of Crypto linked to swimming pools or water playgrounds were reported in the United States; in 2016, however, the number rose to 32. Worth noting is that we don’t know whether this number has risen because the actual outbreak count has increased, or whether we’ve just gotten better at tracking them — but either way, it can’t hurt to brush up on your pool health safety.

According to the Mayo Clinic, Crypto infections can result from ingesting the one-celled parasite; after the parasite has made its way to your intestinal track, it likes to make its home in the walls of your intestines, at which point it begins producing more cells and releasing them into your feces. How exactly does one ingest Cryptosporidium, you ask? Any number of ways, one of which is — you guessed it — swimming in contaminated water and accidentally swallowing it. You can also end up with Crypto in your guts after touching something that’s been contaminated and then putting your hand to your mouth. Indeed, the CDC notes that Crypto is particularly tough to eradicate; chlorine doesn’t necessarily kill it, and it can survive up to 10 days even in treated water.

If you fall prey to Crypto, you’ll first begin to experience symptoms about a week after infection. In addition to the diarrhea, cramps, and nausea issues I mentioned earlier, you might also experience a loss of appetite, sudden weight loss, or fever. You’ll likely suffer from these symptoms for two to three weeks, depending on who you ask (the Mayo Clinic says up to two, while the CDC goes with three); however, they might continue to plague you on and off for up to a month. Don’t let it go that long without getting it checked out, though — the Mayo Clinic recommends visiting a doctor if you start seeing watery diarrhea that lasts for more than a couple of days.

So: How exactly does one avoid getting infected by this obnoxious little parasite? In the words of Mad-Eye Moody, by practicing constant vigilance. Here are some swimming dos and don’ts for keeping yourself Crypto-free: