Before you dive off the diving board at your favorite swimming pool, you might want to take a closer look — and sniff — at the water down below. According to the Centers for Disease Control and Prevention (CDC), the cases of recreational water illness (RWI) in the United States are on the rise and those illnesses are caused by germs and bacteria that may be lurking in your nearby pool.
According to the CDC, 90 illness outbreaks were reported in 32 states and Puerto Rico between 2011 and 2012. These outbreaks sickened at least 1,788 people, resulting in 95 hospitalizations and one death. And these outbreaks from pools and water playgrounds doubled in the United States from 16 in 2014 to 32 outbreaks in 2016, according to a CDC report. Nearly 2,000 people got sick in Ohio alone in 2016, the CDC says.
Here's where it gets icky
So what's making everyone so sick? The majority of illnesses were associated with the bacteria Cryptosporidium.
Between 2009 and 2017, there were 444 outbreaks of crypto, resulting in 7,465 cases that were reported in 40 states and Puerto Rico, according to the CDC. The number of reported outbreaks has increased an average of about 13% per year. (The CDC notes that the spike could be due to new testing technology that makes crypto easier to detect.)
Crypto can survive in swimming pools for 10 days or more even in chlorinated water. And just how does crypto get into pool in the first place? Brace yourself...this is going to get gross.
Michele Hlavsa, lead author of the CDC report, told CBS News. "Swimmers bring [crypto] into the water when they are sick with diarrhea."
The CDC advises people never to swim when they have diarrhea, but unfortunately, that doesn't stop everyone from doing it. This quick YouTube clip was the winner of CDC’s Healthy Swimming program video contest and it sheds some levity on what might otherwise be considered a puke-inducing conversation:
If you contract the bacteria, symptoms include watery diarrhea, stomach cramps, nausea and vomiting.
But diarrhea isn't the only thing you need to worry about in the pool. There is also urine. In fact, researchers have shown that it isn't chlorine that causes your eyes to get red when swimming in a chlorinated pool. It's urine. Specifically, it's the chemicals that are released when chlorine reacts with urine.
Still ready to take that dip?
How to protect yourself
Some people think a pool that smells strongly of chlorine is a clean pool, but that odor could indicate that contaminants in the pool are not breaking down properly in the presence of chlorine. (Photo: goodluz/Shutterstock)
To protect yourself and your family before you dive into your favorite pool, experts recommend taking a closer look — and smell — of the water. It should be crystal clear and there should be no odor. Any debris that has accumulated either on the surface or at the bottom of the pool is an indicator that this pool is in need of a cleaning. Cloudy water in the pool could be caused by an ineffective filtration system or from a day of overuse (too many sunscreen-slicked bodies diving in and out.)
And while some people might think that a pool that smells strongly of chlorine is a clean pool, that's actually not the case. A strong odor of chlorine could indicate that the contaminants in the pool are not breaking down properly in the presence of chlorine. And if that strong smell coming from the pool is urine, well there is no doubt about what you will be jumping into.
Bottom line: Don't swim if you have diarrhea. Don't pee in the pool. Don't drink and/or swallow pool water. And don't hop in if you're not confident about the cleanliness of the water down below.
Editor's note: This story has been updated with new information since it was originally published in June 2015.