That's why it's important to take that extra second to check out the pool, and your own hygiene before you jump in.
The water-borne infection is known as Shigellosis.
The bacterial illness spreads person to person, hand to mouth, and most commonly, poor hygiene with young children.
It's hard to resist a swimming pool when it's so hot. You want to cool off, but you don't want to catch a nasty bug.
Shigellosis is known for being an extreme case of stomach flu. To prevent the infection, washing your hands, and showering before you hit the pool deck can keep yourself and others safe.
Marci Shaw, a Health Specialist at the Vigo County Health Department said, "Especially with small children, make sure you're washing their hands well. Because sometimes they don't always do a great job themselves."
But pools aren't the only areas where this infection can spread.
"Contamination from day care centers and things like that are more common, especially with small children. Sometimes they can probably have it through contaminated water, so streams or pools that don't have the right amount of chlorine in them could be a source," said Shaw.
Indianapolis has seen 160 cases already this summer, and Vigo County wants to make sure it doesn't make its way to the Valley.
"If you have the means of checking the pool to make sure the chlorine is the right level, that would be your first step. Also, don't get in the pool if you've had diarrhea in the last couple weeks. That protects you and protects others," said Shaw.
Pool experts say, even if you're pool water is clear, check the chemical levels to be safe. The minute the water becomes hazy, that's a hint that bacteria is growing.
Sonja Camacho, the Assistant Manager of Fun-N-Suns Pools said, "Kids are going to jump in anyway, so I mean usually no matter what that pool looks like. Make sure the pool is clear and they have checked the chemicals."
Shigellosis can also be a problem in winter time. But with all the public and private pools open right now, people need to take the extra precautions before making a splash.
Anti-biotics can usually treat the bacterial infection, but it's important to know that Shigellosis can be deadly.
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