Anyone with a gastrointestinal infection or diarrhea should only enter a hot tub after two weeks. The reason for this is because that is the time taken for the body to recover and stop shedding bacteria related to diarrhea. You can make others sick if this water is swallowed because millions of bacteria will enter the water thanks to you. The biggest prevention, in this case, is to keep your head above water at all times.
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Cryptosporidium is a bacterial parasite that tolerates chlorine and can easily survive in a hot tub. It can cause diarrhea lasting for weeks and has no cure so if you contract it you just have to manage it till the disease runs its course.
Crypto is passed through feces and can even result in death. The bacteria in hot tubs is chlorine tolerant and can withstand chemicals for days.
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