Armchair microbiologist Rick Ledbetter with the Salt Lake County Health Department says that to avoid Cryptosporidium in pools, “Wash your bum! Use plenty of soap, scrub down thoroughly. If you’re a mom of little children, use diapers, wash their bum and make sure you wash your hands before you come back to the pool so again we’re not spreading germs.”

Salt Lake County battled an outbreak of cryptosporidium in 2007 and a spike in cases in 2012. Health officials say it can be easily prevented — if swimmers practice proper hygiene before diving into the pool.

At the Redwood Recreation Center, the pool is closed for five minutes every hour to encourage people to take a bathroom break, rather than going in the pool. Every other hour, the water is tested for bacteria.

The pool’s manager, Avonte King-Henry, said they’re vigilant about germs, knowing how fast crypto can spread.

“Super fast, especially with diarrhea,” he said. “That cloud that happens, it just spreads so fast. It’s so important to get them out and close the pool off.”