Outbreaks caused by the parasite Cryptosporidium, which is often seen in swimming pools, have more than doubled from 2014 to 2106, CDC researchers reported.
Writing in the Morbidity and Mortality Weekly Report, the authors said that at least 32 outbreaks caused by "Crypto" were reported to the CDC in 2016 compared to 16 outbreaks just 2 years prior. Crypto infection causes diarrhea, cramps, nausea and vomiting. The authors said the parasite can potentially spread when a sick person has diarrhea and it spreads to pool water, where other people swallow it. They characterized "Crypto" as the most common cause of diarrheal illness linked to swimming pools and water playgrounds because it is not killed by chlorine and can survive for up to 10 days in pool water.
Sick children and adults should not swim while they have diarrhea and those swimming should not swallow pool water in order to prevent spread of the infection, researchers said.