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 recommend closing pools and treating the water with high levels of chlorine, known as hyperchlorination when diarrheal incidents or crypto outbreaks occur in a swimming pool or water playground.
It only takes a mouthful of contaminated water to make a healthy person sick for up to three weeks.
There were 12 cases in 2014, 53 cases in 2015 and 21 cases in 2016.
OH experienced a almost fivefold increase in cryptosporidiosis cases in 2016, with 1,940 reported cases compared with an average 399 cases during the prior four years. Any inadvertent ingestion of even chlorinated pool water could wind up giving you cryptosporidium. It is also warning parents not to change diapers near a pool, but Conrad said there is something else people are forgetting.
With temperatures warming up, more Canadians will be flocking to public pools - they're the flawless catalyst for an outbreak, he warned.
According to one report, the reported prevalence of cryptosporidium among patients with gastroenteritis is 1% to 4% in Europe and North America and 1% to 37% in Africa, Asia, Australia, and South and Central America.
Hlavsa said crypto is resistant to chlorine.
Crypto can survive up to 10 days in even properly treated water.
The only way to get rid of Crypto in a pool is to shut it down and hyper-chlorinate it.
Alabama, Arizona, Ohio, and other states examined and controlled outbreak of Crypto connected to swimming pools or water playgrounds in the year 2016.
A second report in the MMWR noted another potential hazard of public pools - inhalation of toxic chlorine gas. In 2014, there were 16 outbreaks, according to data published by the CDC's Morbidity and Mortality Weekly Report on Thursday.
Healthy swimmers should avoid swallowing any water and rinse off after each dip, the agency says.
Michele Hlavsa, the chief of the CDC's Healthy Swimming Program, reminded parents to be cautious when taking their kids out to swim. Pool operators and staff must be trained in pool chemical safety as well as appropriate operation and maintenance of equipment.
That last tip is important not just for preventing pooping accidents, but for keeping kids from urinating in the pool.