Cryptosporidium, a microscopic parasite that can cause nasty gastrointestinal illnesses, has been increasingly found in recreational waters and appears to be growing resistant to antibacterial cleaners and disinfectants.
Also known by its shortened version Crypto, the parasite is currently the leading cause of waterborne illness in the United States and can also be found in
contaminated food, according to Newsweek. There are reportedly 20 different species of Crypto but only a handful can harm humans.
"In the past two decades, there has been a substantial increase in the number of (recreational water illness) outbreaks
associated with swimming," according to the Centers for Disease Control and Prevention website. "Crypto, which can stay alive for days even in well-maintained pools, has become the leading cause of swimming pool-related outbreaks of diarrheal illness. From 2004 to 2008, reported Crypto cases increased over 200 percent."
The CDC wrote that Crypto is protected by an outer shell that allows it to survive outside the body for long periods of time and makes it tolerant to chlorine disinfection. The parasite can also be found in drinking water as well as recreational water.
"Although Crypto is tolerant to chlorine, most germs are not. Keeping chlorine at recommended levels is essential to maintain a healthy pool," the CDC website noted. "However, a 2010 study found that one in eight public pool inspections resulted in pools being closed immediately due to serious code violations such as improper chlorine levels."
Michele Hlavsa, an epidemiologist with the
CDC's Healthy Swimming program, told Live Science that one of the reasons for the Crypto outbreak could be that people are reporting it more because of improved awareness to swimming-related illnesses.
"People are realizing it's not necessarily only about where they ate or what they ate," Hlavsa told Live Science. "It could be about where they went swimming."
The CDC is recommending that people shower before entering the pool and take their children on frequent bathroom breaks. The agency is also asking people who have suffered diarrhea to stay out of pools for two weeks after it stops if they were previously diagnosed with Crypto.