Researchers have identified Cryptosporidium as a leading culprit responsible for disease outbreaks at pools, water parks, or other venues with treated water.
Data from the Centers for Disease Control and Prevention’s (CDC) Waterborne Disease and Outbreak Surveillance System show that 28 states and Puerto Rico reported 81 water-borne disease outbreaks at recreational venues during 2009 to 2010. Of 57 outbreaks linked with treated water, Cryptosporidium caused 24.
Treated Water in Pools, Parks Hides Disease-Causing Cryptosporidium. JAMA. 2014;311(9):895. doi:10.1001/jama.2014.801