The U.S. Centers for Disease Control reports that outbreaks associated with treated recreational water can be caused by pathogens or chemicals.
During 2000–2014, 493 outbreaks associated with treated recreational water caused at least 27,219 cases and eight deaths. Outbreaks caused by Cryptosporidium increased 25% per year during 2000–2006; however, no significant trend occurred after 2007. The number of outbreaks caused by Legionella increased 14% per year.
The aquatics sector, public health officials, bathers, and parents of young bathers can take steps to minimize risk for outbreaks. The halting of the increase in outbreaks caused by Cryptosporidium might be attributable to Healthy and Safe Swimming Week campaigns.
Outbreaks associated with treated recreational water — United States, 2000–2014
Centers for Disease Control and Prevention
Michele C. Hlavsa, MPH; Bryanna L. Cikesh, MPH; Virginia A. Roberts, MSPH; Amy M. Kahler, MS; Marissa Vigar, MPH; Elizabeth D. Hilborn, DVM; Timothy J. Wade, PhD; Dawn M. Roellig, PhD; Jennifer L. Murphy, PhD; Lihua Xiao, DVM, PhD; Kirsten M. Yates, MPH; Jasen M. Kunz, MPH; Matthew J. Arduino, DrPH; Sujan C. Reddy, MD; Kathleen E. Fullerton, MPH; Laura A. Cooley, MD; Michael J. Beach, PhD; Vincent R. Hill, PhD; Jonathan S. Yoder, MPH