Recreational water illnesses (RWIs) are a problem in the US and abroad. This is the CDC's latest surveillance summary of RWIs that occurred during 2006-2006. Keep in mind most RWIs are under-diagnosed and under-reported in the US, so the actual number of cases is probably much higher.

One of the best ways to prevent RWIs is to educate yourself. Visit the CDC healthy swimming website for more information at
http://www.cdc.gov/healthyswimming/what.htm