As one indication of how far the industry still has to go in efforts to prevent recreational water illnesses, the Centers for Disease Control and Prevention reported in September a 72 percent increase in outbreaks over the previous two-year tally — and the largest number of such outbreaks ever recorded for a two-year span.

The report, which received a significant amount of media attention, shows that from January 2007 through December 2008, 134 recreational water illness outbreaks were reported in 38 of the 50 states and Puerto Rico. That included 12 outbreaks in Minnesota, 11 in Florida and eight in New York. By comparison, 2005-06 saw 78 outbreaks in 31 states. The median number of individual cases linked with an outbreak was 11.

The biggest driver of the increase was the parasite cryptosporidium. Finalized data, compiled from reports by state health agencies, indicates that nearly half the outbreaks were caused by crypto, which can cause severe stomach and intestinal issues. Complete findings and analysis are detailed in two Morbidity and Mortality Weekly Report Summaries, available online.

Including the crypto cases, more than 13,966 documented cases of RWIs were recorded for the 2007-08 period. Eight of those victims died, though all from fresh water-related illness. In the previous two-year span, 4,412 people were sickened, with five eventually dying, all from treated water settings.

“We really try to emphasize that there are three stakeholders,” said epidemiologist Michele Hlavsa, chief of the CDC’s Healthy Swimming Program, referring to aquatics facility operators, public health officials and the swimming public.

Treating crypto requires operators and public health officials to do their part, but because crypto is not killed via regular chlorination, patrons also need to be aware of safe swimming behaviors.

Hlavsa also noted that of the 134 outbreaks, 116 (approximately 85 percent) were linked to treated water and almost 50 percent of the 116 were associated with settings where recreation is not the primary focus, such as apartment complex pools. That indicates aquatics professionals need to focus more attention on improving pool operation in those types of facilities, she added.

National media outlets, including ABC News and WebMD, reported the 2007-08 statistics and data for 2009-10 are expected to be released in the next year.