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Summer Time is Swim Time. Enjoy Healthy Swimming by Preventing Recreational Water Illnesses!

May 21-27, 2007 is the third annual National Recreational Water Illness Prevention Week. Many people enjoy water activities such as swimming and visiting water parks to cool off in the heat of summer. But the popularity of recreational water is also associated with public health issues.

Swimming

It is estimated that 7.4 million residential and public swimming pools are in use in the United States and approximately 670,000 pools exist in Canada (1,2). In the U.S., over 360 million annual visits to recreational water venues such as swimming pools, spas, lakes, rivers, and the ocean occur, making swimming the second most popular activity in the U.S. and the most popular activity for children (3).

Interactive fountain
The popularity of waterparks has increased 3-5% in the last 5 years. (CDC Photo)

Waterparks

Growth of waterparks has been substantial in the past 20 years so that currently there are over 1,000 waterparks in North America and 600 more globally. Attendance at North American waterparks in 2004 was approximately 73 million visits (4). However, recreational water use also can be associated with drowning, injury, and the spread of infectious diseases.

Public Health Issues

Recreational water illnesses (RWIs) are spread by swallowing, inhaling, or having contact with contaminated water from swimming pools, spas, lakes, rivers, or oceans (5). The most commonly reported RWI is diarrhea caused by germs such as Cryptosporidium, Giardia, Shigella, and Escherichia coli O157:H7. Children, pregnant women, and persons with compromised immune systems are at greatest risk for infection with these waterborne germs. The spread of RWIs is facilitated by:

  • Chlorine-resistant germs – some germs, like Cryptosporidium, are chlorine-resistant
  • Poorly maintained pools – inadequate disinfection of pools can result in skin, ear, eye, respiratory, wound, and neurologic infections that could be prevented with proper pool maintenance
  • Low public awareness – most people are unaware of RWIs and how they are spread

Improving Prevention Efforts

The emergence of chlorine-resistant germs, poor pool maintenance, and low public awareness about RWIs increases the complexity of any prevention plan. A multi-faceted approach to prevention that targets all of these barriers is essential for decreasing the spread of RWIs. This approach will require a concerted effort to improve operation, training, and public education.

Visit CDC’s Healthy Swimming Web site for further information on RWIs. Additional information for public health professionals, aquatics staff members, and the general public on RWI Prevention Week is also available.

  1. Pool and Spa Marketing. 2003 United States swimming pool market. Hubbard Marketing and Publishing Ltd., Markham, Ontario. Pp 20-21.
  2. Pool and Spa Marketing. 2006 Canadian swimming pool industry. Hubbard Marketing and Publishing Ltd., Markham, Ontario. Pp 39-43.
  3. US Bureau of the Census. Statistical abstract of the United States: 1995. 115th ed. Washington, DC: US Bureau of the Census; 1995.
  4. World Waterpark Association. 2006. Waterpark industry general and fun facts. http://www.waterparks.org/otherArticles/Generalfacts.pdf. (accessed January 6, 2007).
  5. Castor ML, Beach MJ. Reducing illness transmission from disinfected recreational water venues: swimming, diarrhea, and the emergence of a new public health concern. Pediatr Infect Dis J 2004;23:866-70.

Related Information

Healthy Swimming Web site

 

 

Content Source: National Center for Zoonotic, Vector-Borne, and Enteric Diseases (ZVED)
Page Last Modified: October 16, 2007
Page Last Reviewed: May 17, 2007
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