History:  Concerns with an E. coli waterborne disease outbreak this last summer on the east coast coupled with reported outbreaks of Cryptosporidium and Legionella associated with pools have heightened interest surrounding pool contamination. The public, pool operators and health departments must develop a higher standard of care to protect against potential waterborne illness outbreaks.  This guidance document is developed to assist the operator and inform the public of waterborne risks.

In general, responsible pool operators have provided well-maintained pool facilities, which will help to eliminate many of the problems related to waterborne illness.  Some of the illnesses have very severe symptoms and it takes relatively few organisms to cause the diseases [E. coli O157:H7, Shigella]. Other organisms are very resistant to disinfection [Cryptosporidium].  It is important to inform the public of potential risk factors and provide education on proper means to help prevent potential illness.                                                                                             

Because some organisims are resistant to standard disinfection levels established for pools, there is no absolute assurance that the pool could not become a source of potential contamination.  Fortunately, the potential for illnesses can be reduced when operators establish good operating practices and bathers are aware of the risks for causing and contracting illnesses.

Recommendations:  There is general agreement amongst local health jurisdictions that water recreation facilities need to assure the following:

• Minimum disinfectant levels need to be maintained vigilantly at all pool facilities.
• The public needs to be cognizant of the potential risk for infecting other individuals if they have suffered a communicable illness, even though they no longer have symptoms. (In general, it is recommended that persons that have been ill not use a public pool within two weeks of suffering an illness. Symptoms of concern include fever, diarrhea, vomiting, nausea, abdominal cramps, upper respiratory infections, staphylococcal or pseudomonas skin infections, and conjunctivitis.)
• Infants, small children and other incontinent users need to wear tight-fitting, waterproof liners around diapers. Some facilities are now providing such plastic, rubber or vinyl pants at their facility.
• Schedule special sessions for pool use by incontinent pool users [e.g. infant swim classes] to reduce the number of people who may be potentially exposed. Avoid scheduling high use activities immediately after incontinent people use the pool.
• Operators should increase disinfectant levels during the time period the incontinent persons use the pool e.g. during infant swim periods (the maximum allowed is 6 ppm for a swimming pool and 10 ppm for a spa pool).
• Immediately use procedures outlined in pool contamination guidance documents if visible contamination has occurred in the pool water.
• Encourage people to take hot soapy showers in the nude prior to entering the pool.
• Assure proper operation of the recirculation treatment system for the facility.
• Provide safe and accessible diaper-changing areas. Do not allow diaper changing at poolside.
• Provide training for staff on potential illness issues to increase their awareness and ability to provide better information to the users on potential risks and the need to provide good hygiene.
• Reinforce to users not to purposely drink pool water to help reduce the risk of contracting gastrointestinal illnesses.
• If problems are noted with visible body contaminants in the pool, notify the pool operator immediately and follow the instructions in the pool contamination guidance document for cleaning the pool.

Pool facility owners and operators can provide additional protection by controlling use of pools by incontinent users. Some may prefer exclusion while others may want incontinent users to provide additional protection to the pool by requiring tight-fitting waterproof pants. Realistically, all bathers will add some level of contamination to the pool and good hygienic practices need to be followed by all.