Swimming pools - infection control

Cryptosporidiosis is caused by the parasite Cryptosporidium parvum. The parasite is found in the faeces of infected humans, cattle and other mammals.

Outbreaks of cryptosporidiosis associated with pools occur when swimmers accidentally swallow pool water contaminated by the parasite. In 1998, hundreds of people developed cryptosporidiosis after swimming in contaminated public pools in several cities in Australia.

Cryptosporidiosis is very contagious

One infected person can pass enough parasites in a day's visit to contaminate a large swimming pool. The parasites are highly resistant to chlorine, the usual form of pool disinfection. Swallowing as few as two parasites can lead to infection.

Symptoms of cryptosporidiosis

Symptoms develop one to 12 days (on average, seven days) after swallowing contaminated water and include:

• Profuse, watery diarrhoea, often accompanied by abdominal cramping
• Fatigue
• Fever
• Loss of appetite, nausea and vomiting.

The symptoms usually persist for about two weeks, and may be more severe and of longer duration in children, pregnant women and people with a weakened immune system (for example, through HIV/AIDS, chemotherapy or organ transplants). This is due to there being no specific treatment for cryptosporidiosis.

Contamination of pool water

Swimming pools can become contaminated with cryptosporidium as a result of:

• Faecal accidents by infected swimmers. Toddlers (particularly those who are not toilet trained) and children in nappies, underwear or with no bathers are at high risk for accidental faecal accidents in the pool.
• Changing nappies next to a pool.

Preventing the spread of cryptosporidiosis

• To reduce the risk of spreading cryptosporidiosis at public pools:
• Shower yourself and your child before swimming.
• Do not use the pool if you or your child has had diarrhoea or a gastrointestinal infection in the previous week.

Preventing pool contamination by babies and toddlers

To prevent faecal contamination of pool water:

• Do not change your child’s nappy by the side of the pool.
• Dress toddlers in close-fitting swimsuits to better contain faeces.
• Occasionally check their bathers for faecal discharge.
• Reduce the risk of accidents by taking children for frequent trips to the toilet.
• Do not rinse your hands in the pool water after a trip to the toilet or after changing your child’s nappy. Use warm water and soap.

Notify the manager of your local pool if you become sick after swimming

If you or your family develop a gastrointestinal illness after swimming at a public pool, contact the pool manager so that information on any illness trends can be monitored.

Where to get help

• Department of Health’s Environmental Health Unit Tel. (03) 9096 0000
• Your doctor

Things to remember

• Cryptosporidiosis is a highly contagious infection.
• Do not use a pool if you have had gastro or diarrhoea in the previous week.
• Notify the pool manager if you become sick after swimming at a public pool.

You might also be interested in:

• Gastroenteritis - cryptosporidiosis.
  
• Swimming pools - water quality.
  
• Water - tanks, bores and dams.
  

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Department of Health

Last reviewed: September 2011

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<a href="http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Swimming_pools_infection_control?open">Swimming pools - infection control - Better Health Channel</a><br/>
Swimming pools can be infected with cryptosporidiosis, a gastrointestinal infection caused by the parasite Cryptosporidium parvum. It can be fatal in people with a weakened immune system. Cryptosporidiosis is highly contagious and is easily spread when infected swimmers contaminate the pool water with their faeces. With adequate hygiene, pool contamination can be prevented.

Content on this website is provided for education and information purposes only. Information about a therapy, service, product or treatment does not imply endorsement and is not intended to replace advice from your qualified health professional. Content has been prepared for Victorian residence and wider Australian audiences, and was accurate at the time of publication. Readers should note that over time currency and completeness of the information may change. All users are urged to always seek advice from a qualified health care professional for diagnosis and answers to their medical questions.

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