Swimming is a popular low-impact activity that is a great way to stay active and maintain good health and fitness. Pool managers treat and maintain water quality in swimming pools to keep swimming pools clean. There are simple things we should all do to help keep the pool clean. With good hygiene and healthy swimming practices, we can all help prevent contamination and swimming pool-related illnesses.
Swimming is a popular low-impact activity that is a great way to stay active and maintain good health and fitness. Swimmers should be aware that while pool managers treat and maintain water quality in swimming pools to keep swimming pools clean, there are simple things we can all do to help keep the pool clean. With good hygiene and healthy swimming practices, you can help prevent contamination and swimming pool related illnesses.
Germs such as bacteria, viruses and parasites may be present in swimming pools and other recreational water bodies when contaminants are brought into the water. You share the pool water with everyone and practising good hygiene before going swimming can prevent germs on swimmers’ bodies from contaminating pool water.
Most pools have treatment systems in place to kill germs. Depending on the type of germ and how long it takes for the germ to be killed, sometimes visitors can get sick when they come in contact or swallow small amounts of contaminated water.
Keep germs out of pool water
We all have germs on our bodies which can wash off and contaminate the pool water. We are more likely to carry germs that can make others sick when we are not feeling well.
For example, if you have a stomach upset and diarrhoea, there are thousands of germs in your faeces (poo) and traces on your bottom. These germs wash off and contaminate the pool when you go swimming.
To keep germs out of the pool, you must not go swimming when you have diarrhoea. If you have been diagnosed with an infection called cryptosporidiosis (crypto), then you must not swim for 14 days after the diarrhoea stops. If you have diarrhoea and are unsure of the cause, do not swim for 14 days after the diarrhoea stops.
Chlorine kills germs over time
Chlorine is able to kill most germs, but it doesn’t happen straight away. Some germs such as Cryptosporidium can live in pool water for days. Without your help, even the best maintained pools can spread germs.
How long to stay out of the pool
If you have any of the listed infections, you need to stay out of swimming pools for the recommended times, which are:
- Chickenpox – avoid swimming for seven days after the rash appears.
- Cryptosporidiosis (crypto) – do not swim for 14 days after diarrhoea stops.
- Tinea corporis (athletes foot) – do not swim until a day after treatment is started.
Cryptosporidium is a parasite
Cryptosporidium is a tough germ that can be spread when recently infected swimmers contaminate the water with tiny amounts of the germ present on their body. Cryptosporidiosis (crypto) is the disease caused by the germ and possible sources of contamination include someone who has recently had the illness, domestic animals such as pets, and farm animals such as cattle.
Cryptosporidium lives in the bowel and is found in the faeces (poo) of infected humans. The germ is normally spread through poor hygiene (such as not washing), usually by ingestion of contaminated foods or water.
Outbreaks of crypto associated with pools occur when swimmers accidentally swallow pool water contaminated with the germ.
Cryptosporidiosis is very contagious
One person infected with crypto can pass enough germs in a single visit to contaminate a large swimming pool. The germs are highly resistant to chlorine, the usual form of pool disinfection. Swallowing as few as two of the grems can lead to infection.
Symptoms of cryptosporidiosis
The symptoms of crypto are usually mild, but illness can be more severe for people with impaired immunity, in children and pregnant women. After infection, it can take one to twelve days (on average seven days) before you become ill.
Symptoms may include:
- profuse diarrhoea, often with abdominal cramping
- loss of appetite, fatigue, nausea and vomiting.
To prevent further spread of crypto, it is important for any swimmers who have had crypto not to swim for two weeks after diarrhoea stops. There is no treatment for crypto. Consult your doctor for medical advice.
Preventing Cryptosporidium contamination of swimming pool water
Poor hygiene practices mean that most swimmers retain some faeces on their body. This can be rinsed into the pool while swimming.
To help prevent contamination of pool water, you should:
- Never swim in a pool if you have diarrhoea or if you have had diarrhoea in the past two weeks.
- Shower and wash thoroughly with soap (especially your bottom) before entering the pool.
- Wash your hands with soap after going to the toilet or changing a nappy.
- Change nappies in nappy change areas only.
- Avoid swallowing pool water.
Preventing pool contamination by babies and toddlers
Babies and toddlers are still training to control their bowel movements, so parents and supervisors should be extra careful to prevent faecal accidents and contamination of pool water.
To prevent faecal contamination of pool water:
- Keep an eye on your children at all times.
- Take children on frequent toilet breaks every hour or check nappies every 30–60 minutes.
- Change nappies in nappy change areas only.
- Do not change nappies by the poolside.
- Non-toilet trained children should wear tight-fitting waterproof nappies.
- Report any faecal accidents to swimming pool staff.
Notify the pool manager of sickness
If you or your family develop a gastrointestinal illness after swimming at a public pool, contact the pool manager so information on any illness can be monitored.
Where to get help
- Your local swimming pool
- Department of Health Water Program Tel. 1300 761 874
- Your doctor
- Your local council
Things to remember
- You can help keep your pool clean by following simple steps to healthy swimming.
- Do not swim if you have diarrhoea.
- Cryptosporidiosis is highly contagious. Do not swim for 14 days after diarrhoea stops.
- If you have diarrhoea and are unsure of the cause, do not swim for 14 days until after diarrhoea stops.
- Notify the pool manager if you become sick after swimming at a public pool.
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Last reviewed: March 2015
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