Healthy Swimming Pools

Last updated: 01 November 2007

To protect others, don't swim if...

...you have diarrhoea for at least a week after it has completely cleared up.

...you have cryptosporidiosis or germs like E.coli, shigella and viruses, which are transmitted through the faecal-oral route. They are highly contagious and spread by people accidentally swallowing pool water that has been contaminated. This causes people to be sick with symptoms such as diarrhoea, nausea, vomiting, abdominal cramps and fever.

'Crypto' can survive in a swimming pool for weeks thereby infecting swimmers and causing large disease outbreaks. It is therefore vital that swimmers don't introduce the bug into pools in the first place.

Other problems that can affect pools

'Swimmers itch' which is caused by Pseudomonas aeruginosa. This organism is responsible for skin (follicle) and mucous membrane infections and ear infections, particularly in kids, which tend to be difficult to treat. The organism proliferates very quickly in pools when the water temperature is greater than 26C and when disinfection levels are not maintained at all times. This organism also causes outbreaks in heated spa pools.

Legionella can also be a problem in poorly maintained heated spa pools. Home heated spa pools are much more popular these days.

Outbreaks

NSW Health has seen large infectious outbreaks of people suffering from diarrhoea every few years, mainly due to the presence of cryptosporidiosis in swimming pools. The last outbreak involving thousands of cases across NSW was in 1998.

These outbreaks may occur cyclically because people probably develop short-term immunity to 'crypto'. This means that NSW is probably due for more cases of infection this year unless we can all do our bit to protect backyard pools and community pools from contamination.

Looking after our pools

The good news is that most of these germs are killed by chlorine, the most common chemical used to disinfect pool water. Giardia is a form of bacteria that can survive for some time in chlorinated pool water. However, cryptosporidium is resistant to chlorine and is so small in size that it can slip through pool filters.

Pool owners should double check that their pools are correctly maintained and clean throughout summer. If a pool's chlorine, pH levels or other disinfection system are not maintained properly, the chemicals cannot do their job properly. It is therefore crucial for pool owners to regularly adjust chemicals when needed. Pool filters should also be carefully maintained to ensure they are working properly.

How to stay safe and healthy

Unfortunately even the best maintained pools and chemicals alone won't keep a pool safe. A person who has had recent diarrhoea can easily contaminate a backyard swimming pool or local community pool.

There are some key things that everyone can do to keep their backyard pool and their local community pool healthy:

• Don't swim if you have diarrhoea or have suffered from diarrhoea within the past week
• Don't swallow the pool water and try not to let water into your mouth
• Wash your hands with soap and water after using the toilet
• Don't allow pets in the pool.

Parents have a key role to play in ensuring pools remain safe for everyone by ensuring that non-toilet trained children do not have toileting accidents in the pool.

Young children and others who are likely to have toileting accidents should avoid sharing pools with others. Parents with young children should make use of disposable 'swimming' nappies which are available from most supermarkets or they can put their babies and young children into tight fitting swimmers.

While swimming nappies and tight swimmers won't stop the water being contaminated, they will help clean up of pool should the child have an accident.

Parents can also do the following things to avoid pool contamination:

• Take their child on bathroom breaks often rather than waiting to hear they 'have to go' as it may be too late
• Change nappies in a bathroom and not at the poolside as germs can spread to surfaces or objects in and around the pool and spread illness
• Wash their child thoroughly (especially on the bottom) with soap and water before going swimming
• Wash their hands with soap and water after changing a child's nappy.

More health and safety tips

• Pool filters should be operated at least 8-12 hours per day depending on pool use.
• People shouldn't use glassware or electrical appliances around pools.
• Pools should be properly fenced, gates not propped open or broken, kids supervised and a resuscitation chart displayed.
• People shouldn't consume alcohol and then soak in a heated spa bath. The blood vessels dilate and venous pooling can occur resulting in fainting and drowning.

Related links

• Swimming Pools and Spa Pools  http://www.health.nsw.gov.au/PublicHealth/environment/water/water_spa.asp