Swimming pool water and illness
Most swimming pools are clean. But sometimes, particularly if a pool is very busy or hasn't been properly treated with pool chemicals, germs can multiply.
Germs in swimming pools can cause illnesses like infections of the ear, eye, skin and chest, as well as gastroenteritis. Also, strong chemicals in pool water can sometimes cause eye and skin irritations.
In this article, we use 'swimming pools' to include public or private swimming pools, hydrotherapy pools, hot tubs and spas, inflatable and wading pools, and water parks.
How do germs get into swimming pools?
Germs can get into pool water through:
- skin, sweat, wee, poo, saliva and open sores
- dirt, food and other solids that end up in the pool.
This can happen quite easily. For example, if you've had diarrhoea, germs can still be on your skin even if you've cleaned your bottom and hands really well. So if you get into a swimming pool, germs can go from your skin into the water.
Also, babies or non-toilet trained children are very likely to poo in the water when they're swimming. If they've had runny poo, germs from their poo can get in the water, even if they're wearing a swimming nappy. Or if you change a sick child's nappy near a swimming pool, germs from the nappy can get into the water even if the child doesn't.
Swimming pool hygiene: keeping pools clean and safe
Here are some simple tips to help keep swimming pools fun and safe for everyone.
For all swimmers
- Don't get in the pool if you have diarrhoea, or have just gotten over diarrhoea.
- Try not to get water in your mouth, and don't swallow pool water.
- Wash your hands with soap and water after using the toilet or changing a nappy.
- Shower before you get in the pool and when you get out.
For parents of young children
- Make sure your child has a clean bottom before your child gets into the pool.
- Use well-fitted swimming nappies to help stop poo from getting into the water, but note that these nappies aren't leak proof. They can delay but not stop the germs getting into the water.
- Change swimming nappies regularly to stop nappy contents getting into the water.
- Keep nappy changes away from the pool area. With lots of water splashing about, it's easy for germs to end up in the pool.
- For toilet-trained children, try to prevent toilet accidents in the pool by making sure your child has regular toilet visits.
It's recommended that children under 16 years should stay out of spas. The germ risk from spas is too great for young immune systems.
Keeping home swimming and wading pools clean
Because home wading pools are mostly used by babies and young children, they're most likely to have germs that come from poo. Also wading pool water isn't usually treated with pool chemicals.
You can reduce the risk of your young child getting sick from using a wading pool by:
- trying to keep pool water out of your child's mouth - young children are more likely to swallow pool water than other swimmers
- always emptying the wading pool at home once you've finished using it. Leaving water in the wading pool is a drowning risk as well as a germ risk.
Home swimming pools need regular treatment and monitoring to keep them clean and safe for swimming. You can start by:
- using pool chemicals strictly according to manufacturer's instructions
- testing the water's pH and chlorine levels regularly
- checking that the water is clear and that you can see the bottom of the pool.
You can get advice about swimming pool hygiene from pool chemical suppliers or pool maintenance companies, as well as the Environmental Health Officer at your local council.
If there's a poo accident in your pool, get everyone out straight away. If it's a wading pool, empty the water out and scrub the pool with disinfectant. Rinse the pool and then dry it in the sun for at least four hours before using it again. If it's a swimming pool, follow the cleaning and treatment instructions that come with your pool chemicals.
Staying healthy in public swimming pools
If a public pool has been properly treated with pool chemicals, most germs in the pool will be killed.
But when a public pool is very busy - for example, on a hot summer day - germs can get into even the cleanest pool. More people mean more germs and more dirt in the water.
If you want to know how clean and safe a pool is to use when it's busy, ask the pool staff about the latest pH measurement. They should be able to explain it to you.
If there's a poo accident in a public pool, get out and let the pool staff know straight away. If you or your child gets sick after using a public pool, contact the pool staff so they can monitor potential disease outbreaks.