This guide explains what legionella is and what you can do to reduce the risk to you and your family.
Legionella is bacteria commonly found in natural watercourses, such as rivers and ponds. Since legionella bacteria are widespread in the environment, they may contaminate and grow in other water systems, such as cooling towers, and hot and cold water systems.
Water temperatures of 60C and above will kill legionella bacteria. The bacteria can live and multiply in low water temperatures, between 20C and 45C. Legionella is most likely to be found where there is stagnant water and a supply of nutrients, such as rust, sludge, scale, algae or other bacteria.
Legionella bacteria can cause a form of pneumonia called Legionnaires’ disease, as well as other less serious illnesses.
People catch Legionnaires' disease by breathing in air containing the bacteria. The bacteria would not be visible as it can be formed from fine droplets suspended in the air, produced by running a tap or shower, or flushing a toilet.
You can’t get Legionnaires’ disease from drinking water and it can’t be passed from one person to another.
Not everyone who comes into contact with legionella bacteria becomes ill.
Everyone is potentially vulnerable to infection caused by breathing in legionella bacteria, but some people are at higher risk. Those at higher risk include smokers, heavy drinkers, and people over 45 years of age, suffering from chronic respiratory or kidney disease, or a weakened immune system. The symptoms of Legionnaires' disease are similar to the symptoms of flu:
In severe cases, there may also be pneumonia and, occasionally, diarrhoea, as well as signs of mental confusion.
If you suspect that you or someone in your home has contracted Legionnaires’ disease, you should contact your doctor as soon as possible. If your GP diagnoses Legionnaires’ disease, contact us immediately so that water analysis and any necessary treatment of your water system can take place.
The likelihood of legionella being present in your home is very low. Most households don’t store much water and they use water regularly so it’s not standing still in pipes and tanks.
However, there are some simple steps you can take to help prevent the bacteria growing.
The Health and Safety Executive is the government body responsible for water hygiene and Legionnaires’ disease. You can find further advice and information on their website: www.hse.gov.uk/legionnaires