Water Hygiene and Legionella
Legionella and Legionnaires’ disease
This page will provide you with information about the risks associated with legionella bacteria in water systems and the actions you should take to minimise the risk of the bacteria developing within the water systems in your home.
What is Legionnaires’ disease?
Legionnaires’ disease is a potentially fatal form of pneumonia which can affect anybody. The infection is caught by breathing in tiny droplets of water (aerosols) which contain legionella bacteria.
Where can Legionella be found?
Legionella is a bacterium that is naturally occurring in water sources such as rivers, lakes and reservoirs, but usually in very low numbers. Therefore, it is very rare that people contract the disease from this type of water source.
However, as legionella bacteria is so widespread, it can enter domestic water systems and so all hot and cold-water systems in residential / domestic properties are a potential source for legionella bacteria growth.
What increases the risk of Legionella?
If conditions are ‘favourable’ in water systems, the bacteria can grow to dangerous levels, increasing the risk of individuals contracting Legionnaires’ disease. These conditions can be summarised as follows:
- Water at temperatures between 20°C – 45°C
- Water allowed to stagnate (including infrequently used water outlets)
- Deposits present in the water such as scale, sludge, rust etc. which act as nutrients for the bacteria to feed upon and grow
- Situations where breathable droplets of water are created (eg. showers, water outlets, splashing, and flushing toilets).
Who is at risk?
Everyone is susceptible to infection; however higher risk groups of people include those over 45 years of age, smokers, heavy drinkers, people suffering from respiratory or kidney disease and people with an impaired immune system.
However, not everyone who is exposed to the bacteria contracts the disease and Legionnaires’ disease is not contagious between one person and another. In addition, you cannot contract the disease by drinking water.
How do people catch Legionnaires’ disease?
People contract the disease by breathing in tiny aerosol droplets of water which are suspended in the air, which contain legionella bacteria.
The symptoms of Legionnaires’ disease are very similar to flu-type symptoms:
- High temperatures
- Fevers, chills, dry cough
- Headaches, muscle pains
- Tiredness
The disease can be treated with antibiotics prescribed by a doctor.
How to reduce the risk of Legionella
It must be stressed that the risk of legionella causing illness from small domestic water systems is very low. However, we recommend you observe the following simple precautions and good water hygiene practice which will reduce the risk even further:
- Make sure your shower and all water taps are used or flushed through for at least one minute, at least once per week
- For any outlets that have not been used for a prolonged period of time (eg. after you return from a holiday), flush the system through for at least two minutes before use
- Descale and disinfect your showerhead monthly to prevent the build-up of lime scale, mould and algae growth in/on the head
- Always flush the toilet with the lid in the closed position
Keep hot water stored at a minimum temperature of 60°c as this will kill any legionella bacteria. However, please take care with hot water and be aware of scalding risks.
If you are a Newark and Sherwood District Council tenant and your hot water is not heating properly, or you discover any other problems with your heating / water system, please contact our Repairs Call Handling Centre on Telephone 01636 650000 to allow us to take appropriate action.
What to do if you think you may have contracted Legionnaires’ disease
If you or someone in your home develops the symptoms described in this page and you
suspect it may be Legionnaires’ disease, contact your doctor without delay. If Legionnaires’ disease is diagnosed, please inform Newark and Sherwood immediately on the above telephone number.
Please remember
Do not be alarmed, the risk of legionella causing illness from small domestic water systems is very low and can be kept this way by observing the water hygiene precautions described in this page.
You cannot catch Legionnaires’ disease by drinking water. The disease is contracted by breathing in tiny airborne aerosol water droplets which contain legionella bacteria that can be carried for example in mist from a shower.
You can obtain further information and advice on legionella by visiting the Health and Safety Executive’s website at http://www.hse.gov.uk/legionnaires/index.htm