Legionnaires' Disease
Please select a letter from the A-Z list below:
Legionella is a bacterium which can lead to
legionellosis illnesses, most commonly a serious and potentially
fatal type of pneumonia known as ‘Legionnaires’ disease.
Other similar (but usually less serious) conditions include Pontiac
fever and Lochgoilhead fever.
How can infection occur?
Infection is caused by breathing in tiny
droplets of water (an aerosol) contaminated by the bacteria. The
disease cannot be passed from one person to another.
Everyone is potentially susceptible to
infection but some people are at higher risk, e.g. those over 45
years of age, smokers and heavy drinkers, those suffering from
chronic respiratory or kidney disease, and people whose immune
system is impaired.
Legionella bacteria are common in natural
water courses such as rivers and ponds. Since legionella are
widespread in the environment, they may also contaminate and grow
in other water systems such as cooling towers and hot and cold
water services.
They survive low temperatures and thrive at
temperatures between 20-45°C if the conditions are right, e.g. if a
supply of nutrients is present such as rust, sludge, scale, algae
and other bacteria. Hence stored water poses the highest risk. The
bacteria are killed by high temperatures.
There are no cooling towers at the University
and water is supplied direct from the mains, this minimises the
risk of infection.
The water distribution systems across the
campus including the control of legionella are managed by the
Estates Office.
However, there are other places where
legionella can grow. Water in car windscreen reservoirs for
instance can provide an environment for legionella bacteria to grow
and hence enter car interiors in a fine mist when sprayed. Using
screenwash in the correct concentrations will protect against
this.
HSE Information and Guidance on Legionella
risk management: