Legionnaires' Disease

Legionnaires' disease is a potentially fatal form of pneumonia which can affect anybody, but which principally affects those who are susceptible because of age, illness, immunosuppression, smoking etc.  People catch Legionnaires' disease by inhaling small droplets of water suspended in the air, which contain the bacteria Legionella pneumophila.  Usually spread is by inhalation of aerosols created by any type of water spray such as showerheads, water flumes, certain types of air conditioning system, spa pools etc.

The initial symptoms of Legionnaires' disease are similar to those of flu and include high temperature, fever and chills, cough, muscle pains and headache.  Legionella is present in the environment and most healthy people who are exposed to it do not become ill. Legionnaires' disease does not spread from person to person. 

Typically risk are created as a result of poorly maintained water systems.  Certain conditions increase the risk from Legionella:

  • a suitable temperature for growth, 20 to 45oC;
  • a source of nutrients for the organism, e.g. sludge, scale, rust, algae, and other organic matter; and
  • a way of creating and spreading breathable droplets.

Within the University, Estates and Buildings and Residential Services are responsible for the maintenance of most of our water systems.  However, other management units may also operate specialist systems such as flumes, swimming pools etc.  All units who operate water systems should identify these systems and ensure the risk from Legionella has been assessed and suitable maintenance regimes established.  This may require assistance from a contractor.

Regular use of all taps and water outlets to allow flushing of pipes and frequent cleaning of items such as showerheads will reduce the risks significantly.  In particular, showerheads (including emergency showers) that are used infrequently may require dismantling, cleaning and disinfection on a periodic basis to ensure that risks are managed in accordance with best practice.  Units who have such equipment should establish systems for this.

Further advice can be found on the HSE Legionnaires' Disease microsite.   This includes an Approved Code of Practice that can be found within the "Resources" section of the site.