06/06/2012 07:11 BST

Legionnaires Disease Outbreak: Symptons, Causes And Treatment

One man has died and 15 people are in a critical condition in hospital following an outbreak of Legionnaires' disease in Edinburgh. A further 15 people are suspected to have contracted the disease and are also being treated in hospital.

The unusual name for the condition is because it was first identified after a mass outbreak at a hotel hosting a convention of the American Legion organisation. Here are some more facts about the disease:

  • Legionnaires' disease is a potentially fatal lung infection that is caused by the bacteria legionella.
  • The bacteria are commonly found in any freshwater environment such as rivers and lakes but can sometimes find their way into artificial water supply systems.
  • It is contracted when small droplets of contaminated water are breathed in. It cannot spread from person to person.
  • Everyone is potentially vulnerable to the disease but those who may experience a more severe form of infection include the elderly, smokers, diabetes sufferers, those with kidney disease and cancer patients.
  • Legionnaires' disease is three times more common in men than women, and it mostly affects people who are over 50.
  • Symptoms of the disease include headaches, muscle pain, high fever, chills, a persistent cough, shortness of breath, chest pains and sometimes vomiting and diarrhoea.


Legionnaires' disease bacteria under UV light

  • About half of those who contract the disease can experience changes to their mental state, such as confusion.
  • It is estimated that symptoms can start between two and 14 days after exposure to the infection.
  • The disease is treated by intravenous antibiotics.
  • An estimated 10% of people who contract legionnaires' disease will die from complications arising from infection.
  • Large buildings such as hotels, hospitals and museums are more vulnerable to legionella contamination because they have larger, more complex water supply systems, which can let the contamination spread quickly.
  • There are strict regulations regarding the maintenance and control of water supply systems, such as either keeping the water cooled below 20C (68F), or heated above 60C (140F), in order to prevent an outbreak of Legionnaires' disease.

Information from NHS online.