1. Legionnaires’ disease is a severe type of pneumonia, an infection that causes inflammation of the air sacs in the lungs. The sacs fill with liquid, making it difficult for the lungs to transport oxygen around the body in the blood.
2. Legionnaires’ is caused by the legionella bacterium, which infects people when they inhale tiny droplets from a contaminated source.
3. People infected with the legionella bacteria typically become ill two to 14 days after exposure. Early symptoms are flu-like and include muscle aches, tiredness, headaches, dry cough, chest pains, shortness of breath, confusion and fever.
4. In some people, usually those with weakened immune systems, the disease can be fatal. Most deaths occur in people who are aged 70 or older.
5. Legionnaires’ can lead to life-threatening complications including organ failure and septic shock. An estimated 10% of otherwise healthy people who develop Legionnaires’ disease die due to such complications
6. Legionella bacteria grows in warm water, usually between 20-45C. It can be found in harmlessly low numbers in ponds, rivers and lakes, but will multiply rapidly in artificial water supply systems such as air conditioning systems.
7. The bacteria is only a risk to health when the water temperature allows it to multiply rapidly, often in water systems which aren’t properly designed, installed and/or maintained.
8. Large buildings such as hotels, hospitals and office blocks, are more vulnerable to legionella contamination because they have larger, more complex water supply systems in which the bacteria can quickly spread.
9. Although rare, Legionnaires’ disease has also come from contaminated showers, sprinkler systems and spas.
10. The disease is treated with antibiotics, usually for about three weeks. Around 90% of people with Legionnaires’ make a full recovery after taking antibiotics.