What is Legionella?

Legionella are bacteria found in natural water systems that can cause illnesses like Legionnaires’ disease. The disease is contracted by inhaling contaminated water droplets (aerosols) from artificial water systems where the bacteria have multiplied.

Causes
Legionella grows best in water temperatures between 20°C and 45°C. Stagnant water and the presence of rust, sludge, and scale provide nutrients for the bacteria to thrive.

Common sources

• Air conditioning and cooling towers
• Hot and cold water systems, particularly in large buildings
• Hot tubs, spa pools, and whirlpools
• Showers and taps that are not used regularly
• Humidifiers and decorative fountains
• Soil and potting mix, which can contain a specific strain of Legionella

Illnesses Caused by Legionella

Legionella bacteria cause a group of illnesses called legionellosis.

Legionnaires’ Disease
A serious, potentially fatal type of pneumonia. Symptoms are similar to the flu but can progress to severe breathing difficulties, chest pain, and mental confusion.

Pontiac fever
A milder, flu-like illness that typically goes away on its own. Symptoms include high temperature, chills, and muscle aches.

Legionella Testing Programme