What is the ideal growth temperature for Legionella pneumophilia bacteria?

Legionella pneumophila, the bacterium responsible for Legionnaires' disease, thrives best at a temperature of around 37 °C. This temperature coincides with the typical body temperature of humans, making it an ideal environment for the bacteria to grow, particularly in water systems such as cooling towers, hot water tanks, and air conditioning systems.

At this temperature, Legionella can replicate rapidly, increasing the risk of exposure to humans. Understanding the optimal growth temperature is crucial for effectively managing and controlling outbreaks, as maintaining water temperatures even slightly below or above this range can inhibit bacterial growth, thereby reducing the risk of infection.

Temperature settings in water systems are therefore critical to controlling the presence of Legionella; keeping temperatures below 20 °C can prevent its proliferation, while maintaining temperatures above 60 °C can kill the bacteria. Hence, recognizing 37 °C as the optimal growth temperature allows for better risk assessment and management in facilities where Legionella may pose a threat.