Legionella spp.
Legionnaire’s disease is a potentially fatal form of pneumonia caused by the bacterium Legionella pneumophila. This bacterium exists naturally at low numbers in environmental water sources e.g. lakes, rivers and reservoirs, however it presents a major problem when given the conditions for proliferation to high numbers. Legionela bacteria grow at temperatures ranging from 20° C – 45° C; however it has been seen to survive at temperatures to the extreme of these (Rogers et al., 1994).
Legionnaire’s disease is transmitted by inhalation of water droplets containing the bacterium. Outbreaks occur from exposure to Legionella growing in built systems which provide a suitable temperature for growth and the opportunity for infection by generation of aerosols containing Legionella e.g. showers, cooling towers, spa pools and hot water systems.
Rogers, J., Dowset, A.B., Dennis, P. J., Lee, J. V. & Keevil, C. W. (1994). Influence of Temperature and Plumbing Material Selection on Biofilm Formation and Growth of Legionella pneumophila in a Model Potable Water System Containing Complex Microbial Flora App & Env Microbiol. 60, 5 1585-1592.
Please see CLS Legionella Risk Assessment Page