A pilot study to assess the effectiveness of anti-Legionella treatments
Legionella bacteria, pathogenic for man, are the cause of acute respiratory infections referred to as legionellosis*. In France, the disease has been subject to mandatory declaration notification since 1987. The health authorities recorded 1,243 cases of legionellosis** in 2008, including 10% of cases where the patient died. Characterised about thirty years ago, Legionella bacteria have a hydrotelluric origin and are encountered in natural reservoirs (rivers, lakes and ponds), wet ground, compost and waste water treatment sludges. Their optimum growth temperatures are between 25 and 43°C. They consequently colonise numerous systems connected with human activities including domestic hot water systems, jacuzzis, cooling towers for air-conditioning systems or industrial plant, decorative fountains, ice machines, etc. Legionella bacteria are present both in water and biofilms (98%), in the form of microbial colonies which proliferate on the surface of pipes and ducts in contact with water.