Legionella management relies on frequently treatment and assessing of sources which might be prone to offer favorable conditions for the Legionella bacteria to reproduce. For harboring Legionella training, the most frequent sources, are cooling towers, industrial sized air conditioning systems, domestic hot water systems, fountains, swimming pools and whirlpool hot tubs. The Legionella bacteria can also be naturally present in little amounts in pools, streams, rivers, lakes and reservoirs.
Legionnaires disease is spread when the bacteria is suspended in droplets of water and taken by the wind or through a buildings air conditioning system. Results of evaluations with a French team of scientists found that Legionella management that has been inferior could lead to the bacteria being taken up to 6Km by the wind. In 2003-2004 an instance in Pas de Calais had 18 deaths and 86 confirmed cases. It had been found the furthest known cases were up to 6Km from the site and that the origin of the outbreak were the cooling towers of a petrochemical plant. The European Working Group for Legionella Infections (EWGLI) was set up as a reply to the situation and created a group of principles and courses of action that company’s were obliged to follow in order to carefully track potential sources of Legionella training. The EWGLI urges that temperatures leave them improbable to multiply or above 50 degrees Celsius will kill the bulk of bacteria. Temperatures between 45 degrees and 35 degrees Celsius Celsius is where the best reproduction of the bacteria takes places and anything from 20 degrees Celsius to 50 degrees Celsius is when development occurs. Any temperature below 20 degrees Celsius the Legionella bacteria can live but will likely be dormant.