Prevalence of Legionella Pneumophila in Production Networks and Distribution of Domestic Hot Water in Morocco

The goal of this study was to evaluate the prevalence of Legionella pneumophila specie in hot water samples from tanks and ecological networks of production and distribution of domestic hot water in Morocco. To accomplish this study, 156 samples of hot water, were collected from thirty four structures' from January 2009 to December 2010, were analyzed to search and enumeration of Legionella pneumophila by culturing onto a selective medium. The results of all samples showed that Legionella pneumophila was detected in 31.5% of total samples analyzed 67.4% with a load above the limit tolerated by the regulations. The serological survey showed that 37% of isolates are Legionella pneumophila sero- group 1 while 63% correspond to serogroup 2-15 whose serogroup 6 was the most frequently isolated (37%). The results of this study show that Morocco has a high frequency in Legionella pneumophila serogroup 1, which is primarily responsible for the majority of Legionnaires' disease, which will encourage the authorities to take necessary measures for the surveil- lance and preventive actions for monitoring of the disease legionellosis in Morocco.