Parvin Molazadeh - Legionella, cooling and ventilation systems

Background: Legionella is a gram negative bacteria responsible for Legionnaires disease, which is difficult to develop a severe form of pneumonia and can be fatal. These bacteria can grow on air conditioners and cooling and causes the epidemic. Due to the bacterial resistance to chlorine and other disinfectants This study was conducted to identify and control bacterial in cooling systems air.Methods:Cross-sectional study, the samples were taken from air conditioning systems and cooling in units of Kerman‟s Medical Sciences University. A total of 310 samples were collected of water tanks, coolers, cooling systems and air conditioning systems for hospitals, clinics, student, training, offical and dormitory.Samples were transferred to the laboratory .after concentrated and washing with acidic buffer, samples were inoculated on to BCYE medium, BMPA and MWY. Samples were incubated in 2.5% of Co2 and water and plates were examined in two weeks. Results were reported as percent of average. Compared with chi-square test, ANOVA and t-test was performed. Data were analyzed using SPSS version 20.Results: Of the 310 samples, %22.26 were infected with Legionella bacteria, of which %12.9 was related to the systems that they use water cooler. Infection with Legionella bacteria in health centers and water coolers were significantly higher. the most common bacteria Was Legionella pneumophila.Conclusion:Infection with this bacterium exists in some of the cooling systems in Kerman University of Medical Sciences and the need for control strategies to be considered.