Isolation and identification of Legionella spp. from different aquatic sources in south-west of Iran by molecular &culture methods

Legionella pneumophila, the causative agent of Legionnaires' diseases (LD) is usually transmitted to humans via inhalation of aerosols from contaminated natural and manmade water sources. These organisms may become fatal especially in immunocompromised patients and LD is the one of the important disease from a public health perspective. This survey investigated the frequency of Legionella spp. including L. pneumophila, in some cold and warm water systems in South-West of Iran by culture and PCR methods. Thirty four water samples were collected from diverse water supply systems. After acid and heat treatments of samples, inoculated onto buffered charcoal yeast extract agar. Isolated colonies were confirmed by morphological and biochemical tests. Then the isolates were examined for icmO, sidA and lidA genes by PCR assay. This study showed that frequency of L. pneumophila was 4 by culture and 14 by PCR. PCR method to be efficient and sensitive test for rapid detection of these organisms in environmental water sources. This study emphasizes the need for effective infection control and prevention strategies to minimize the risk from exposure to potential pathogens such as Legionella spp. and to create a safe working environment.