Temukan di Perpustakaan

<i>Legionella spp</i> are the causative agents of Legionnaires’ diseases, which is a pneumonia of important public health concern. Ubiquitous freshwater and soil inhabitants can reach man-made water systems and cause illness. <i>Legionella</i> enumeration and quantification in water systems is crucial for risk assessment and culture examination is the gold standard method. In this study, <i>Legionella</i> recovery from potable water samples, at presumably a low concentration of interfering microorganisms, was compared by plating on buffered charcoal yeast extract (BCYE) and glycine, vancomycin, polymyxin B, cycloheximide (GVPC) <i>Legionella</i> agar media, according to the International Standard Organization (ISO) 11731: 2017. Overall, 556 potable water samples were analyzed and 151 (27.1%) were positive for <i>Legionella</i>. <i>Legionella</i> grew on both BCYE and GVPC agar plates in 85/151 (56.3%) water samples, in 65/151 (43%) on only GVPC agar plates, and in 1/151 (0.7%) on only BCYE agar plates. In addition, GVPC medium identified <i>Legionella</i> species other than <i>pneumophila</i> in six more samples as compared with the culture on BCYE. Although the medians of colony forming units per liter (CFU/L) detected on the BCYE and GVPC agar plates were 2500 and 1350, respectively (<i>p</i>-value < 0.0001), the difference did not exceed one logarithm, and therefore is not relevant for <i>Legionella</i> risk assessment. These results make questionable the need to utilize BCYE agar plates to analyze potable water samples.