Evaluation of Legiolert for Quantification of Legionella pneumophila from Bath Water Samples

Testing for Legionella spp. in public bath water samples is regulated in Japan. In this study, we used a total of 132 public bath water samples to compare the performance of Legiolert® and the conventional plate culture method for the enumeration of Legionella pneumophila. When Legiolert and plate culturing were performed at the same detection limit, L. pneumophila was detected in 26.5% of 132 samples by Legiolert, while 12.9% contained Legionella spp. (11.4% contained L. pneumophila) based on the plate culture method. Moreover, results of 83.3% of the total samples were consistent between the two methods, meaning that they were both positive or both negative. In this study, we demonstrated that Legiolert is a simpler and more effective method of monitoring for L. pneumophila in bath water samples.