Duopath Legionella: a New Immunochromatographic Test for Simultaneous Identification of Legionella pneumophila and Legionella Species

Several molecular biological methods are increasingly being used for the identification of legionellae in man-made aquatic environments. Currently, the genus Legionella is known to include 51 species. Some of the species have been isolated only from environmental sources up to now, but it is generally accepted that all species may cause pneumonia, especially in immunocompromised persons. These huge numbers of Legionella spp. represent a very wide serological heterogeneity that can lead to unsatisfying sensitivity and specificity of serological identification tools. The specificity of Duopath Legionella was calculated by testing 50 bacterial strains isolated from water samples and grown on GVPC agar plates. The latex agglutination assay Legionella spp. recognizes seven of the most frequent Legionella non-pneumophila species causing Legionnaires’ disease but not the wide range of legionellae found in water systems, which are also suspected to be pneumonia pathogens. In many countries, water or environmental samples have to be analyzed for the presence of Legionella spp. instead of only Legionella pneumophila. Here, Duopath Legionella revealed a significant advantage over the latex assay and makes the phenotypic diagnostic gap significantly smaller. Therefore, Duopath Legionella can be considered a user-friendly, simple and reliable test for the simultaneous identification of L. pneumophila and non-pneumophila.