Legionella--a Case for Culture (Commentary) (Disease/Disorder Overview‪)‬

An outbreak of severe pneumonia among the participants of the American Legion convention in Philadelphia in 1976 led to the discovery of Legionella spp. as a causative agent of pneumonia1. Meanwhile it is well known that Legionella bacteria inhabit all kinds of sweet water reservoirs. The current list of validated names in the genus Legionella comprises 51 species with at least 73 serogroups (2). Approximately 75 per cent of Legionella infections are caused by L. pneumophila serogroup (sg) 1, whereas 20-30 per cent are caused by other serogroups of L. pneumophila, and 5-10 per cent by different Legionella species (3). The majority of clinical infections occur as sporadic cases, either nosocomial or community acquired. Travel-associated cases were collected and reported from a European-wide surveillance system that collects data also from other region of the world (4). Thus, recently two tourists from France and the UK became ill after staying in an Indian hotel (Joseph CA, personal communication).