Legionellosis.

Community-acquired legionnaires' disease (CALD) has dramatically increased in the Legionella urinary antigen (LUA) era. However, its incidence in each country depends on the specific techniques used for the diagnosis of LD and the mandatory reporting of cases to the local health surveillance system. Moreover, the most recent studies have demonstrated that no clinical data are discriminative enough for the diagnosis of LD. Clinical differences have been observed in sporadic and outbreak-reported cases demonstrating that the earlier the diagnosis of Legionella infection, the more nonspecific the clinical appearance. Fluoroquinolones are the most efficacious drugs against Legionella. The combination of these drugs with azithromycin seems to be promising in the treatment of patients with severe LD. Although outbreaks of LD will continue, the most important objective of the public health authorities should be to reduce their number and size.