title: An unusually long-lasting outbreak of community-acquired Legionnaires' disease, 2005-2008, Italy.
abstract: An unusually long-lasting community-acquired outbreak of Legionnaires' disease (LD) occurred in the inhabitants of a town in northern Italy from 2005 to 2008. Overall, 43 cases were diagnosed including five deaths. Hundreds of water samples were collected for Legionella isolation but only two clinical samples were obtained. Clinical strains were ST23 as were environmental isolates detected in most Legionella-positive patients' homes and those from a public fountain. Although no Legionella was found in the municipal water mains, a continuous chlorination was applied in 2008. This action resulted in a halving of cases, although incidence remained tenfold higher than the Italian average incidence until the end of 2013, when it dropped to the expected rate. Retrospective analyses of prevalent wind direction suggested that a hidden cooling tower could have been the main cause of this uncommon outbreak, highlighting the importance of implementation of cooling tower registers in supporting LD investigations.
authors.affiliation: Istituto Superiore di Sanità,Rome,Italy.
authors.forename: M
authors.initials: M
authors.lastname: Scaturro
authors.affiliation: Istituto Superiore di Sanità,Rome,Italy.
authors.forename: S
authors.initials: S
authors.lastname: Fontana
authors.affiliation: Azienda Sanitaria Locale,Desio,Italy.
authors.forename: S
authors.initials: S
authors.lastname: Crippa
authors.affiliation: Istituto Superiore di Sanità,Rome,Italy.
authors.forename: M G
authors.initials: MG
authors.lastname: Caporali
authors.affiliation: Istituto Superiore di Sanità,Rome,Italy.
authors.forename: T
authors.initials: T
authors.lastname: Seyler
authors.affiliation: Istituto Superiore di Sanità,Rome,Italy.
authors.forename: E
authors.initials: E
authors.lastname: Veschetti
authors.affiliation: Azienda Sanitaria Locale,Desio,Italy.
authors.forename: G
authors.initials: G
authors.lastname: Villa
authors.affiliation: Istituto Superiore di Sanità,Rome,Italy.
authors.forename: M C
authors.initials: MC
authors.lastname: Rota
authors.affiliation: Istituto Superiore di Sanità,Rome,Italy.
authors.forename: M L
authors.initials: ML
authors.lastname: Ricci
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017714:Community-Acquired Infections / Q000453:epidemiology / Q000382:microbiology; D004196:Disease Outbreaks; D004197:Disease Reservoirs; D005260:Female; D006801:Humans; D007558:Italy / Q000453:epidemiology; D016952:Legionella pneumophila / Q000302:isolation & purification*; D007877:Legionnaires' Disease / Q000453:epidemiology* / Q000382:microbiology; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014871:Water Microbiology; D018508:Water Purification; D014881:Water Supply; D014919:Wind
keywords: Community-acquired pneumonia; Legionella; disinfection; public health emerging infections; water (safe)