title: Active surveillance of legionnaires disease during a prospective observational study of community- and hospital-acquired pneumonia.
abstract: A prospective surveillance study of legionnaires disease and an environmental survey of Legionella species were performed simultaneously in a general hospital. During a period of 3 years, 705 patients with pneumonia were screened with a Legionella urinary antigen test, and pneumonia was confirmed by culture and serological tests. Twelve cases of legionnaires disease were identified, none of which were hospital acquired, despite the fact that 60% of hospital water samples were contaminated with Legionella pneumophila at a concentration of more than 10(3) colony-forming units/L. The probable source of infection was identified for only 2 community-acquired cases. The results show that environmental contamination alone is not able to predict the risk of legionnaires disease. If no cases are present, monitoring of hospital water systems is of little significance; clinical surveillance is much more important.
authors.affiliation: Department of Medicine and Public Health, Division of Hygiene, University of Bologna, Via S. Giacomo 12, 40126 Bologna, Italy. erica.leoni@unibo.it
authors.forename: Erica
authors.initials: E
authors.lastname: Leoni
authors.forename: Rossella
authors.initials: R
authors.lastname: Sacchetti
authors.forename: Manuela
authors.initials: M
authors.lastname: Aporti
authors.forename: Claudio
authors.initials: C
authors.lastname: Lazzari
authors.forename: Manuela
authors.initials: M
authors.lastname: Donati
authors.forename: Franca
authors.initials: F
authors.lastname: Zanetti
authors.forename: Giovanna
authors.initials: G
authors.lastname: De Luca
authors.forename: Gian Franco
authors.initials: GF
authors.lastname: Finzi
authors.forename: Pier Paolo
authors.initials: PP
authors.lastname: Legnani
mesh_terms: D000328:Adult; D000368:Aged; D017714:Community-Acquired Infections / Q000453:epidemiology; D003428:Cross Infection / Q000453:epidemiology*; D004784:Environmental Monitoring; D062665:Epidemiological Monitoring; D005260:Female; D005618:Fresh Water / Q000382:microbiology*; D006801:Humans; D007558:Italy / Q000453:epidemiology; D016952:Legionella pneumophila / Q000302:isolation & purification*; D007877:Legionnaires' Disease / Q000453:epidemiology* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D018571:Sentinel Surveillance; D014881:Water Supply