title: A hospital outbreak of Legionella from a contaminated water supply.
abstract: The authors performed a cross-sectional epidemiological survey to investigate the source of a hospital Legionella outbreak originating in contaminated water. Water temperature and air humidity were measured around possible contamination sources. A dead-end pipe was found to contain Legionella pneumophila serogroup 1. All individuals who acquired legionellosis had spent at least 30 min within 2 m of the contamination source. Among staff, 41 of 71 were exposed, and 31 of these fell ill. All 7 patients exposed to the contaminated water acquired legionellosis. None of the 94 bed-ridden patients from the same units developed the disease. An aerosol with 60% relative air humidity was formed near the suspect water faucets, but the humidity fell rapidly farther from the water source, suggesting that desiccation decreased the risk of infection. The healthy personnel and patients closest to the source acquired legionellosis, suggesting that risk was related less to compromised patients than to exposure.
authors.affiliation: Division of Internal Medicine, University Medical Center, Ljubljana, Slovenia. marjeta.tercelj@kclj.si
authors.forename: Marjeta
authors.initials: M
authors.lastname: Tercelj-Zorman
authors.forename: Marija
authors.initials: M
authors.lastname: Seljak
authors.forename: Janez
authors.initials: J
authors.lastname: Stare
authors.forename: Joze
authors.initials: J
authors.lastname: Mencinger
authors.forename: Joze
authors.initials: J
authors.lastname: Rakovec
authors.forename: Ragnar
authors.initials: R
authors.lastname: Rylander
authors.forename: Franc
authors.initials: F
authors.lastname: Strle
mesh_terms: D000328:Adult; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology; D003430:Cross-Sectional Studies; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D006813:Humidity; D007297:Inpatients; D016952:Legionella pneumophila / Q000302:isolation & purification; D007877:Legionnaires' Disease / Q000453:epidemiology* / Q000382:microbiology; D008297:Male; D008875:Middle Aged; D010564:Personnel, Hospital; D013696:Temperature; D014871:Water Microbiology; D014881:Water Supply