Journal Article Details Legionnaires' Disease Outbreak Associated with Hospital's Water Wall Fountain
Scientists in the Wisconsin State Laboratory of Hygiene (WSLH)/Wisconsin Occupational Health Laboratory (WOHL) Bioaerosols and WSLH Bacteriology units played a role in tracking down the cause of multiple cases of Legionnaires' Disease in southeast Wisconsin in 2010.
The outbreak was traced to a decorative water wall fountain in a hospital lobby. Efforts to determine the outbreak's cause and prevent additional Legionella infections are detailed in Feb. 2012 issue of Infection Control and Hospital Epidemiology.
In early 2010, 8 people in southeast Wisconsin developed Legionnaires' disease. Since there were only 6 reported cases of Legionnaires' in that area in the 3 years prior, public health officials knew something was awry.
An epidemiological investigation led to the hypothesis that a decorative water wall fountain in a hospital lobby that all 8 people had passed by might be the source of the outbreak. The hospital shut down the fountain and environmental samples were collected and sent to the WSLH/WOHL Bioaerosols Unit for testing.
Of the 44 samples tested, 8 were positive for Legionella pneumophila, group 1 (LP1). Those Legionella isolates were then sent to the WSLH Bacteriology Unit for pulsed-filed gel electrophoresis (aka "DNA fingerprinting") analysis. Seven of the 8 isolates had indistinguishable "DNA fingerprints".
Since the 8 patients (all of whom recovered) were started on antibiotics before respiratory specimens could be sent to the WSLH for testing, investigators were unable to make the definitive match between the Legionella bacteria infecting the patients and that found in the environmental samples. However, investigators conclude that the epidemiological data combined with the environmental contamination found through the laboratory testing supports the fountain as the source of the outbreak.
Posted By: Jan Klawitter, WSLH Public Affairs
Date: Janaury 26, 2012