Legionnaires' disease outbreak in an automobile engine manufacturing plant, Ohio, 2001.
Fry A; Nemhauser J; Rutman M; Scaife H; Allan T; Salehi E; Fields B; Benson R; Nowicki S; Parrish M; Horgan T; Koch E; Besser R
Clin Infect Dis 2001 Oct; 33(7):1095
Background: Outbreaks of legionellosis have occurred in industrial settings. In March 2001, 4 cases of Legionnaires' disease (LD) were reported among workers at the same automotive plant; all were diagnosed by Legionella urine antigen testing. We sought to identify new cases and sources of Legionella transmission. Methods: A confirmed case of LD was defined as X-ray-confirmed pneumonia plus a positive urine antigen test or isolation of Legionella from respiratory secretions or lung tissue in a plant worker. We collected clinical specimens, established active surveillance for LD, and reviewed hospital and employee absentee records. An environmental investigation was conducted to look for aerosol-producing water sources. We conducted a case-control study to determine risk factors for exposure to Legionella. Cases included confirmed LD or possible cases of legionellosis, i.e., respiratory symptoms and a titer of anti-Legionella IgG antibody more than 1:1024. Controls were randomly selected workers with fewer than 2 symptoms and IgG antibody less than 1:64. Results: No additional cases occurred. L. pneumophila serogroup 1 (LP1) was isolated from 1 patient. Legionella was isolated from 18 (9%) of 197 environmental samples; 3 were LP1 but none matched the case isolate by monoclonal antibody testing. Of 484 (57% of 855) workers who agreed to participate in the case-control study, 9 met case criteria (4 confirmed, 5 possible) and 89 met criteria for controls. Visiting one specific finishing line (OR=11.83; CI=2.20-63.61), working in the finishing region of the plant (OR=3.53; CI=0.87,14.30), being a smoker (OR=4.22; CI=0.78,22.55) and having heart disease (OR=5.13; CI=1.21,21.85) were associated with disease. Conclusions: A particular finishing line in the automotive plant was the likely source of exposure. Clinicians should consider LD when treating persons from industrial settings for pneumonia, and plants should do routine maintenance designed to reduce transmission of Legionella.
Disease-incidence; Disease-transmission; Industrial-exposures; Industrial-factory-workers; Respiratory-system-disorders; Respiratory-infections; Pulmonary-system-disorders; Pulmonary-disorders; Lung-disease; Lung-disorders; Surveillance-programs
Abstract; Conference/Symposia Proceedings
Clinical Infectious Diseases. 39th Annual Meeting of the Infectious Diseases Society of America, San Francisco, California, October 25-28, 2001