TY - JOUR AU - Den Boer, Jeroen AU - Yzerman, Ed P.F. AU - Schellekens, Joop AU - Lettinga, Kamilla AU - Boshuizen, Hendriek AU - Van Steenbergen, Jim AU - Bosman, Arnold AU - Van den Hof, Susan AU - Van Vliet, Hans AU - Peeters, Marcel AU - Van Ketel, Ruud AU - Speelman, Peter AU - Kool, Jacob AU - Van Spaendonck, Marina A.E. Conyn T1 - A Large Outbreak of Legionnaires’ Disease at a Flower Show, the Netherlands, 1999 T2 - Emerging Infectious Disease journal PY - 2002 VL - 8 IS - 1 SP - 37 SN - 1080-6059 AB - In 1999, an outbreak of Legionnaires' disease affected many visitors to a flower show in the Netherlands. To identify the source of the outbreak, we performed an environmental investigation, as well as a case-control study among visitors and a serologic cohort study among exhibitors to measure exposure to possible sources. Of 77,061 visitors, 188 became ill (133 confirmed and 55 probable cases), for an attack rate of 0.23% for visitors and 0.61% for exhibitors. Two whirlpool spas in halls 3 and 4 of the exhibition and a sprinkler in hall 8 were culture positive for Legionella pneumophila. One of three genotypes found in both whirlpool spas was identical to the isolates from 28 of 29 culture-positive patients. Persons who paused at the whirlpool spa in hall 3 were at increased risk for becoming ill. This study illustrates that whirlpool spas may be an important health hazard if disinfection fails. KW - Legionnaires’ disease KW - outbreaks KW - environmental microbiology KW - pulsed-field gel electrophoresis KW - case-control studies KW - cohort studies KW - seroepidemiologic studies KW - the Netherlands DO - 10.3201/eid0801.010176 UR - https://wwwnc.cdc.gov/eid/article/8/1/01-0176_article ER - End of Reference