title: An Outbreak of Foodborne Illness Caused by Enteroaggregative Escherichia coli in a High School in South Korea.
abstract: In June 2013, a diarrheal outbreak occurred among high school students in Incheon, South Korea. We investigated the outbreak to identify the pathogen and mode of transmission. A case-control study using a self-administered questionnaire was conducted by local authorities and the Korean Centers for Disease Control and Prevention. Bacterial cultures of stool samples, environmental samples, and samples of preserved food items were prepared. PCR, serotyping, and pulsed-field gel electrophoresis (PFGE) were used to identify and characterize the outbreak-related pathogen. We identified 54 cases of gastroenteritis, with symptoms including diarrhea, abdominal pain, and nausea. None of the food items served in the high school cafeteria were significantly associated with illness, although the odds ratio for kippered trotters mixed with vegetables was relatively high (odds ratio: 2.92, 95% confidence interval: 0.62-13.69). Enteroaggregative Escherichia coli (EAEC) was isolated from this item and the stool samples from 22 symptomatic students and 4 asymptomatic food handlers. The PFGE patterns of EAEC isolated from these sources were indistinguishable. This outbreak was caused by EAEC, and kippered trotters mixed with vegetables, perhaps contaminated by asymptomatic food handlers, were linked to the outbreak. This case-control study highlights the importance of safe food preparation.
authors.affiliation: Division of Epidemic Intelligence Service, Korea Centers for Disease Control and Prevention.
authors.forename: Jaeseung
authors.initials: J
authors.lastname: Shin
authors.forename: Sung-Suk
authors.initials: SS
authors.lastname: Oh
authors.forename: Kyung-Hwan
authors.initials: KH
authors.lastname: Oh
authors.forename: Ji-Hyuk
authors.initials: JH
authors.lastname: Park
authors.forename: Eun Jung
authors.initials: EJ
authors.lastname: Jang
authors.forename: Gyung Tae
authors.initials: GT
authors.lastname: Chung
authors.forename: Cheon-Kwon
authors.initials: CK
authors.lastname: Yoo
authors.forename: Geun-Ryang
authors.initials: GR
authors.lastname: Bae
authors.forename: Seung-Hak
authors.initials: SH
authors.lastname: Cho
mesh_terms: D000293:Adolescent; D016022:Case-Control Studies; D003967:Diarrhea / Q000453:epidemiology* / Q000382:microbiology; D004196:Disease Outbreaks; D016521:Electrophoresis, Gel, Pulsed-Field; D004926:Escherichia coli / Q000145:classification / Q000302:isolation & purification*; D004927:Escherichia coli Infections / Q000453:epidemiology* / Q000382:microbiology; D005260:Female; D005517:Foodborne Diseases / Q000453:epidemiology* / Q000382:microbiology; D005759:Gastroenteritis / Q000453:epidemiology* / Q000382:microbiology; D005838:Genotype; D006801:Humans; D008297:Male; D058889:Molecular Typing; D056910:Republic of Korea / Q000453:epidemiology; D012574:Schools; D065288:Serogroup; D012703:Serotyping; D011795:Surveys and Questionnaires