title: An outbreak of Salmonella hadar associated with food consumption at a building site canteen.
abstract: A biphasic outbreak of gastroenteritis caused by Salmonella hadar affected canteen employees and workers at a construction site in central Italy in September 1994. There were 448 symptomatic cases, from 61 of whom group C Salmonella was isolated. Six cases were canteen employees. Twenty-two other individuals were asymptomatic excreters. There were 10 secondary cases. Working as a food handler at the canteen constituted an increased risk of infection, independently of ingestion of the food (odds ratio: 62.1; 95% confidence interval (CI): 9.5-406.6). Having eaten at the canteen on the 19th and 20th September was identified as risk factor for subjects symptomatic within 72 hours (relative risk (RR): 17.0, 95% CI: 2.3-124.3), and cooled meat salad was identified as the vehicle of infection (RR: 36.6, 95% CI: 14.3-93.8). The use of portable toilets was another possible route of transmission of infection for all cases (RR: 1.3, 95% CI: 1.0-1.6). The index case was a cook who had symptoms five days before the peak of the outbreak. From 27 individuals both symptomatic and asymptomatic excreters group B, group D and not-typed Salmonellas were isolated. This study underlines the problem of improper food handling in salmonellosis outbreaks and emphasizes the role of several vehicles in the transmission of salmonellosis in a community.
authors.affiliation: Department of Epidemiology, Lazio Regional Health Authority, Rome, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Faustini
authors.forename: M
authors.initials: M
authors.lastname: Sangalli
authors.forename: M
authors.initials: M
authors.lastname: Fantasia
authors.forename: R
authors.initials: R
authors.lastname: Manganello
authors.forename: E
authors.initials: E
authors.lastname: Mattaccini
authors.forename: R
authors.initials: R
authors.lastname: Trippanera
authors.forename: D
authors.initials: D
authors.lastname: Spera
authors.forename: U
authors.initials: U
authors.lastname: La Rosa
authors.forename: M T
authors.initials: MT
authors.lastname: Topi
authors.forename: F
authors.initials: F
authors.lastname: Forastiere
authors.forename: C A
authors.initials: CA
authors.lastname: Perucci
mesh_terms: D000328:Adult; D004196:Disease Outbreaks; D005260:Female; D005516:Food Microbiology; D005759:Gastroenteritis / Q000453:epidemiology*; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012475:Salmonella; D012480:Salmonella Infections / Q000453:epidemiology*