title: An international outbreak of Salmonella infections caused by alfalfa sprouts grown from contaminated seeds.
abstract: An outbreak of Salmonella serotype stanley infections occurred in the United States and Finland in 1995. The outbreak was investigated through case-control studies in Arizona, Michigan, and Finland; by isolate subtyping; and by tracing and culturing of the implicated food. Alfalfa sprout consumption was the only exposure associated with S. stanley infections in Arizona (matched odds ratio [MOR] = 11.1; 95% confidence interval [CI], 1.4-513), Michigan (MOR = 5.5; CI, 1.6-23), and Finland (MOR undefined; CI, 4.9-infinity). US and Finnish patient isolates were a unique outbreak strain distinct from S. stanley isolates not linked to the outbreak. Alfalfa sprouts eaten by patients in 6 US states and Finland were traced to seed shipped by a Dutch shipper. Thus, it was concluded that alfalfa sprouts grown from contaminated seed caused an international outbreak of > or =242 S. stanley infections in > or =17 US states and Finland. This outbreak illustrates a new mechanism through which contamination of fresh produce can cause large, widely dispersed outbreaks.
authors.affiliation: Branch of Foodborne and Diarrheal Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA.
authors.forename: B E
authors.initials: BE
authors.lastname: Mahon
authors.forename: A
authors.initials: A
authors.lastname: Pönkä
authors.forename: W N
authors.initials: WN
authors.lastname: Hall
authors.forename: K
authors.initials: K
authors.lastname: Komatsu
authors.forename: S E
authors.initials: SE
authors.lastname: Dietrich
authors.forename: A
authors.initials: A
authors.lastname: Siitonen
authors.forename: G
authors.initials: G
authors.lastname: Cage
authors.forename: P S
authors.initials: PS
authors.lastname: Hayes
authors.forename: M A
authors.initials: MA
authors.lastname: Lambert-Fair
authors.forename: N H
authors.initials: NH
authors.lastname: Bean
authors.forename: P M
authors.initials: PM
authors.lastname: Griffin
authors.forename: L
authors.initials: L
authors.lastname: Slutsker
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D000455:Medicago sativa / Q000382:microbiology*; D008875:Middle Aged; D012478:Salmonella Food Poisoning / Q000453:epidemiology*; D012639:Seeds / Q000382:microbiology