title: Farm visits and undercooked hamburgers as major risk factors for sporadic Escherichia coli O157:H7 infection: data from a case-control study in 5 FoodNet sites.
abstract: In 1996, active surveillance in 5 Foodborne Diseases Active Surveillance Network (FoodNet) sites revealed up to a 9-fold difference in Escherichia coli O157:H7 (O157) infection incidence between sites. A matched case-control study of sporadic O157 cases was conducted in these sites from March 1996 through April 1997. Case subjects were patients with non-outbreak-related diarrheal illness who had O157 isolated from their stool samples. Control subjects were healthy persons matched by age and telephone number exchange. Overall, 196 case patients and 372 controls were enrolled. O157 infections were associated with farm exposure, cattle exposure, eating a pink hamburger (both at home and away from home), eating at a table-service restaurant, using immunosuppressive medication, and obtaining beef through a private slaughter arrangement. Variations in cattle exposures may explain a part of the regional variability of O157 infection incidence. O157 control measures should focus on reducing risks associated with eating undercooked hamburger, dining at table-service restaurants, and farm exposures.
authors.affiliation: Minnesota Department of Health, Minneapolis, MN, USA. heidi.kassenborg@state.mn.us
authors.forename: Heidi D
authors.initials: HD
authors.lastname: Kassenborg
authors.forename: Craig W
authors.initials: CW
authors.lastname: Hedberg
authors.forename: Michael
authors.initials: M
authors.lastname: Hoekstra
authors.forename: Mary C
authors.initials: MC
authors.lastname: Evans
authors.forename: Arthur E
authors.initials: AE
authors.lastname: Chin
authors.forename: Ruthanne
authors.initials: R
authors.lastname: Marcus
authors.forename: Duc J
authors.initials: DJ
authors.lastname: Vugia
authors.forename: Kirk
authors.initials: K
authors.lastname: Smith
authors.forename: Shama Desai
authors.initials: SD
authors.lastname: Ahuja
authors.forename: Laurence
authors.initials: L
authors.lastname: Slutsker
authors.forename: Patricia M
authors.initials: PM
authors.lastname: Griffin
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D016022:Case-Control Studies; D002417:Cattle; D002648:Child; D002675:Child, Preschool; D004927:Escherichia coli Infections / Q000453:epidemiology*; D019453:Escherichia coli O157 / Q000302:isolation & purification*; D005516:Food Microbiology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007255:Information Services; D008460:Meat / Q000382:microbiology*; D008875:Middle Aged; D011159:Population Surveillance; D012307:Risk Factors