title: Risk factors for sporadic cases of Escherichia coli O157 infection: the importance of contact with animal excreta.
abstract: To determine environmental risk factors for sporadic E. coli O157 infection in Scotland we undertook a prospective, matched case-control study between 1 October 1996 and 31 March 1999. One hundred and eighty-three cases and 545 matched controls were recruited. Contact with animal faeces (OR = 3.65; 95% CI 1.81, 7.34: P < 0.0005) and likely contact with animal faeces (OR = 4.8; 95% CI 2.42, 9.48; P < 0.0005) emerged as strong risk factors for infection. Certain exposures (mainly food-related) were inversely associated with infection i.e. were statistically protective. Most striking was the consumption of bottled water (OR = 0.28; 95% CI 0.15, 0.52; P < 0.0005). Transmission of E. coli O157 does not occur simply through contaminated food. Members of the public need to be aware of the potential for acquiring E. coli O157 through contamination of the environment with animal faeces so that they may take measures to mitigate their risk.
authors.affiliation: Scottish Centre for Infection and Environmental Health, Glasgow.
authors.forename: M E
authors.initials: ME
authors.lastname: Locking
authors.forename: S J
authors.initials: SJ
authors.lastname: O'Brien
authors.forename: W J
authors.initials: WJ
authors.lastname: Reilly
authors.forename: E M
authors.initials: EM
authors.lastname: Wright
authors.forename: D M
authors.initials: DM
authors.lastname: Campbell
authors.forename: J E
authors.initials: JE
authors.lastname: Coia
authors.forename: L M
authors.initials: LM
authors.lastname: Browning
authors.forename: C N
authors.initials: CN
authors.lastname: Ramsay
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D004781:Environmental Exposure; D004927:Escherichia coli Infections / Q000453:epidemiology* / Q000209:etiology; D019453:Escherichia coli O157 / Q000302:isolation & purification*; D005243:Feces / Q000382:microbiology; D005260:Female; D005516:Food Microbiology; D006801:Humans; D007223:Infant; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012606:Scotland / Q000453:epidemiology