title: Large outbreak of verocytotoxin-producing Escherichia coli O157 infection in visitors to a petting farm in South East England, 2009.
abstract: In the summer of 2009, an outbreak of verocytotoxigenic Escherichia coli O157 (VTEC O157) was identified in visitors to a large petting farm in South East England. The peak attack rate was 6/1000 visitors, and highest in those aged <2 years (16/1000). We conducted a case-control study with associated microbiological investigations, on human, animal and environmental samples. We identified 93 cases; 65 primary, 13 secondary and 15 asymptomatic. Cases were more likely to have visited a specific barn, stayed for prolonged periods and be infrequent farm visitors. The causative organism was identified as VTEC O157 PT21/28 with the same VNTR profile as that isolated in faecal specimens from farm animals and the physical environment, mostly in the same barn. Contact with farm livestock, especially ruminants, should be urgently reviewed at the earliest suspicion of a farm-related VTEC O157 outbreak and appropriate risk management procedures implemented without delay.
authors.affiliation: Health Protection Agency, Health Protection Service, UK. chikwe.ihekweazu@hpa.org.uk
authors.forename: C
authors.initials: C
authors.lastname: Ihekweazu
authors.forename: K
authors.initials: K
authors.lastname: Carroll
authors.forename: B
authors.initials: B
authors.lastname: Adak
authors.forename: G
authors.initials: G
authors.lastname: Smith
authors.forename: G C
authors.initials: GC
authors.lastname: Pritchard
authors.forename: I A
authors.initials: IA
authors.lastname: Gillespie
authors.forename: N Q
authors.initials: NQ
authors.lastname: Verlander
authors.forename: L
authors.initials: L
authors.lastname: Harvey-Vince
authors.forename: M
authors.initials: M
authors.lastname: Reacher
authors.forename: O
authors.initials: O
authors.lastname: Edeghere
authors.forename: B
authors.initials: B
authors.lastname: Sultan
authors.forename: R
authors.initials: R
authors.lastname: Cooper
authors.forename: G
authors.initials: G
authors.lastname: Morgan
authors.forename: P T N
authors.initials: PT
authors.lastname: Kinross
authors.forename: N S
authors.initials: NS
authors.lastname: Boxall
authors.forename: A
authors.initials: A
authors.lastname: Iversen
authors.forename: G
authors.initials: G
authors.lastname: Bickler
mesh_terms: D000818:Animals; D016022:Case-Control Studies; D002675:Child, Preschool; D003625:Data Collection; D004196:Disease Outbreaks; D004739:England / Q000453:epidemiology; D004927:Escherichia coli Infections / Q000453:epidemiology* / Q000382:microbiology* / Q000635:transmission; D019453:Escherichia coli O157 / Q000378:metabolism*; D005260:Female; D006801:Humans; D007223:Infant; D016015:Logistic Models; D008297:Male; D012307:Risk Factors; D022603:Shiga Toxins / Q000378:metabolism*; D011795:Surveys and Questionnaires; D013997:Time Factors; D015047:Zoonoses
chemical_list: D022603:Shiga Toxins
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