title: Molecular typing methods to investigate transmission of Escherichia coli O157:H7 from cattle to humans.
abstract: The utility of phage typing, pulsed-field gel electrophoresis (PFGE), and plasmid profile analysis was compared, to differentiate between Canadian Escherichia coli O157:H7 strains of human (n = 27) and cattle (n = 24) origin. The diversity indices for phage typing, plasmid analysis and PFGE were 0.85, 0.69 and 0.93, respectively. PFGE and phage typing were also applied to study the role of direct transmission of E. coli O157:H7 from cattle to humans on isolates collected from two separate farm outbreaks. PFGE showed that more than one E. coli O157:H7 strain with varying PFGE DNA subtype profiles, may be responsible for an outbreak, and that more than one E. coli O157:H7 subtype may be circulating on a particular farm at any one time. To our knowledge, this is one of the first reports where PFGE typing was used to verify the direct transmission of E. coli O157:H7 from cattle to humans.
authors.affiliation: Department of Microbiology, SD Laboratory Services, Sunnybrook Health Science Centre, Toronto, Ontario, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Louie
authors.forename: S
authors.initials: S
authors.lastname: Read
authors.forename: L
authors.initials: L
authors.lastname: Louie
authors.forename: K
authors.initials: K
authors.lastname: Ziebell
authors.forename: K
authors.initials: K
authors.lastname: Rahn
authors.forename: A
authors.initials: A
authors.lastname: Borczyk
authors.forename: H
authors.initials: H
authors.lastname: Lior
mesh_terms: D000818:Animals; D001434:Bacteriophage Typing; D002417:Cattle; D002418:Cattle Diseases / Q000382:microbiology / Q000635:transmission*; D017931:DNA Primers; D004269:DNA, Bacterial / Q000032:analysis; D004196:Disease Outbreaks; D016521:Electrophoresis, Gel, Pulsed-Field; D004927:Escherichia coli Infections / Q000453:epidemiology* / Q000635:transmission*; D019453:Escherichia coli O157 / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D005759:Gastroenteritis / Q000453:epidemiology* / Q000382:microbiology; D006801:Humans; D009864:Ontario / Q000453:epidemiology; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D015047:Zoonoses
chemical_list: D017931:DNA Primers; D004269:DNA, Bacterial