title: Weather and livestock risk factors for Escherichia coli O157 human infection in Alberta, Canada.
abstract: This study investigated the extent to which proximity to cattle and weather events in Alberta predispose human populations to E. coli O157 disease. Cases of human E. coli O157 infection in Alberta between 2004 and 2011 were obtained from the province's Communicable Disease Reporting System and Discharge Abstract Database. Regression models based on spatial area incorporated human infection data with livestock and weather covariates. A variety of regression models were applied (i.e. least squares, spatial lag/error, Poisson, negative binomial) to test the most appropriate approach. Ratios for the total number of calves, bulls and beef cows to human population were highlighted as significant cattle density variables in all final best-fitting models. Weather variables were not significant in final regression models averaged over the full study period. Our results provide evidence of a significant association between measures of cattle density and human E. coli O157 disease in Alberta.
authors.affiliation: Department of Mathematics and Statistics,University of Guelph,Guelph, ON,Canada.
authors.forename: N
authors.initials: N
authors.lastname: Bifolchi
authors.affiliation: Laboratory for Foodborne Zoonoses,Public Health Agency of Canada,Saint-Hyacinthe, QC,Canada.
authors.forename: P
authors.initials: P
authors.lastname: Michel
authors.affiliation: Chief Medical Officer of Health,Alberta Health,Edmonton, AB,Canada.
authors.forename: J
authors.initials: J
authors.lastname: Talbot
authors.affiliation: Health Surveillance,Alberta Health,Edmonton, AB,Canada.
authors.forename: L
authors.initials: L
authors.lastname: Svenson
authors.affiliation: Family and Population Health Division,Alberta Health,Edmonton, AB,Canada.
authors.forename: K
authors.initials: K
authors.lastname: Simmonds
authors.affiliation: Provincial Laboratory for Public Health,Edmonton, AB,Canada.
authors.forename: S
authors.initials: S
authors.lastname: Checkley
authors.affiliation: Provincial Laboratory for Public Health,Edmonton, AB,Canada.
authors.forename: L
authors.initials: L
authors.lastname: Chui
authors.affiliation: Paul Dick and Associates,Guelph, ON,Canada.
authors.forename: P
authors.initials: P
authors.lastname: Dick
authors.affiliation: Novometrix Research Inc.,Moffat, ON,Canada.
authors.forename: J B
authors.initials: JB
authors.lastname: Wilson
mesh_terms: D000416:Alberta / Q000453:epidemiology; D000818:Animals; D002170:Canada / Q000453:epidemiology; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000382:microbiology; D016208:Databases, Factual; D004927:Escherichia coli Infections / Q000175:diagnosis / Q000453:epidemiology*; D019453:Escherichia coli O157 / Q000302:isolation & purification*; D005260:Female; D006801:Humans; D015994:Incidence; D058751:Livestock; D008297:Male; D012044:Regression Analysis; D012189:Retrospective Studies; D012307:Risk Factors; D014887:Weather