Characterization of Waterborne Outbreak–associatedCampylobacter jejuni, Walkerton, Ontario

Abstract

The Walkerton, Canada, waterborne outbreak of 2000 resulted from entry of Escherichia coli O157:H7 and Campylobacter spp. from neighboring farms into the town water supply. Isolates of Campylobacter jejuni and Campylobacter coli obtained from outbreak investigations were characterized by phenotypic and genotypic methods, including heat-stable and heat-labile serotyping, phage typing, biotyping, fla–restriction fragment length polymorphism (RFLP) typing, and pulsed-field gel electrophoresis. Two main outbreak strains were identified on the basis of heat-stable serotyping and fla-RFLP typing. These strains produced a limited number of types when tested by other methods. Isolates with types indistinguishable from, or similar to, the outbreak types were found only on one farm near the town of Walkerton, whereas cattle from other farms carried a variety of Campylobacter strains with different type characteristics. Results of these analyses confirmed results from epidemiologic studies and the utility of using several different typing and subtyping methods for completely characterizing bacterial populations.

Molecular Detection of Campylobacter spp. in California Gull (Larus californicus) Excreta

“…In California, the incidence of campylobacteriosis per 100,000 population was highest (29.4) among other pathogens reported in the United States. While most infections are food borne, major waterborne outbreaks have also been reported (4). From a public health perspective, Campylobacter jejuni, C. coli, and C. lari are the Campylobacter species most frequently implicated in human illness (3).…”

Comparison of Molecular Typing Methods Useful for Detecting Clusters of Campylobacter jejuni and C. coli Isolates through Routine Surveillance

“…The detection of C. jejuni in a ground beef sample was unusual. This isolate was indistinguishable by multiple typing methods from one human isolate and closely related to three additional isolates, strongly suggesting that ground beef is a source of human infection with C. jejuni (8,38), especially in the absence of detection of the same type in chicken or any other source. The data presented in the current study support a growing opinion that cattle contribute significantly in some way to the burden of human disease caused by Campylobacter (26,39).…”

“…is needed. Previous investigations have identified clusters of Campylobacter isolates in clinical or environmental settings using one or more subtyping methods (8,15,22), including pulsed-field gel electrophoresis (PFGE), restriction fragment length polymorphism analysis of PCR amplicons of the flagellin gene (flaA RFLP), and DNA sequencing of the flagellin gene short variable region (flaA SVR sequencing) (16,56). Systematic typing and subtyping were found to increase the number of common-source outbreaks detected (20), and 25% of culture-positive isolates in two counties in Denmark were part of clusters, suggesting common sources of infection (V. Fussing, unpublished observations [mentioned in reference 38]).…”

Influence de la densité animale sur la concentration des coliformes fécaux dans les cours d’eau du Québec méridional, Canada

“…L'agriculture comporte un risque comme le montre l'épisode de Walkerton en mai 2000 où l'infiltration, dans un puits, d'eau contaminée par du fumier de bétail contenant Escherichia coli (E. coli) O157:H7 et Campylobacter a causé des décès (CLARk et al, 2003). Le potentiel zoonotique d'autres bactéries comme Salmonella et Yersinia et la résistance croissante des bactéries aux antibiotiques administrés aux animaux de ferme accentuent ce risque (BAPE, 2003;BICuDO et GOyAL, 2003).…”