About the Authors

Ross J. Davidson

Affiliations Queen Elizabeth II Health Sciences Centre, Dalhousie University, Halifax, Canada, Dalhousie University, Halifax, Canada

Ian Davis

Affiliations Lakeridge Health Center, Oshawa, Canada, University of Toronto, Toronto, Canada

Barbara M. Willey

Affiliation Toronto Medical Laboratories/Mount Sinai Hospital Department of Microbiology, Mount Sinai Hospital, Toronto, Canada

Keyro Rizg

Affiliation Dalhousie University, Halifax, Canada

Shelly Bolotin

Affiliation University of Toronto, Toronto, Canada

Vanessa Porter

Affiliation Toronto Medical Laboratories/Mount Sinai Hospital Department of Microbiology, Mount Sinai Hospital, Toronto, Canada

Jane Polsky

Affiliation St. Michael's Hospital Department of Family & Community Medicine, Toronto, Canada

Nick Daneman

Affiliation University of Toronto, Toronto, Canada

Allison McGeer

Affiliations University of Toronto, Toronto, Canada, Toronto Medical Laboratories/Mount Sinai Hospital Department of Microbiology, Mount Sinai Hospital, Toronto, Canada

Paul Yang

Affiliation Ontario Ministry of the Environment, Etobicoke, Canada

Dennis Scolnik

Affiliation University of Toronto, Toronto, Canada

Roy Rowsell

Affiliation Lakeridge Health Center, Oshawa, Canada

Olga Imas

Affiliation Toronto Medical Laboratories/Mount Sinai Hospital Department of Microbiology, Mount Sinai Hospital, Toronto, Canada

Michael S. Silverman

msilverman@rogers.com

Affiliations Lakeridge Health Center, Oshawa, Canada, University of Toronto, Toronto, Canada

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: RD ID BW JP ND AM PY MSS. Performed the experiments: RD ID KR SB VP ND OI. Analyzed the data: JP MSS. Contributed reagents/materials/analysis tools: AM PY DS RR. Wrote the paper: RD BW DS MSS. Field Sample Collection 2002, 2003: DS. Manuscript preparation: DS. Design of replica plating, efflux, qnr and PCR experiments: RJD. Supervision of Dalhousie Laboratory performing in vitro assays on E.coli isolates: RJD. Field specimen collection 2003: ID. Design and Performance of E.coli chloroquine MIC assessments: ID. Developed laboratory methods and databases, supervised Toronto laboratory work, input on manuscript: BMW. E.coli in-vitro selection studies: KR. Coordinated water sample collection, sample transport and E.coli water sample testing: SB. Performed Laboratory work on initial E. coli isolates and other gram negative rods: VP. Performed major statistical analyses and design: JP. Carried out initial laboratory assessments of 2002 and 2003, designed clinical correlation database: ND. Supervision of Toronto Laboratory: AM. Design of stool sampling approach: AM. Design and performance of HPLC (High Performance Liquid chromatography) and MIT (Microbial Inhibition Testing) experiments: PY. Field Sample Collection 2002, 2003, 2005: RR. Field team leader: RR. Performed all PFGE (Pulsed field gel electrophoresis) typing: OI. Overall study design and supervision: MSS. Analysis of clinical data: MSS.