1. California Spinach outbreak 2006
September 8, 2006, Wisconsin state health officials report cluster of O157:H7 illnesses
By Sept 14th, eight states reported 50 cases
205 cases, 103 hospitalizations, 31 cases of HUS
Food survey suggested Dole Baby Spinach
E. coli O157:H7 found in 13/44 bags of Dole spinach in households

2. Paicines Ranch #1
2000 head cattle ranch

7. What caused outbreak?
Still unclear

9. Walkerton, Ontario and the Public Utilities Commission

10. The Walkerton outbreak timeline
May 18, 2000: Children missing school and admitted to hospital with bloody diarrhea.
Included as part of investigation, PUC asked to check water supply, and manager assures it is safe
May 20: Medical Officer of Health issues a boil water advisory
May 24: 600 people (town population: 4800) are ill (with E. coli O157:H7, Campylobacter).

11. Colin Mayfield, Department of Biology, University of Waterloo
Well 5 drilled in Early tests indicated vulnerabilities.
: MOE inspections warn of possible surface water contamination
1980: 4/42 tests found coliform bacteria in water (ignored)
1996: PUC promotes Stan Koebel to general manager, and brother Frank to foreman. Both were grandfathered into certification.
May 3, 2000: Stan instructed Frank to replace chlorinator on well 7. Was never done. Well 7 ran until May 9, then from May
Colin Mayfield, Department of Biology, University of Waterloo

12. Colin Mayfield, Department of Biology, University of Waterloo
And then it rained…actually it flooded (May 8-12)
Well 5
Farm that was the source of the E. coli
Colin Mayfield, Department of Biology, University of Waterloo

13. Covering your tracks May 15th reading indicated coliform contamination
Retesting on May 18th confirmed
Stan Koebel starts hyperchlorinating water supply
May 19th: Stan insists water supply is safe at monthly PUC meeting
May 20th: Assures public health inspector of the same.
May 21st: After boil water alert issued, still does not report positive coliform counts.

14. Colin Mayfield, Department of Biology, University of Waterloo
Where were the issues?
Budget cutbacks left MOE short of inspectors.
1996: Ontario dismantled its water testing lab, allowed PUC to use private lab
Early concerns about potential surface water contamination ignored
Stan and Frank Koebel had no formal training, were “dialing back” chlorine levels, let wells run without chlorination.
Water samples for coliform testing deliberately misidentified
Routine chlorine tests by PUC were falsified as far back as 1979
Colin Mayfield, Department of Biology, University of Waterloo

15. Negligence and lack of funding caused…
2300 illnesses
167 confirmed to be E. coli O157:H7
116 confirmed cases of Campylobacter
65 hospitalizations
27 cases of HUS
7 deaths
1 year jail sentence for Stan Koebel, 9 months house arrest for Frank