Hypothesis generation

At this point in the investigation, romaine lettuce and ground beef/hamburgers are the leading hypotheses. However, it is still early in the investigation so other plausible hypotheses should be explored.

Question 2-3: What would you do to develop other hypotheses?

  • Review the literature for sources of past E. coli O157:H7 outbreaks (see Tools below)
  • Check Outbreak Summaries to review the sources of past E. coli O157:H7 outbreaks in Canada
  • Determine if the same PFGE pattern has been observed elsewhere in the food chain and outside Canada by asking:
  • Interview cases with a standardized questionnaire to identify other common food exposures and to determine if cases report consumption of other food items at higher than expected levels.