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Outbreak of Salmonella enterica serotype I 4,5,12:i:- infections: the challenges of hypothesis generation and microwave cooking

  • R. K. MODY (a1) (a2), S. MEYER (a3), E. TREES (a2), P. L. WHITE (a4), T. NGUYEN (a2), R. SOWADSKY (a5), O. L. HENAO (a2), P. C. LAFON (a2), J. AUSTIN (a2), I. AZZAM (a5), P. M. GRIFFIN (a2), R. V. TAUXE (a2), K. SMITH (a3) and I. T. WILLIAMS (a2)...

We investigated an outbreak of 396 Salmonella enterica serotype I 4,5,12:i:- infections to determine the source. After 7 weeks of extensive hypothesis-generation interviews, no refined hypothesis was formed. Nevertheless, a case-control study was initiated. Subsequently, an iterative hypothesis-generation approach used by a single interviewing team identified brand A not-ready-to-eat frozen pot pies as a likely vehicle. The case-control study, modified to assess this new hypothesis, along with product testing indicated that the turkey variety of pot pies was responsible. Review of product labels identified inconsistent language regarding preparation, and the cooking instructions included undefined microwave wattage categories. Surveys found that most patients did not follow the product's cooking instructions and did not know their oven's wattage. The manufacturer voluntarily recalled pot pies and improved the product's cooking instructions. This investigation highlights the value of careful hypothesis-generation and the risks posed by frozen not-ready-to-eat microwavable foods.

Corresponding author
*Author for correspondence: Dr R. K. Mody, MD, MPH, Centers for Disease Control and Prevention, Mailstop C-09, 1600 Clifton Road NE, Atlanta, GA 303 33USA. (Email:
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3. L Huang , J Sites . New automated microwave heating process for cooking and pasteurization of microwaveable foods containing raw meats. Journal of Food Science 2010; 75: E110E115.

13. B Kenny , R Hall , S Cameron . Consumer attitudes and behaviours – key risk factors in an outbreak of Salmonella typhimurium phage type 12 infection sourced to chicken nuggets. Australian and New Zealand Journal of Public Health 1999; 23: 164167.

17. EM Ribot , Standardization of pulsed-field gel electrophoresis protocols for the subtyping of Escherichia coli O157:H7, salmonella, and shigella for PulseNet. Foodborne Pathogens and Disease 2006; 3: 5967.

18. JM Rounds , Salmonella enterica pulsed-field gel electrophoresis clusters, Minnesota, USA, 2001–2007. Emerging Infectious Diseses 2010; 16: 16781685.

19. CR Jackson , Introduction to United States Department of Agriculture VetNet: status of salmonella and campylobacter databases from 2004 through 2005. Foodborne Pathogens and Disease 2007; 4: 241248.

20. CR Mehta , NR Patel . Exact logistic regression: theory and examples. Statistics in Medicine 1995; 14: 21432160.

29. RA Heddleson , S Doores , RC Anantheswaran . Parameters affecting destruction of Salmonella spp. by microwave-heating. Journal of Food Science 1994; 59: 447451.

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Epidemiology & Infection
  • ISSN: 0950-2688
  • EISSN: 1469-4409
  • URL: /core/journals/epidemiology-and-infection
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