1 / 34

Pathogen Reduction Dialogue Panel 4 May 7, 2002 Characterization and Control of Food Borne Pathogens

Pathogen Reduction Dialogue Panel 4 May 7, 2002 Characterization and Control of Food Borne Pathogens. John B. Luchansky, Ph.D. Agricultural Research Service Eastern Regional Research Center Microbial Food Safety Research Unit. Characterization and Control of Food Borne Pathogens.

bernad
Download Presentation

Pathogen Reduction Dialogue Panel 4 May 7, 2002 Characterization and Control of Food Borne Pathogens

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Pathogen Reduction DialoguePanel 4May 7, 2002Characterization and Control of Food Borne Pathogens John B. Luchansky, Ph.D. Agricultural Research Service Eastern Regional Research Center Microbial Food Safety Research Unit

  2. Characterization and Control of Food Borne Pathogens John B. Luchansky, Ph.D. Agricultural Research Service Eastern Regional Research Center Microbial Food Safety Research Unit

  3. Input helpful for developing interventions • What is the targeted pathogen or indicator microbe? • Where does it reside and how long does it persist or predominate? • How many types are present and at what levels? • How does it respond to environmental cues? • Where did it come from and where might it end up? • What levels and types of the targeted microbe are tolerable and under what situations?

  4. Research Strategy Interventions • Physical (Heat) • Biological (LAB) • Chemical (Na Lactate) • Mechanical (Design change) Raw Material Fabricate Process Slaughter Finished Product Recovery/Characterization Modeling • Culture & Antibody (IMS) • Nucleic Acid (PCR, PFGE) • Genomics & Proteomics • Predictive Microbiology • (PMP, ComBase, CEMMI)

  5. Download at www.arserrc.gov/mfs/pathogen.htm

  6. Pathogen Modeling Program (PMP) The PMP is a group of models that estimate the behavior of bacterial pathogens in specific environments Through a user-friendly interface, information is provided about the effects of environmental factors on growth, toxin production, and inactivation (thermal and non-thermal)

  7. Pathogen Modeling Program (PMP) • ~5000 downloads per year • Used by ~30% of food industry to design HACCP systems • PMP-6.1 (release – May ’02) contains: • growth, survival, inactivation models • dynamic temperature and thermal inactivation models • reference database • enhanced help functions

  8. ComBase -a relational database ofpredictive microbiology information GOALS: • to organize the storage of raw microbial data sets • to assist in the development of microbial models • to provide an efficient user interface for data acquisition BENEFITS: • Enhances development of models and risk assessments • Reduces user resources necessary to locate and analyze pathogen-food specific data

  9. Center of Excellence in Microbial Modeling & Informatics

  10. Microbial Detection • ARS/NAFS Downer Dairy Cattle Survey • NAHMS 2000 Swine Survey • HIMP Microbial Surveillance Project

  11. States Participating in the National Animal Health Monitoring System (NAHMS) Swine 2000 Study • 17 states, 160 farms, •  60 samples/farm • 93% of U.S. hogs represented • 92% of producers with • 100 hogs represented

  12. National Animal Health Monitoring System (NAHMS) Swine 2000 Study • Microbial Food Safety Research Unit: • Examined feces for: E. coli O157:H7, STEC, Y. enterocolitica, and L. monocytogenes. • Determined the clonality of isolates using phenotypic and genotypic methods.

  13. Recovery of E. coli O157 from Swine Feces (NAHMS 2000 Swine Surveillance Study) Samples tested 2,526 Serotype O157-positive samples 102 (4%) Serotype O157:H7-positive samples None Ingrid Feder, Jeffrey Gray, Rachel Pearce, Eric Bush, Dave Dargatz, Pina Fratamico, F. Morgan Wallace, Anna Porto, Paula Fedorka-Cray, Robert L. Dudley, Richard Perrine, Jeffrey E. Call, and John B. Luchansky. Annual Meeting of the International Association for Food Protection (2002)

  14. Recovery of E. coli O157 from Intact Colons of Swine at a Slaughter Facility (HIMP Microbial Surveillance Project) Samples tested 305 Serotype O157-positive samples 12 (4%) Serotype O157:H7-positive samples 6 (2%) Ingrid Feder,, F. Morgan Wallace, Jeffrey E. Call, Pina Fratamico, Rachel Pearce, Paula Fedorka-Cray, Richard Perrine, and John B. Luchansky. Annual Meeting of the American Society for Microbiology (2002)

  15. Conclusions– E. coli O157:H7 and Swine • Within the timeframe and geographic scope: • Prevalence of serotype O157 isolates was similar in colon samples obtained at slaughter and fecal samples obtained on farms • Serotype O157:H7 isolates were recovered from intact colons, but not from feces

  16. Talking Points – E. coli O157:H7 and Swine • What is the impact of collection, storage, shipment, and/or methodology on recovery? • Relative to finding E. coli O157:H7 in colon samples at slaughter but not in fecal samples from farms, what is the impact of transport and holding on shedding and/or viability? • Should studies be initiated to determine the prevalence of the pathogen in matched animal/fecal samples on the farm and at slaughter?

  17. Caitriona Byrne, Irfan Erol, Jeffrey E. Call, Dennis Buege, Charles W. Kaspar, Clayton Hiemke, Paula Fedorka-Cray, Jovita Hermosillo, Takiya Ball, Andrew K. Benson, Morgan Wallace, Marcus Handy, and John B. Luchansky. USDA/ARS and National Alliance of Food Safety Funding. Annual Meeting of the International Association of Food Protection (2002). Characterization of E. coli O157:H7 from Downer and Healthy Dairy Cattle in the Upper Midwest

  18. Design – E. coli O157:H7 and dairy cattle • Two cattle types • Healthy and downer • ~200 samples from each cattle type • Two slaughter facilities • 4 (healthy) and 7 (downer) plant visits between April and October of 2001 • 404 total fecal samples from intact colons

  19. Prevalence – E. coli O157:H7 and dairy cattle • Of 404 total fecal samples: • 6% (12/203) downer cattle • 47 isolates retained • 2% (4/201) healthy cattle • 20 isolates retained

  20. Conclusions– E. coli O157:H7 and dairy cattle • Within the timeframe and geographic scope: • 3-fold higher prevalence of serotype O157:H7 isolates in downer cattle than healthy cattle. • 1.7-fold higher prevalence of antibiotic-resistant isolates in healthy cattle. • High degree of heterogeneity among all isolates as demonstrated by PFGE.

  21. Talking Points – E. coli O157:H7 and dairy cattle • Exclude downer/suspect animals and those receiving antimicrobials from meat supply??? • Channel downer/suspect and/or animals receiving antimicrobials into cooking operations??? • Conduct additional sampling to address the impact of methodology, geography, and/or seasonality etc. on prevalence. • Develop interventions to further reduce levels of undesirable microbes associated with the carcass, primal cuts and trim, and/or finished products. • Practice more prudent use of antimicrobials???

  22. Hot Dogs are . . . • “… the quintessential American food …” • “… the ultimate handheld food …” • “… always rated in the top ten of America’s favorite foods …” James Ratchford (Natl. Hot Dog & Sausage Council) Prepared Foods, August 1999

  23. Some Facts About Hot Dogs • 850 million pounds sold at retail in 1997 • 100 million pounds were poultry hot dogs • 160 million pounds were fat-free and light hot dogs • 20 billion hot dogs consumed annually • 7 billion hot dogs consumed between Memorial and Labor Days National Hot Dog and Sausage CouncilPrepared Foods, August 1999

  24. Research on L. monocytogenes in commercially-prepared frankfurters • Evaluation of recovery methods • Determination of levels & types • Optimization of formulation

  25. ARS & FSIS L. monocytogenes Frankfurter Shelf Life Study

  26. ARS & FSIS L. monocytogenes Frankfurter Shelf Life Study • Determine the prevalence, levels, and types • Sample 3000 packages/pounds of frankfurters from each of 12 commercial manufacturers • Sample packages within 5 days of manufacture and at regular intervals over a 60-day storage period at 4 and 10°C • Complete prevalence component by July of 2002

  27. USDA- ARS Package Rinse Method Recovery of Listeria monocytogenes from vacuum-sealed packages of frankfurters: comparison of the U.S. Department of Agriculture (USDA) Food Safety and Inspection Service Product Composite Enrichment Method, the USDA Agricultural Service Product Composite Rinse Method, and the USDA-ARS Package Rinse Method J. B. Luchansky, A. C. S. Porto, F. M. Wallace, and J. E. Call Journal of Food Protection 65:567-570, 2002.

  28. Recovery of L. monocytogenes from frankfurters • Conclusions: • USDA/ARS package rinse method is about 6-fold more sensitive than the approved USDA/FSIS product composite enrichment method because the package, the purge, and the product are tested • USDA/ARS package rinse method requires less hands-on manipulation of the product, which minimizes the likelihood of product contamination and decreases the time required to sample the product

  29. Fate of L. monocytogenes on Frankfurters Containing Potassium Lactate (Klac) at 4°C

  30. Fate of L. monocytogenes on Frankfurters Containing Potassium Lactate • Bacteriostatic during product storage at 4° and 10°C • Results validate the Pathogen Modeling Program • Future studies will optimize levels to achieve a desirable flavor and an appreciable antilisterial effect

  31. Listeria monocytogenes genomics:from sequence to function • Collaborators/Team Members: • USDA/ARS • NPS - Leland Ellis, Steve Kappes, James Lindsay, & Caird Rexroad • ERRC - Gaylen Uhlich, John Luchansky, Darrell Bayles, Laura Wonderling, Connie Briggs, John Cherry, & Wilda Martinez • NADC - Irene Wesley, Alissa Jourdan, & Keith Murray • NCAUR - Peter Johnsen, Cletus Kurtzman, & Todd Ward • WRRC - Robert Mandrell • TIGR - Claire Fraser, Karen Nelson, & William Nierman

  32. Listeria monocytogenes Genome Sequencing Project - Status • Closure date of 4/16/02 • Total assembly length = 2,874,238 bp • Edit and confirm single coverage areas • Annotation in progress • Comparative genomics initiated • Manuscript in preparation

  33. What can be done with the completed sequence of Listeria monocytogenes • Study gene regulation and phenotypes of interest to enhance the safety/quality of foods, such as: • Tolerance to high salt, low pH, increased water activity, cold and warm temperatures, and modified atmospheres. • Persistence in foods and/or food processing plants. • Survival in animal and human hosts. • Resistance to biological and chemical antimicrobials and sanitizers

  34. “The goal of every bacterium is to become bacteria.” Stanley Falkow

More Related