Foodborne Disease Surveillance in the United States

1. Foodborne Disease Surveillance in the United States Dubai February 17, 2014 Donald J. Sharp, MD, DTM&H CDC, Atlanta The findings and conclusions in this presentation are those of the author and do not necessarily represent the views of the Centers for Disease Control and Prevention

2. What is “Surveillance”? • The systematic ongoing collection, analysis, interpretation and dissemination of data for public health action • Can be “passive” or “active”

3. Purposes of Foodborne Disease Surveillance • Detection of sporadic cases of foodborne illness • FoodNet • NNDSS, PHLIS • Detection of outbreaks of foodborne illness • Local outbreaks • Complaints of foodborne illness (common) • Lab-based serotyping sometimes finds outbreaks • Multistate outbreaks • PulseNet: laboratory-based system • OutbreakNet: Network of epidemiologists

4. What is FoodNet? • Foodborne Diseases Active Surveillance Network • Established in 1996 • Collaborative project among • CDC • United States Department of Agriculture-Food Safety Inspection Service (USDA-FSIS) • Food and Drug Administration (FDA) • 10 participating state health departments

5. FoodNet Sites 2014 46 million (~15% of U.S. population)

6. FoodNet Objectives • Determine the burdenof foodborne illness in the United States • Monitor trends in the burdenof specific foodborne illness over time • Attribute the burden of foodborne illness to specific foods and settings • Develop and assess interventions to reduce the burden of foodborne illness

7. Determine the burden of foodborne illness in the United States

8. FoodNet Surveillance • Active surveillance for laboratory-confirmed infections at >650 clinical laboratories • Salmonella, Shigella, Campylobacter, Shiga-toxin producing E. coli, Listeria monocytogenes, Yersinia enterocolitica, Vibrio, Cryptosporidium and Cyclospora • Active surveillance for hemolytic uremic syndrome (HUS)

9. Pyramid of surveillance

10. Pyramid of surveillance Lab-confirmed case reported Lab identifies pathogen Sample submitted to lab Doctor requests sample Person goes to doctor Person has symptoms

11. 2011 CDC Estimates of Foodborne Illness in the United States

12. Monitor trends in the burden of specific foodborne illness over time

13. Healthy People 2020 Objectives

14. Monitoring Trends Over Time • Use negative binomial regression model to account for: • Increase in number of participating sites • Site-to-site variation in incidence • Calculate confidence intervals • Measure change in incidence compared to 1996-1998 baseline

15. FIGURE 1 . Relative rates of laboratory-confirmed infections with Campylobacter, STEC*O157, Listeria, Salmonella, and Vibrio compared with 1996-1998 rates, by year – Foodborne Diseases Active Surveillance Network (FoodNet), United States, 1996-2012† * Shiga toxin-producing Escherichia coli. † The position of each line indicates the relative change in the incidence of that pathogen compared with 1996-1998. The actual incidences of these infections cannot be determined from this graph.

16. Outbreak Detection: Illness Complaints • Data collection content • Collect basic demographic information • Clinical information • Date/time of onset • Food history, 3-day or 5-day • Restaurants • Data collection system • Paper-based • Electronic, web-based

17. Outbreak Detection: Laboratory-based Surveillance • Serotyping • PulseNet: laboratory information • OutbreakNet: epidemiologists

18. Peter Gerner-Smidt, MD, DMS Enteric Diseases Laboratory Branch Centers for Disease Control & Prevention Atlanta, GA, USA

19. 87 labs in the PulseNet USA network

20. National Molecular Subtyping Network for Foodborne Disease Surveillance • Connects cases of illness nationwide • Allows us to find outbreaks we never knew existed • Changed our understanding of the epidemiology of Foodborne Disease Developed: 1996

21. PulseNet Data Analysis: Searching for Clusters • State health depts submit patterns electronically • CDC searches for similar patterns in past 2-4 months • CDC compares patterns visually • When cluster identified, PulseNet contacts epidemiologists Cluster of indistinguishable patterns

22. Outbreaks and Incidence of Reported Cases of Listeriosis, 1978-2008, United States PulseNet Subtyping 8 7 6 Number of outbreaks/incidence per million 5 4 3 2 1 0 1992 1978 1980 1982 1984 1986 1988 1990 1994 1996 1998 2000 2002 2004 2006 2008 Multistate outbreak Single state outbreak Incidence Incidence data from active surveillance systems (FoodNet since 1996) Outbreaks of confirmed Listeria monocytogenes reported to CDC (eFORS) 22

23. All Salmonella Typhimurium 9/1/2008 to 12/15/2008, weekly

24. All Salmonella Typhimurium 9/1/ to 12/15/2008, weekly Three subtypes highlighted

26. Before and After PulseNet 1993 Western States E. coli O157 Outbreak outbreak detected 1993726 ill, 4 deaths 39 d 2002 Colorado E. coli O157 Outbreak outbreak detected 2002 44 ill, no deaths 18 d

27. PulseNet Europe PulseNet Canada PulseNet USA PulseNet Asia Pacific PulseNet Latin America & Caribbean PulseNet Middle East PulseNet Africa As of October, 2010, 82 member countries from 7 National and Regional PulseNet Networks

28. OutbreakNet: CDC’s Foodborne Disease Outbreak Response Team Supports a national network of epidemiologists and other public health officials who investigate outbreaks of foodborne, waterborne, and other enteric illnesses in the United States Collaboration between CDC and U.S. State and local health departments U.S. Department of Agriculture (USDA) U.S. Food and Drug Administration (FDA) Works in close partnership with PulseNet The national molecular subtyping network for foodborne disease surveillance Helps ensure Rapid, coordinated detection & response to multi-state enteric disease outbreaks Promotes comprehensive outbreak surveillance

29. Focal scenario Large number of cases in one jurisdiction Detected by affected group Local investigation Local food handling error Local solution The Spectrum of Foodborne Disease Outbreaks • New dispersed scenario • Small numbers of cases in many jurisdictions • Detected by lab-based subtype surveillance • Multistate/Country investigation • Industrial contamination event • Broad implications Coordination among multiple states, agencies, and countries is critical

30. Foodborne Disease Outbreak Investigations Goals of investigations Immediate control of outbreak and prevention of illnesses Provide opportunities to identify gaps in food safety systems Outbreak epidemiology changing Globalization, centralization, industrialization Number of possible outbreaks detected has grown substantially Effective investigations key to reducing burden of foodborne disease Identify food vehicles and factors which lead to outbreaks

31. Patient BecomesIll SalmonellaIdentified Case Confirmedas Part ofOutbreak Inherent Delays in Surveillance Timeline for Reporting Cases Patient EatsContaminatedFood 1 – 3 days Contact with health care system: 1 – 5 days Diagnosis: 1 – 3 days StoolSampleCollected Shipping: 0 – 7 days Serotyping & DNA fingerprinting: 2 – 10 days Public HealthLab ReceivesSample

32. Flow of PulseNet Multistate Cluster Investigations Submission of PFGE patterns by state to CDC PulseNet Cluster identification by CDC PulseNet CDC PulseNet Epi Liaison Epi Investigation Food Vehicle Identified Regulatory Activity

33. Enteric clusters by source of report to CDC Outbreak Response and Prevention Branch, 2013 (n=221) Most clusters are reported to CDC via PulseNet Source of Report

34. Human Specimen Isolates Uploaded to PulseNet USA and Identified Clusters, 1996-2013† † Data are preliminary and subject to change * data type information may not be complete for these years

35. Average weekly number* of clusters CDC Outbreak Response Team followed by month and pathogen, February 1, 2008 – December 31, 2013 * Number per week averaged over a month period

36. Identifying new vehicles in multistate outbreaks21 new vehicles identified in multistate outbreaks since 2006 bagged spinach carrot juice peanut butter broccoli powder on a snack food dog food pot pies/frozen meals canned hot dog chili sauce fresh hot chili peppers black pepper Tahini sesame paste raw cookie dough aquatic water frogs fresh papaya frozen mamay fruit pulp bologna in-shell hazelnuts • pine nuts • par-cooked, broiled chicken livers • scraped tuna • cashew cheese • sugar cane juice

37. Thank You! CDC.gov/PulseNet CDC.gov/FoodNet CDC.gov/foodborneburden CDC.gov/outbreaknet/investigations/investigating/html CDC.gov/salmonella/typhimurium/cdc_role_outbreak.html Don Sharp das8@cdc.gov