Vincent J. Radke, MPH, RS, CP-FS, DAAS, CPH Sanitarian Centers for Disease Control and Prevention

1. Understanding Foodborne Disease Outbreaks Using Environmental Assessments: The Importance of Antecedents to Contributing Factors Vincent J. Radke, MPH, RS, CP-FS, DAAS, CPH Sanitarian Centers for Disease Control and Prevention Sixth International Conference on Food Safety Dubai, 2011 National Center for Environmental Health Environmental Health Services Branch

2. Definitions • Environmental Assessment • The component of an outbreak investigation that fully describes how the environment contributed to the introduction and or transmission of agents that cause illness. Environment is everything external to the host, including air, food, water, animals, plants, climate, etc as well as people, social and built environments. All aspects of the external environment can be listed as variables that, in relation to transmission, are neutral, conducive or protective. From this description contributing factors and environmental antecedents to an outbreak can be determined. • NOT an inspection

3. Definitions • Contributing Factors • The factors likely to be conducive to the contamination and survival of the etiologic agent or suspected agent and/or to its growth or proliferation. • Contamination Factors (C1-15) • Toxic substance part of the tissue , Contaminated raw product, Cross-contamination of ingredients , Bare-hand contact by a food handler/worker/preparer who is suspected to be infectious • Proliferation Factors (P1-12) • Improper cold holding due to malfunctioning refrigeration equipment, Improper hot holding due to improper procedure or protocol, Prolonged cold storage • Survival Factors (S1-4) • Insufficient time and/or temperature during cooking/heat processing , Insufficient time and/or temperature during reheating

4. Definitions • Environmental Antecedents • Root causes • Supporting factor(s) to the contamination, survival or increase of biological or chemical agents in food • They may be related to • People • Equipment • Process • Food • Economics • Behavior • Other circumstances

5. EXAMPLE • What caused the outbreak? Campylobacter Jejuni (CJ) in the “cooked” chicken (EPI, LAB, ENV Assessment) • Why was CJ in the “cooked" chicken? Insufficient temperature during cooking to kill CJ (Contributing Factor) • Why was there insufficient temperature during the cooking process to kill CJ? The cook did not know the temperature (Environmental Antecedent)

6. Environmental Assessments • Describes how the environment contributes to the introduction and or transmission of agents that cause illness • Objectives of the assessment • Identify contributing factors • Identify environmental antecedents • Generate recommendations for informed interventions

7. Relationship of Environmental Antecedents to Contributing Factors Outbreak Contamination at preparation step Internal System Elements People Equipment Processes Foods Economics (Icons for Navigation and Learner Controls) Contributing Factor A Bare-hand contact by a food handler/worker/preparer who is suspected to be infectious Contributing Factor X Documents Whiteboard No sick leave Afraid of reporting No policy No supervision Lack of knowledge Hands not washed No gloves used PEOPLE Handling after kill step No kill step Multiple steps involving process PROCESS Web Pages Minimum wage Equipment costs Glove costs ECONOMICS Lack of hand wash sinks Location of hand wash sinks Lack of supplies for hand wash sinks No supervision Not enough water available Not enough gloves available EQUIPMENT FOOD

8. Past Present Future Foodborne Illness Outbreak Environmental Assessment Routine Regulatory Inspections Physical Facility Plan Review HACCP Plan Development

9. Adverse Health Outcomes Increasing Severity of illness Lab (Identify and/or confirm Agent) Outbreak Using Environmental Assessments to Investigate Disease Outbreaks No illness prevention successful Contributing Factors Protective System prevention unsuccessful Medium (food, water, Wastewater, Air, etc.) Exposure Environmental Health Assessment Process Epidemiology Equipment People Economics Environmental Antecedents

10. EHS-Net • Environmental Health Specialist Network • Pronounced “S – Net” • www.cdc.gov/nceh/ehs/EHSNet/default.htm

11. StudyIntroduction • Foodborne outbreaks investigations represent one aspect of the overall foodborne disease surveillance system • Environmental assessments of investigations provide food safety programs with better understanding of contributing factors and environmental assessments • While contributing factors are sometimes captured these factors are not framed in the context within which they occurred • Environmental antecedents help provide a meaningful context for contributing factors

12. Purpose • The purpose of this study was to identity contributing factors to foodborne illness outbreaks in food service establishments (restaurants, delis, schools, etc) and to describe the characteristics, policies, and practices (possible environmental antecedents) of these establishments via environmental assessments

13. Methods • The study was conducted by the Environmental Health Specialists Network (EHS-Net). EHS-Net is a collaborative project of CDC, USFDA, USDA and nine states ( CA, CT, GA, IA, MN, NY, OR, RI, TN) • Descriptive study to collect information on contributing factors and antecedents (food handling policies and practices) • Data collection based on interview with a kitchen manager, observations in the kitchen, development of a food flow of the suspected or identified vehicle, and sometimes re-enactment of the food handling practices used for the vehicle

14. Methods (Cont.) • Descriptive analysis of the data set included univarate frequencies and cross-tabulations for selected variables • Future analysis to include test for association using chi-square and t-test, we may use regression modeling to examine any multivariate relationships and to control for confounding

15. Results • 154 environmental assessments conducted ( June, 2006 to September , 2007) • Of those outbreaks with an identified etiology (102) 33 (30%) were bacterial and 69 (63%) viral • 84% were identified as complex; 13% were cook serve; 3 % were prep serve • Spanish was the primary language of 58% of the food workers but only 41% of the mangers could speak Spanish

16. Results(Cont.) • 95% of establishments had floor cleaning policies (37% of these were written BUT fewer had policies for cleaning food contact surfaces (food slicers 72%). In these establishments 33% had a written policy for cleaning food slicers. • More managers received paid sick leave (66%) than workers (40%) • Establishments physical characteristics potentially related to safe food handling practices such as hand sinks availability revealed the majority of establishments had hand washing sinks in the restroom (96%)

17. Results(Cont.) • Also a majority of establishments had hand washing sinks available in the work areas (94%). Hands free operated hand washing sinks were rare, found in only 4% of employee restrooms and 3% of work areas

18. Conclusions • The environmental assessment in a foodborne outbreak investigation is critical to understanding contributing factors and potential antecedents to foodborne illness, yet information regarding potential antecedents is rarely captured. • While current foodborne outbreak surveillance data may identify working while ill or poor handwashing practices as factors contributing to outbreaks information on why these circumstances may have existed is not collected or reported.

19. Conclusions(Cont.) • A systematic collection, analysis, interpretation, and dissemination of environmental data from foodborne disease outbreak investigations can support the overall foodborne disease surveillance system in a country, strengthening the ability of food control authorities at all levels of government to formulate food safety action and assess the effectiveness of these actions.

20. Vince Radkevradke@cdc.govwww.cdc.gov

21. Thank you Questions National Center for Environmental Health Environmental Health Services Branch