1. Listeriosis in the United States Benjamin J. Silk, PhD, MPH Staff Epidemiologist Enteric Diseases Epidemiology Branch, CDC Public meeting on the Interagency Retail Listeria monocytogenes Risk Assessment May 22, 2013 National Center for Emerging and Zoonotic Infectious Diseases Division of Foodborne, Waterborne, and Environmental Diseases

2. Listeria monocytogenes  Found in soil and water  Grows at refrigeration temperatures  Transmitted to people by food  Infection (listeriosis) causes severe disease in vulnerable groups

3. Higher-risk Groups Higher-risk GroupIllnesses/outcomes Pregnant womenFebrile illness, fetal loss Newborn infantsBloodstream infection, meningitis Persons with immunocompromising conditions Bloodstream infection, meningitis Older adultsBloodstream infection, meningitis

4. Incidence by Risk Group, 2004–2009 Pregnancy-associated

5. Scallan E et al, Emerging Infectious Diseases, 2011 PathogenIllnessesDeathsCase-fatality rate Listeria1,60026016% Campylobacter1,300,0001200.1% Salmonella1,230,0004500.5% Shiga toxin- producing E. coli O157 96,000300.5% Listeriosis is rare, but deadly

6. U.S. Listeriosis Incidence, 1986-2011 Data from sentinel site surveillance (FoodNet since 1996)

7. Progress in late 20 th Century

8. Detection of Processed Meats as Source, 1989

9. U.S. Listeriosis Incidence, 1986-2011 Data from sentinel site surveillance (FoodNet since 1996) New regulatory policies and industry efforts begin targeting meat processing

10. Hot Dog Outbreaks, 1998–2011: A Regulatory Success YearsNo. casesNo. deaths/fetal losses 199811214 199940 2000-201100 Cartwright E et al, Emerging Infectious Diseases, 2013

11. Deli Meat Outbreaks, 1998–2011: A Regulatory Success YearsNo. casesNo. deaths/fetal losses 199800 199972 2000304 2001280 2002548 200300 200400 2005131 200600 200700 200800 200900 201082 201100 Cartwright E et al, Emerging Infectious Diseases, 2013

12. U.S. Listeriosis Incidence, 1986-2011 Data from sentinel site surveillance (FoodNet since 1996) New regulatory policies and industry efforts begin targeting meat processing

13. Advent of PulseNet, 1998 PFGE patterns National database Participating laboratories

14. Before PulseNet 1978-1997 (20 years) 5 outbreaks (2 multistate) Average 54 cases/outbreak Era of PulseNet 1998-2004 (7 years) 13 outbreaks (4 multistate) Average 22 cases/outbreak Advent of PulseNet

15. New Opportunities in 21 st Century

16. U.S. Listeriosis Incidence, 1986-2011 Data from sentinel site surveillance (FoodNet since 1996) New regulatory policies and industry efforts begin targeting meat processing Lack of progress Healthy People 2020 Goal

17.  Developed in 2004  Enhanced surveillance for all cases  Nationally-standardized food history interviews  Integration with PulseNet  Expedites identification of common food sources during outbreak investigations Listeria Initiative

18. Outbreak from Whole Cantaloupe, 2011

19. Newly Recognized Sources of Listeriosis, from Outbreaks, 1998–2011 Implicated food vehicleYearNo. casesNo. deaths/fetal losses None1998-200500 Taco/nacho salad200620 Tuna salad200853 Sprouts200820 None200900 Pre-cut celery2010105 Whole cantaloupe201114734 Cartwright E et al, Emerging Infectious Diseases, 2013

20. Mexican-style Cheese Outbreaks, 1998–2011: A Continuing Problem YearNo. casesNo. deaths/fetal losses 199800 199900 2000130 200100 200200 2003121 200400 2005120 200600 200700 200880 2009260 201061 201120 Cartwright E et al, Emerging Infectious Diseases, 2013

21. Incidence by Ethnicity, 2004–2009 Illnesses per 100,000 people

22. Outbreak from Imported Cheese that Cross-Contaminated Other Cheeses, 2012  Imported, contaminated ricotta salata was outbreak source  Cross-contamination of other cheeses propagated the outbreak  First U.S. listeriosis outbreak associated with cut and repackaged cheeses

23. Summary  Progress in late 20 th Century Interventions targeted processed hot dogs and deli meats Enhanced outbreak detection  New Opportunities in 21 st Century Identify sources of sporadic cases via continued enhancement of outbreak detection (e.g., Listeria Initiative, whole genome sequencing) Newly recognized raw produce sources Persistent sources, especially Mexican-style cheese Pasteurized and unpasteurized Targeting contamination and cross-contamination in retail settings

24. Public Health Approach to Prevention Surveillance Epidemiological Investigation Applied Research Prevention Measures

25. For more information please contact Centers for Disease Control and Prevention 1600 Clifton Road NE, Atlanta, GA 30333 Telephone: 1-800-CDC-INFO (232-4636)/TTY: 1-888-232-6348 Visit: www.cdc.gov | Contact CDC at: 1-800-CDC-INFO or www.cdc.gov/info The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention. National Center for Emerging and Zoonotic Infectious Diseases Division of Foodborne, Waterborne, and Environmental Diseases