SLIDE 1 Changing Landscape of Foodborne Disease
Arthur P. Liang, M.D., M. P. H. Senior Advisor for Food Safety Division of Foodborne Waterborne & Environmental Diseases Centers for Disease Control & Prevention
SLIDE 2
CDC & States: The vital link
CDC provides the vital link between illness in people & the food safety systems of government agencies & food producers.
SLIDE 3 Disclosures
- Findings & conclusions in this presentation are
those of the author and do not necessarily represent the views of the Centers for Disease Control & Prevention
- Thank you to HPP for invitation
- Speaker reserves the right to say something
stupid, wrong or incredibly obvious
SLIDE 4 Executive Summary
- Genomics & Information Technology:
Accelerating pace of change
- Disease & Food surveillance finding a needle in a
haystack
- Food safety bar is being raised for ALL
More Class 1 Recalls(?)
SLIDE 5 Listeria Outbreaks & Incidence, 1983-2013
Incidence (per million pop) Era Outbreaks per year Median cases per
Pre-PulseNet 0.3 69 Early PulseNet 2.3 11 Listeria Initiative 2.9 5.5
SLIDE 6 Listeria Outbreaks & Incidence, 1983-2014
Incidence (per million pop) Era Outbreaks per year Median cases per
Pre-PulseNet 0.3 69 Early PulseNet 2.3 11 Listeria Initiative 2.9 5.5 WGS 8 4.5
SLIDE 7 Listeriosis Outbreaks & Incidence*, 1983-2015
Incidence (per million pop)
WGS 7.5 4
*2015 incidence rate preliminary data from FoodNet
SLIDE 8 The bacteria and viruses that cause the most illnesses, hospitalizations, and deaths in the United States are:
- Salmonella
- Norovirus (Norwalk Virus)
- Campylobacter
- E. Coli
- Listeria
- Clostridium perfringens
https://www.foodsafety.gov/poisoning/causes/bacteriaviruses/
SLIDE 9 Accelerating pace of change…
- 1854 Era of Classical Epidemiology &
Microbiology 1920’s serotyping, 1940’s phage typing
- 1998 PulseNet Era
- 2014 Genome Sequencing Era
John Snow (1813-1858)
SLIDE 10 Era of Classical Epidemiology & Microbiology
How do we know it’s food? Outbreak investigation “church picnic” or “sore thumb”
- Large number of cases in one jurisdiction
− Detected by affected group − Local investigation − Local food handling error (s) − Local solution
SLIDE 11
Outbreak Detected by patients / their doctor
On January 12 A pediatric gastroenterologist notified the Washington State Dept of Health (WA DoH) of increase in emergency dept visits for bloody diarrhea & the hospitalization of 3 children with hemolytic uremic syndrome. January 15 No single exposure source from initial interviews Emergency Room & lab alerted for case finding
SLIDE 12 January 18
- 37 cases identified. 27 ate at same fast food chain A
- Cases named 13 different store locations of restaurant chain A
Chain has 66 restaurants in the Washington State. All received the same hamburger from the same distribution warehouse. “Controls” = No diarrhea in 2 wks, friend of a case, matched by neighborhood & age
SLIDE 13 Compare exposures of ill & well persons
Relative Risk = 1 No Association Relative Risk < 1 Negative Association Relative Risk > 1 Positive Association
Case - Control Study Calculate Relative Risk or Odds Ratio Ate Chain A hamburger Did not eat hamburger
Total
Sick 27 (73%) 10 37 Well 0 (0%) 16 16
matched odds ratio (mOR) = undefined; 95% confidence limit = 3.5 to ∞
SLIDE 14 “Local” food handling error:
Cook
ing Temperatures peratures for r hamburger burger 1992 FDA – 140o F (60o C) Washington State 155o F (68o C) Cooking temperatures at implicated restaurants ±60o C, probably less 50 gm frozen hamburger patties, cooked 1 minute on each size, regardless of whether meat was still red or not
SLIDE 15
WA DoH Advisory: Outbreak likely linked to Restaurant Chain A hamburgers
“Local” Intervention Janua nuary y 18
SLIDE 16 January nuary 18, , 1993: 93: Voluntary luntary Recall call
- Restaurant Chain A Press Release: “…measures to
ensure menu items prepared in accordance with an advisory issued by the WA DoH.”
- Recall: ~250,000 hamburger patties
SLIDE 17 2 3 4
i 0157 7 outbre reak ak linked nked to fast st-food
in hamburg burgers, ers, Pacif ific ic Northwest thwest 1993 93 *
20 30 40 50 60 70 80 10 1 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 # of cases January
US & primary culture-confirmed cases = 333
first report Improved cooking temps Public alert
*cases by date of exposure who ate Chain A hamburger on a single day
SLIDE 18
Cases of E. coli by Date of Illness Onset October 5-18, 1999 N=11
SLIDE 19 Compare exposures of ill & well persons
Case - Control Study Calculate Relative Risk or Odds Ratio
Apple cider No apple cider
Total
Sick 10 (73%) 1 11 Well 0 (0%) 24 24
matched odds ratio (mOR) = undefined; unmatched P-value < 0.00001) Relative Risk > 1 Positive Association
SLIDE 20 “Local” Intervention October 12, 1999
- OSDH ordered Orchard A to
- discontinue unpasteurized apple cider production
- recalled the apple cider
SLIDE 21
Environmental Results Inspection of orchard & juice production site: no violations found − No dropped apples − Washed & brushed apples − Preservative added − Warning labels
SLIDE 22 PulseNet Era: circa 1996 - present
In 1995, the Hubble Space Telescope found distant galaxies and star clusters never seen before.
Pulsed-field gel electrophoresis (PFGE) makes “invisible” outbreaks visible
SLIDE 23 PulseNet, since 1996
- DNA “fingerprints” shared electronically
- Kept in national database at CDC
SLIDE 24 PulseNet Era: circa 1996 - present
- Small numbers of cases in many jurisdictions
- Detected by lab-based subtype surveillance
- Multistate / Country Multi-disciplinary investigation
- More challenging to investigate
- Higher stakes?
- Identifying “new” foods/ingredients
SLIDE 25
March 2
PulseNet identifies additional 7 cases in 6 states with an indistinguishable PFGE pattern
Outbreak Detection by Lab
March 1
NY State notified CDC of 4 cases Salmonella with indistinguishable PFGE patterns
SLIDE 26 Multi-state / National investigation
March 2
- Hypothesis generating questionnaire deployed
March 2
- First multi-state conference call
- Common exposures in early interviews:
- Chicken
- Seafood
- Fresh produce
- Japanese restaurant
- FDA notified & joins call
SLIDE 27 Outbreak Detection/Hypothesis Generation
March 1
Cluster Identified
March 8
Exposure information points to seafood,
specifically sushi
7/8 report seafood, 5/8 report sushi
March 2
Investigation Initiated
SLIDE 28 Restaurant-exposure Clusters
March 22 4th cluster of unrelated ill persons at sushi same restaurant in CT March 16 3rd cluster of unrelated ill persons ate sushi from same grocery store in WI March 22 5th cluster of unrelated ill persons ate sushi same restaurant in MD March 8 2 unrelated ill persons in TX ate the same Japanese restaurant March 13 Second cluster of unrelated ill persons at same Japanese restaurant in WI
= res estaur urant ant clus uster
SLIDE 29 Case-Meals Other Customers
“Spicy Tuna” 84% 37% (range:29 - 53%)
Epi i Ana naly lysis sis of
meal l rec eceipts eipts
March 29-April 9
- Compare ill patrons to well patrons from the several restaurants with
illness clusters
Well Patron Groups
- Orders from diners who ate at
- ne of the cluster restaurants
- Orders placed during the same
meal (lunch or dinner)
- Close to the date when the ill
person ate at the restaurant
SLIDE 30 FDA A Traceb eback ack
Seafood Importer/Supplier A
April il 11
Seafood Processor A.
April 13-14 FDA issued two Import Alerts for fresh & frozen tuna from Seafood Processor A. Seafood Importer/Supplier A recalls raw yellowfin tuna scrape
SLIDE 31 Three major pillars
1) Epidemiology – interviews & loyalty cards, case-control, observed vs expected
Data from interviews of ill persons, distribution of cases in person/place/time, results of analytic epidemiologic studies, the history of pathogen & past
2) Traceback – lot codes, industry consultation
- f a suspected vehicle linked with ill persons to identify a common point where
contamination may have occurred & an assessment of the production facility at that common point
3) Laboratory – clinical, “DNA fingerprint,” food, environmental, results from testing of a cases, suspected vehicle or the production facility where contamination may have occurred
Higher epidemiologic “standard of proof”
Multi-disciplinary Evidence to implicate food
SLIDE 32
Multistate Outbreak of S Bareilly & S Nchanga Infections Associated with a Raw Scraped Ground Tuna Product, 2012
SLIDE 33
PulseNet increased the number of multistate foodborne outbreaks reported to CDC: 1973-2010
PulseNet begins
SLIDE 34 10 new food vehicles identified in multistate outbreaks, 2006 - 2009
1.
Bagged spinach, 2006
2.
Carrot juice, 2006
3.
Peanut butter, 2007 & 2009
4.
Broccoli powder on a snack food, 2007
5.
Pot pies, 2007
6.
Canned chili sauce, 2007
7.
Jalapeño & Serrano peppers, 2008
8.
White pepper, 2009
9.
Raw cookie dough, 2009
10.
Black & red pepper, 2009-10
National Foodborne Outbreak Surveillance System
SLIDE 35 13 new food vehicles identified in multistate outbreaks, 2006 - 2011
1.
Bagged spinach
2.
Carrot juice
3.
Peanut butter
4.
Broccoli powder on a snack food
5.
Dog food
6.
Pot pies
7.
Canned chili sauce
8.
Hot peppers
9.
White pepper
- 10. Raw cookie dough
- 11. Whole, raw papaya
- 12. Hazelnuts
- 13. Pine nuts
National Foodborne Outbreak Surveillance System
SLIDE 36 15 new food vehicles identified in multistate outbreaks, 2006 - 2012
1.
Bagged spinach
2.
Carrot juice
3.
Peanut butter
4.
Broccoli powder on a snack food
5.
Dog Food
6.
Pot pies/frozen meals
7.
Canned chili sauce
8.
Hot peppers
9.
Pepper
- 10. Raw cookie dough
- 11. Hazelnuts
- 12. Whole fresh papayas
- 13. Pine nuts
- 14. Kosher broiled chicken livers
- 15. Scraped tuna product
National Foodborne Outbreak Surveillance System
SLIDE 37 29 new vehicles identified in multistate outbreaks 2006 - 2015
National Foodborne Outbreak Surveillance System
1.
Bagged spinach
2.
Carrot juice
3.
Peanut butter
4.
Broccoli powder on a snack food
5.
Dog food
6.
Pot pies/frozen meals
7.
Canned hot dog chili sauce
8.
Fresh hot chili peppers
9.
Black pepper
- 10. Tahini sesame paste
- 11. Raw cookie dough
- 12. Aquatic water frogs
- 13. Fresh papaya
- 14. Frozen mamay fruit pulp
- 15. Bologna
- 16. In-shell hazelnuts
- 17. Pine nuts
- 18. Par-cooked, broiled chicken livers
- 19. Scraped tuna
- 20. Cashew cheese
- 21. Bearded dragons
- 22. Sugar cane juice
- 23. Sprouted chia seeds
- 24. Almond butter
- 25. Caramel apples
- 26. Sprouted nut butters
- 27. Dried mushrooms (in truffle oil puree)
- 28. Crested geckos
- 29. Wheat flour
SLIDE 38 32 new vehicles identified in multistate outbreaks since 2006 – May 2017
1.
Bagged spinach
2.
Carrot juice
3.
Peanut butter
4.
Broccoli powder on snack food
5.
Dog food
6.
Pot pies/frozen meals
7.
Canned hot dog chili sauce
8.
Fresh hot chili peppers
9.
Black pepper
10.
Tahini sesame paste
11.
Raw cookie dough
12.
Aquatic water frogs
13.
Fresh papaya
14.
Frozen mamay fruit pulp
15.
Bologna
16.
In-shell hazelnuts
17. Pine nuts 18. Par-cooked, broiled chicken livers 19. Scraped tuna 20. Cashew cheese 21. Bearded dragons 22. Sugar cane juice 23. Sprouted chia seeds 24. Almond butter 25. Caramel apples 26. Sprouted nut butters 27. Dried mushrooms (in truffle oil puree) 28. Crested geckos 29. Pistachios 30. Wheat flour 31. Powdered meal supplements 32. Soy nut butter
SLIDE 39
Genome Sequencing Era
WGS making the microbial “landscape” look like a different Universe Milky Way light vs radio telescope
SLIDE 40 Outbreak of Listerios is Linked to Recalled Stone Fruit
- July 2014 recall receives extensive media coverage
- Many inquiries to CDC FDA & health departments from concerned clinicians & public
- Many of whom had received automated telephone calls informing them that they had
purchased recalled fruit.
- During July 19–31, the CDC Listeria website received >500,000 page views
- Stone fruit isolates obtained from company
– 4 human isolates in 2014 with PFGE match – Patient 1 ate recalled nectarines & peaches – Patient 2 ate peaches, possibly recalled
– Patient 3 did not eat recalled fruits – Patient 4 no exposure information available
SLIDE 41 “Prediction is very difficult, esp. about the future.”
According to Yogi Berra, or Niels Bohr, or Albert Einstein, or Mark Twain, or Somebody
“Cross the river by feeling the stones.“
Deng Xiaoping 邓小平
- What will FDA / FSIS do? Swab-a-thons?
- What will CDC & state health departments do?
- Recall may trigger Outbreak investigation, instead of vice versa
- Will epidemiologists be responding more to a “food” signal?
- Long-tail, “never-ending” outbreak?
- “Outbreaks” are a “continuous variable”
- Definition of an outbreak changing?
- Greater than expected?
Source: Art Liang’s speculation
SLIDE 42 Future foodborne outbreaks more likely to be
- Dispersed in space: Multi-state, multi-national
- Dispersed in time: Multi-year
- Detected by sequence-based surveillance
- Detected as contaminated product first
Associated with
- Fresh produce & minimally processed foods
- Imported foods
- Novel food vehicles
- Novel routes & pathways of contamination
More dispersed & smaller: “low & slow”
Robert Tauxe, MD, Director, CDC Division of Foodborne, Waterborne & Environmental Diseases, September 20, 2017
SLIDE 43 Projected wgMLST database validation & deployment timeline
Apr 14 Oct 14 Apr 15 Oct 15 Apr 16 Oct 16 Apr 17 Oct 17 Apr 18 Oct 18 Apr 19
Development & internal validation Deployment Development & internal validation Deployment Development & internal validation Deployment Development & internal validation Deployment Development & internal validation External validation
← External validation ← External validation
Listeria monocytogenes Campylobacteraceae & Shiga toxin- producing
Salmonella Vibrio, Shigella &
- ther diarrheagenic
- E. coli
Cronobacter & Yersinia
External validation →
← External validation
SLIDE 44 Food Microbiology “…in this place it takes all the running you can do, to keep in the same place.“
- Red Queen to Alice in Through the Looking Glass
SLIDE 45
Thank You!