Control of Listeria monocytogenes in Ready-to-Eat Foods ...

Control of Listeria monocytogenes in Ready-to-Eat Foods: Draft Guidance

Mickey Parish, Ph.D. Senior Science Advisor

FDA CFSAN

2

Introduction

3 www.fda.gov

Lm Time Points

• “Zero tolerance” established by FDA and USDA in 1986. Published in 1996 Food Control journal

• 2003 FDA/FSIS risk assessment • 2004 FAO/WHO risk assessment • 2008 FDA draft guidance documents • 2011 JIFSAN-IRAC workshop on dose-response • Notable outbreaks (produce and dairy) • Ice cream prevalence and enumeration studies • 2015 dose-response study • 2015 FDA Food Advisory Committee meeting • 2017 FDA new draft guidance document

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Key Point from 2015 FAC Meeting

www.fda.gov

Based on knowledge gained from recent outbreaks (e.g., ice cream) and the 2015 dose-response evaluation, FDA remains uncertain that the 100/gram standard for foods that do not support growth provides an appropriate level of protection for the most vulnerable individuals in the at-risk subpopulations.

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Ice Cream Prevalence and Enumeration Results

Samples were from seven lots produced in November 2014, December 2014, January 2015, and March 2015. L. monocytogenes detected in 99% (2,307 of 2,320) of samples Geometric mean per lot of L. monocytogenes in these samples: 0.15 to 7.1 MPN/g.

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Estimated Number of Listeriosis Cases by Dose of Listeria monocytogenes from FDA 2015 Dose-Response Study

Dose of Lm Dose Log10 No. cases

1 0 0

3 0.5 0

10 1 1

32 1.5 1

100 2 1

316 2.5 3

1,000 3 6

3,160 3.5 14

10,000 4 29

31,600 4.5 60

100,000 5 115

316,000 5.5 200

1,000,000 6 308

* Pouillot et al. 2015. Table III. Risk Analysis 35(1):100

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Control of Listeria monocytogenes in Ready-to-Eat Foods: Draft Guidance

• Federal Register / Vol. 82, No. 10 / Tuesday, January 17, 2017

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Applicability

• Guidance intended for those subject to the CGMP & PC rule in 21 CFR part 117.

• Applies to production of RTE foods exposed to the environment prior to packaging where there is no Lm control measure that would significantly minimize Lm

• Replaces the previous draft guidance from 2008

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Disclaimer

• The revised draft guidance, when finalized, will represent the current thinking of FDA on this topic. It does not establish any rights for any person and is not binding on FDA or the public. You can use an alternate approach if it satisfies the requirements of the applicable statutes and regulations.

www.fda.gov

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Background • Listeria monocytogenes (Lm) in foods can cause

listericidal gastroenteritis and a severe, invasive illness (listeriosis) with a relatively high mortality rate.

• Persons at greatest risk: pregnant women and their fetuses, the elderly, and persons with weakened immune systems.

• Foods that have caused outbreaks are typically ready-to-eat (RTE) foods contaminated from the environment during manufacturing/processing.

• The greatest risk for listeriosis is from RTE foods that support growth of Lm.

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Controls

• Controls on personnel

• Design, construction and operation of the plant

• Sanitation

• Controls on raw materials and other ingredients

• Listeristatic formulation controls

• Listericidal process controls

• Storage practices, time/temperature controls

• Transportation

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Goal of an Environmental Monitoring (EM) Program

• Verify the effectiveness of control programs for Lm;

• Find Lm and harborage sites if present in a plant; and

• Ensure that corrective actions have eliminated Lm and harborage sites when found in a plant.

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Well-Designed EM Program

• Should include

– Collecting environmental samples from food contact surfaces (FCSs) and non-FCSs in a plant;

– Testing the collected environmental samples to identify potential sources of contamination; and

– Taking appropriate corrective actions if test results indicate the presence of Listeria spp. or L. monocytogenes in an environmental sample.

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More on Design of the EM Program

• The guidance recommends testing for Listeria spp. to correct situations that could potentially lead to contamination with Lm.

• The guidance recommends testing both FCSs and non-FCSs at each sampling time.

• The guidance recommends collecting environmental samples at a time several hours into production and preferably just before cleanup.

• The guidance acknowledges that finding Listeria spp. is expected.

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Risk-Based Corrective Action Procedures

• Consider:

– Whether the environmental contamination is on an FCS or a non-FCS;

– Whether testing environmental samples results in an isolated positive result or multiple positive results; and

– The proximity of a contaminated non-FCS to FCSs.

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Corrective Action Procedures

• Types of corrective actions are highly varied, depending on the situation but include: – conducting intensified cleaning and sanitizing,

– conducting intensified sampling and testing,

– conducting a root cause analysis, and

– implementing "hold and test" procedures.

• Examples are provided; it is not possible to provide a comprehensive set of corrective actions that apply in all situations.

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Escalating Actions Based on Risk • If Listeria spp. is found during routine sampling:

– Clean and sanitize the area with the positive – Retest during subsequent production cycles – Conduct comprehensive investigation if FCS – Return to routine testing if follow up (retest) samples are

negative

• If follow up testing shows a second positive: – Conduct intensified cleaning and sanitizing (with

disassembly if positive FCS) – Conduct intensified sampling and testing – Begin “hold and test” if FCS positive and product supports

growth (consider for no-growth food) – Conduct comprehensive investigation

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Corrective Actions for Listeria spp. on an FCS

• Guidance describes corrective action procedures that differ based on whether a food supports growth of Lm or not.

• Guidance recommends that for foods that do not support growth, but that are specifically intended for establishments such as hospitals and nursing homes, the corrective actions for foods that support growth be applied.

Continued

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Corrective Actions for Listeria spp. on an FCS (cont.)

• Guidance describes corrective action procedures that specify 3 consecutive days of negative tests before returning to routine sampling and testing.

• Guidance recommends that if follow up testing results in a 3rd FCS-positive for foods that support growth, production be stopped pending consultation with food safety experts

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Comprehensive Investigation for an FCS-Positive

• Examine equipment and area surrounding positive for potential harborage sites

• Review HACCP/Food Safety Plan and its implementation

• Conduct intensive sampling and testing, collecting samples several times during production and testing upstream from the positive site

Continued

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Comprehensive Investigation for FCS-Positive (cont.)

• Check maintenance records

• Interview and observe sanitation, maintenance, and production personnel

• Review production, maintenance, and sanitation procedures

• Review traffic patterns, equipment layout, and adherence to personnel hygiene procedures

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Sampling and Testing Foods

• Could be done to verify supplier control programs

• Could be done for “hold and test” during corrective actions

• Could be done to verify adequacy of Lm controls for an RTE food

• Could be done to satisfy customer request/requirement

Continued

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Sampling and Testing Foods (cont.)

• Guidance recommends that foods be tested for Lm rather than Listeria spp.

• Guidance recommends holding product represented by the food tested (e.g., food lots produced from cleanup to cleanup)

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Corrective Actions for Detection of Lm in RTE food

• Reprocess with a validated listericidal control measure,

• Divert to a use in which the food will not be consumed by humans or animals,

• Send for use in food to be consumed by animals where appropriate, or

• Destroy the lot(s) of RTE food in which L. monocytogenes has been detected

Continued

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Corrective Actions for Detection of Lm in RTE food (cont.)

• Determine whether other lot(s) of food are potentially contaminated with Lm and segregate and hold those lots of food.

• Conduct intensified sampling and testing of FCSs and non-FCSs followed by corrective actions until source of contamination is found and eliminated

• Determine whether any food in commerce would be subject to a recall.

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Analysis of Data for Trends

• Guidance recommends analyzing the data collected through environmental monitoring over time for trends that can help to continuously improve sanitation conditions in the plant by reducing the percentage of overall positive environmental samples in the plant.

• Guidance recommends analyzing product testing data for trends to improve performance and identify the need for corrective actions.

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Trends in EM Indicating Lm is Not Being Controlled

• Increases in positive environmental samples in particular sites or areas;

• Finding Listeria in the same area on multiple but non-consecutive sampling occasions (e.g., positive one week and negative the next, appearing to be isolated positives); and

• An increase in the percentage of overall positive environmental samples in the plant.

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Training

• Guidance recommends providing training in health and hygienic practices specific to control of Lm for all personnel and contractors who enter production and storage areas (e.g., individuals who conduct production, maintenance, quality assurance, quality control, or warehousing operations).

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Please Submit Comments

• Federal eRulemaking Portal: https://www.regulations.gov

• Docket No. FDA–2008–D–0096 (Formerly Docket No. 2007D–0494)

• to ensure that we consider your comment on the draft guidance before we issue the final version, submit comments by July 26, 2017

Thank You

Environmental Surveillance and Investigation : Tools for Listeria Control in the 21st Century

Prevention

Detection

Concept source: Frank Yiannas

Foodborne outbreak detection is outpacing prevention.

2006 – Mexican-style Restaurant Chain Shredded lettuce, E. coli O157:H7 2006 – Tomatoes, Salmonella Typhimurium 2006 – Fresh Spinach, E. coli O157:H7 2007 – Pizza, E. coli O157:H7 2007 – Pot Pies, Salmonella I 4,[5],12:i- 2007 – Ground Beef Patties, E. coli O157:H7 2007 – Veggie Flavored Rice and Corn Snack, Salmonella Wandsworth 2007 – Peanut Butter, Salmonella Tennessee 2008 – Raw Produce, Salmonella Saintpaul 2008 – Beef, E. coli O157:H7 2008 – Rice and Wheat Cereals, Salmonella Agona 2008 – Cantaloupes, Salmonella Litchfield 2009 – Beef, E. coli O157:H72009 - Beef, E. coli O157:H7 2009 – Prepackaged Cookie Dough, E. coli O157:H7 2009 – Alfalfa Sprouts, Salmonella Saintpaul 2009 – Peanut Butter, Salmonella Typhimurium 2009 – Pistachios, Salmonella (multiple types) 2010 – Alfalfa Sprouts, Salmonella I 4,[5],12:i- 2010 – Shell Eggs, Salmonella Enteritidis 2010 – Cheese, E. coli O157:H7 2010 – Cheesy Chicken Rice Frozen Entrée, Salmonella Chester 2010 – Frozen Mamey Fruit Pulp, Salmonella Typhi 2010 – Mexican-style Restaurant Chain, Salmonella Hartford & Baildon 2010 – Alfalfa Sprouts, Salmonella Newport 2010 – Shredded Romaine Lettuce, E. coli O157:H7 2010 – Red & Black Pepper/Italian-style Meats, Salmonella Montevideo 2010 – Beef, E. coli O157:H7 2011 – Ground Beef, Salmonella Typhimurium 2011 – Romaine Lettuce, E. coli O157:H7 2011 – Kosher Broiled Chicken Livers, Salmonella Heidelberg 2011 – Turkish Pine Nuts, Salmonella Enteritidis 2011 – Cantaloupe, Listeria monocytogenes 2011 – Ground Turkey, Salmonella Heidelberg

4

2011 – Whole, Fresh Imported Papayas, Salmonella Agona 2011 – Alfalfa and Spicy Sprouts, Salmonella Enteritidis 2011 – Travel to Germany (Fenugreek Sprouts), STEC E. coli O104 2011 – Turkey Burgers, Salmonella Hadar 2011 – Lebanon Bologna, E. coli O157:H7 2011 – Cantaloupe, Salmonella Panama 2011 – Hazelnuts, E. coli O157:H7 2012 – Spinach & Spring Mix, E. coli O157:H7 2012 – Peanut Butter, Salmonella Bredeney 2012 – Ricotta Salata Cheese, Listeria monocytogenes 2012 – Mangoes, Salmonella Bredeney 2012 – Cantaloupe, Salmonella Typhimurium and Newport 2012 – Ground Beef, Salmonella Enteritidis 2012 – Raw Scraped Ground Tuna, Salmonella Bareilly and Nchanga 2012 – Raw Clover Sprouts, E. coli O26 2012 – Mexican-style Restaurant Chain, Salmonella Enteritidis 2013 – Ready-to-Eat Salads, E. coli O157:H7 2013 – Chicken, Salmonella Heidelberg 2013 – Raw Shellfish, Vibrio parahaemolyticus 2013 – Fresh Produce, Cyclospora 2013 – Cheese, Listeriosis 2013 – Pomegranate Seeds, Hepatitis A 2013 – Tahini Sesame Paste, Salmonella Montevideo and Mbandaka 2013 – Cucumbers, Salmonella Saintpaul 2013 – Frozen Food Products, E. coli O121 2013 – Chicken, Salmonella Heidelberg 2013 – Ground Beef, Salmonella Typhimurium 2014 – Cucumbers, Salmonella Newport 2014 – Commercially Produced, Prepackaged Caramel Apples, Listeria monocytogenes 2014 – Bean Sprouts, Salmonella Enteritidis 2014 – Bean Sprouts, Listeria monocytogenes 2014 – Cheese, Listeria monocytogenes 2014 – Cilantro, Cyclospora 2014 – Nut Butter, Salmonella Braenderup 2014 – Organic Sprouted Chia Powder, Salmonella Newport, Hartford & Oranienburg

2014 – Raw Clover Sprouts, E. coli O212 2014 – Ground Beef, E. coli O157:H7 2014 – Dairy Products, Listeria monocytogenes 2014 – Chicken, Salmonella Heidelberg 2014 – Raw Cashew Cheese, Salmonella Stanley 2015 – Raw Sprouted Nut Butter Spreads, Salmonella Paratyphi B variant L(+) tartrate (+) 2015 – Rotisserie Chicken Salad, E. coli O157:H7 2015 – Mexican-style Restaurant Chain, E. coli O26 2015 – Soft Cheeses, Listeria monocytogenes 2015 – Cucumbers, Salmonella Poona 2015 – Pork, Salmonella I 4,[5],12:i- 2015 – Raw, Frozen, Stuffed Chicken Entrees, Salmonella Enteritidis 2015 – Raw, Frozen, Stuffed Chicken Entrees, Salmonella Enteritidis 2015 – Frozen Raw Tuna, Salmonella Weltevreden and Salmonella Paratyphi B variant L(+) tartrate (+) 2015 – Ice Cream, Listeria monocytogenes 2016 – Shell Eggs, Salmonella Oranienburg 2016 – Beef Products, E. coli O157:H7 2016 – Frozen Strawberries, Hepatitis A 2016 – Frozen Scallops, Hepatitis A 2016 – Alfalfa Sprouts, Salmonella Reading and Abony 2016 - Flour, E. coli O121 and O26 2016 – Frozen Vegetables, Listeria monocytogenes 2016 – Raw Milk, Listeria monocytogenes 2016 – Pistachios, Salmonella Montevideo 2016 – Alfalfa Sprouts, E. coli O157 2016 – Alfalfa Sprouts, Salmonella Muenchen and Kentucky 2016 – Organic Shake & Meal Products, Salmonella Virchow 2016 – Packaged Salads, Listeria monocytogenes 2017 – Vulto Creamery Soft Raw Milk Cheese, Listeria monocytogenes 2017 – I.M. Healty SoyNut Butter, E. coli O157:H7

N= 98

2006 – Mexican-style Restaurant Chain Shredded lettuce, E. coli O157:H7 2006 – Tomatoes, Salmonella Typhimurium 2006 – Fresh Spinach, E. coli O157:H7 2007 – Pizza, E. coli O157:H7 2007 – Pot Pies, Salmonella I 4,[5],12:i- 2007 – Ground Beef Patties, E. coli O157:H7 2007 – Veggie Flavored Rice and Corn Snack, Salmonella Wandsworth 2007 – Peanut Butter, Salmonella Tennessee 2008 – Raw Produce, Salmonella Saintpaul 2008 – Beef, E. coli O157:H7 2008 – Rice and Wheat Cereals, Salmonella Agona 2008 – Cantaloupes, Salmonella Litchfield 2009 – Beef, E. coli O157:H72009 - Beef, E. coli O157:H7 2009 – Prepackaged Cookie Dough, E. coli O157:H7 2009 – Alfalfa Sprouts, Salmonella Saintpaul 2009 – Peanut Butter, Salmonella Typhimurium 2009 – Pistachios, Salmonella (multiple types) 2010 – Alfalfa Sprouts, Salmonella I 4,[5],12:i- 2010 – Shell Eggs, Salmonella Enteritidis 2010 – Cheese, E. coli O157:H7 2010 – Cheesy Chicken Rice Frozen Entrée, Salmonella Chester 2010 – Frozen Mamey Fruit Pulp, Salmonella Typhi 2010 – Mexican-style Restaurant Chain, Salmonella Hartford & Baildon 2010 – Alfalfa Sprouts, Salmonella Newport 2010 – Shredded Romaine Lettuce, E. coli O157:H7 2010 – Red & Black Pepper/Italian-style Meats, Salmonella Montevideo 2010 – Beef, E. coli O157:H7 2011 – Ground Beef, Salmonella Typhimurium 2011 – Romaine Lettuce, E. coli O157:H7 2011 – Kosher Broiled Chicken Livers, Salmonella Heidelberg 2011 – Turkish Pine Nuts, Salmonella Enteritidis 2011 – Cantaloupe, Listeria monocytogenes 2011 – Ground Turkey, Salmonella Heidelberg

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2011 – Whole, Fresh Imported Papayas, Salmonella Agona 2011 – Alfalfa and Spicy Sprouts, Salmonella Enteritidis 2011 – Travel to Germany (Fenugreek Sprouts), STEC E. coli O104 2011 – Turkey Burgers, Salmonella Hadar 2011 – Lebanon Bologna, E. coli O157:H7 2011 – Cantaloupe, Salmonella Panama 2011 – Hazelnuts, E. coli O157:H7 2012 – Spinach & Spring Mix, E. coli O157:H7 2012 – Peanut Butter, Salmonella Bredeney 2012 – Ricotta Salata Cheese, Listeria monocytogenes 2012 – Mangoes, Salmonella Bredeney 2012 – Cantaloupe, Salmonella Typhimurium and Newport 2012 – Ground Beef, Salmonella Enteritidis 2012 – Raw Scraped Ground Tuna, Salmonella Bareilly and Nchanga 2012 – Raw Clover Sprouts, E. coli O26 2012 – Mexican-style Restaurant Chain, Salmonella Enteritidis 2013 – Ready-to-Eat Salads, E. coli O157:H7 2013 – Chicken, Salmonella Heidelberg 2013 – Raw Shellfish, Vibrio parahaemolyticus 2013 – Fresh Produce, Cyclospora 2013 – Cheese, Listeriosis 2013 – Pomegranate Seeds, Hepatitis A 2013 – Tahini Sesame Paste, Salmonella Montevideo and Mbandaka 2013 – Cucumbers, Salmonella Saintpaul 2013 – Frozen Food Products, E. coli O121 2013 – Chicken, Salmonella Heidelberg 2013 – Ground Beef, Salmonella Typhimurium 2014 – Cucumbers, Salmonella Newport 2014 – Commercially Produced, Prepackaged Caramel Apples, Listeria monocytogenes 2014 – Bean Sprouts, Salmonella Enteritidis 2014 – Bean Sprouts, Listeria monocytogenes 2014 – Cheese, Listeria monocytogenes 2014 – Cilantro, Cyclospora 2014 – Nut Butter, Salmonella Braenderup 2014 – Organic Sprouted Chia Powder, Salmonella Newport, Hartford & Oranienburg

2014 – Raw Clover Sprouts, E. coli O212 2014 – Ground Beef, E. coli O157:H7 2014 – Dairy Products, Listeria monocytogenes 2014 – Chicken, Salmonella Heidelberg 2014 – Raw Cashew Cheese, Salmonella Stanley 2015 – Raw Sprouted Nut Butter Spreads, Salmonella Paratyphi B variant L(+) tartrate (+) 2015 – Rotisserie Chicken Salad, E. coli O157:H7 2015 – Mexican-style Restaurant Chain, E. coli O26 2015 – Soft Cheeses, Listeria monocytogenes 2015 – Cucumbers, Salmonella Poona 2015 – Pork, Salmonella I 4,[5],12:i- 2015 – Raw, Frozen, Stuffed Chicken Entrees, Salmonella Enteritidis 2015 – Raw, Frozen, Stuffed Chicken Entrees, Salmonella Enteritidis 2015 – Frozen Raw Tuna, Salmonella Weltevreden and Salmonella Paratyphi B variant L(+) tartrate (+) 2015 – Ice Cream, Listeria monocytogenes 2016 – Shell Eggs, Salmonella Oranienburg 2016 – Beef Products, E. coli O157:H7 2016 – Frozen Strawberries, Hepatitis A 2016 – Frozen Scallops, Hepatitis A 2016 – Alfalfa Sprouts, Salmonella Reading and Abony 2016 - Flour, E. coli O121 and O26 2016 – Frozen Vegetables, Listeria monocytogenes 2016 – Raw Milk, Listeria monocytogenes 2016 – Pistachios, Salmonella Montevideo 2016 – Alfalfa Sprouts, E. coli O157 2016 – Alfalfa Sprouts, Salmonella Muenchen and Kentucky 2016 – Organic Shake & Meal Products, Salmonella Virchow 2016 – Packaged Salads, Listeria monocytogenes 2017 – Vulto Creamery Soft Raw Milk Cheese, Listeria monocytogenes 2017 – I.M. Healty SoyNut Butter, E. coli O157:H7

N= 98


Whole genome sequencing and next-generation sequencing technologies are expected to continue to increase the number of outbreaks which will be detected.

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2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017

Series 1


Whole genome sequencing and next-generation sequencing technologies are expected to continue to increase the number of outbreaks which will be detected.

Need more practical application from research

The industry needs to evolve

Speciation Visual Mapping PFGE WGS Microbiome analysis Metagenomics

Source: Enviromap.com; © 2016 EMAP HOLDINGS LLC

Listeria monocytogenes Suspects confirmed negative Salmonella Non-pathogenic Listeria species

Note: map has been created for demonstration only and does not reflect any actual or real data

PFGE separates large DNA Molecules to provide a DNA fingerprint

Image Source: CDC

Image Source: National Human Genome Research Institute

WGS provides a very precise DNA fingerprint by determining the order of the bases within the genome of an organism.

Microbiomes are communities of organisms present in an environment

Microbiome “profiling”

Graphics source: IBM and Mars

Natalie Dyenson, MPH North Carolina Research Campus David H Murdock Core Lab Kannapolis, NC 28081 [email protected] 704-250-3606

mailto:[email protected]

Listeria Workshop at

Food Safety Summit

Ozgur Koc [email protected]

mailto:[email protected]

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About Crunch Pak • What do we do ? Fresh Cut Apple Slicing

• To give a visual of what Crunch Pak produces each year; if you laid the slices end to end, they would wrap around the world, 2 ½ times, or 63, 604 miles.

• OR, if you take since we started, you could go to the moon and back twice…that’s a lot of apple slices…

• 100 % vertically integrated with organics

• Food Safety Program build based on a USDA CRADA Study

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•Food Safety at Crunch Pak (before recall )

• 3rd Party GFSI Audits

• All raw product is sourced from packing houses with third party GAP audits & SQF Level 2 Certified

• At least 25 audits a year by customer and third parties

• Pass all requisite audits with excellent scores

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Case Study

11/13/2013 • Phone call from WSDA; XSDA sampled 1 bag of 14oz tart, tested positive for

Listeria • Steps under our control/Actions Taken

• Traceback started for affected product

• Identify if we have any raw apples in our inventory from the same lot

• Our listeria sampling results from non-food surface contact areas show negative results for day of manufacture, October 24th day before and day after.

• Complete excessive sanitation and complete excessive Listeria sampling program

before production and during production to identify any weak spot in the system

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Chronology of Events, cont. 11/14/2013

• Crunch Pak starts extensive listeria sampling totaling 135 swabs per day ( before recall

-30 )

• FDA/WSDA teams arrive for onsite inspection and investigation

11/15/2013

• FDA conducted sampling of 34 food surface and non-food contact locations – all

negative

11/16/2013

• WSDA results negative from products sampled from retail • 10 bags with 8 different expiration dates

• CP duplicate samples of retains and WSDA samples are negative • 15 bags same production day including 2 retains from the same bagger MDA found

positive

• Packed 4 minutes before and 58 minutes later from the same bagger /found positive

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Chronology of Events, cont. 11/18/2013

• FDA conducted sampling of 80 food surface and non-food contact locations – all negative

11/19/2013

• A customer of CP under Private Label sends their team visits for audit and composite sampling of food and non-food surface locations – all negative

11/21/2013

• FDA/WSDA concluded investigation and finalized reports

• No official action indicated with their report. There will not be an FDA warning letter sent to us.

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Chronology of Events, cont.

• What does all test (WSDA & CP Finished Product, FDA, Private Label environmental swabs from food and non food surface contact areas) results mean? • Listeria is sporadic

• Listeria is in our environment

• We need to find and control it

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Conclusions to Date (11/23/2013)

Revisit Test Results

• WSDA -10 Finished Products tested

• 8 different pack dates with product coming from different lines

• Crunch Pak 15 Retains matching WSDA samples

• including 2 bags from the bagger

• 4 minutes before

• 58 minutes after

• FDA Test Results

• Food and non food surface contact areas

• 114 Samples

• Before and during production

• Private Label Consultant

• 16 samples

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Conclusions to Date, cont.

• 13 recalls in the USA related to sliced apples since 2009 • At least 1 recall per year related with Sliced Apples

• All L.Mono

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For Cause Investigation • Seek & Destroy Team

• What could have caused recall? Is the system effective to control system

• Raw Product

• Equipment Design

• Sanitation

• Facility Maintenance

• Employee Practices

• False Positive • Sampling and Testing Protocol

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Focus on Prevention and Control

• Supply Chain

• Sanitary Design

• Sanitation

• Employee and Manufacturing Practices Verification through testing:

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Recommendations for other Fresh Cut

suppliers • Raw Apple Supplier Review

• Apple Supplier Environmental Monitoring Program

• Sanitation Program & Sanitary Design

• Apple Supplier Flume System Review and Validation Studies

• Bin preventative maintenance

• Post Harvest Practices

• Use your resources to educate them

Slices Cores

Cores are divided up into 2 bags. Bags are labeled with Crunch Pak lot number

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suppliers

• It is worthwhile to consult with Listeria control “experts”

• Experience in meat/seafood industries

• Experts in sanitary design

• Someone who has fought the war on Listeria

• Do not disregard expert recommendations just because they don’t fit your business model

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suppliers

• Ensure your environmental monitoring program is robust

• Design a program based on your process and environment

• Understand “hot spots” in your facility as well as those in other RTE industries

• Previously drains

• What is around it ?

• Aggressive follow up to any positive

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suppliers

• Sanitation is a complex process and should not be taken lightly.

• The entire management team should understand the chemicals and processes that are used and why

• Regular management assessment of sanitation practices are critical

• Make management aware of sanitation metrics

• Remain knowledgeable of next generation sanitation innovations

• Do not allow Listeria to get a foot hold.

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suppliers

• Understand sanitary design of equipment and facility

• Review Niche & Harborage Areas (Top and bottom of Slicers , Inside of Shaker)

• Complete a full assessment of your equipment and facility as part of your HACCP plan

• Remove harborage points and make repairs as needed

• Employ or consult with a sanitary design expert.

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suppliers

• Understand sanitary design of equipment and facility

• •Complete a full assessment of your equipment and facility as part of your HACCP plan

• •Remove harborage points and make repairs as needed

• •Employ or consult with a sanitary design expert.

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suppliers

• Food Safety Culture Survey

• Do not underestimate the impact of each employee to control Listeria in the facility

• Regular, repeated training on the importance of Listeria control

• Understand people, equipment, and utensil traffic flow in every part of the facility.

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Items Being Implemented and Addressed

to Prevent Reoccurrence • Process Control Initiatives

• Raw Product Process Control Testing: Testing Indicators

• Environmental Monitoring Program: Daily Listeria Swabs from Non Food Surface Contact Area

• Weekly Slicing Machine Oil/Grease Micro Sampling for APC and Listeria

• Finished Product Testing

National Center for Emerging and Zoonotic Infectious Diseases

Recent Listeriosis Outbreak Investigations and the Growing Impact of Whole Genome Sequencing

Matthew Wise, MPH, PhD

Outbreak Response Team Lead

Outbreak Response and Prevention Branch

Division of Foodborne, Waterborne, and Environmental Diseases

Pre-Conference Workshop: The Latest in Listeria Control

Food Safety Summit, Chicago, IL

May 2017

Listeriosis in the United States: Epidemiology and Clinical Manifestations

1,600 invasive infections estimated to occur annually:

– Nearly all hospitalized

– Resulting in over 250 deaths

Groups at higher risk for infection or serious illness:

– Pregnant women and newborns

– Older adults

– Immunocompromised persons

Infection can cause:

– Miscarriages and stillbirths in pregnant women

– Serious illness or death in newborns

– Sepsis or meningitis in older adults

The Listeria Initiative

Because of the severity of listeriosis, state and local health departments prospectively interview all patients

– Using a standard form

– Whether or not part of an outbreak

Assists outbreak investigations in two major ways

– Early hypothesis generation

– Provides “controls” for case-case analytic methods

Detecting Outbreaks with PulseNet

Subtyping enteric bacteria is essential to identifying highly disseminated outbreaks

PulseNet laboratory network established in 1996

– Over 80 participating laboratories in the US

– 60,000+ isolates subtyped annually

Bacteria collected from ill people undergo DNA “fingerprinting” using pulse-field gel electrophoresis (PFGE)

= Bacteria with the same “fingerprint” are more likely to come from a common source

Conceptual Framework for PFGE Subtyping

Bacterial Genome

Genome “Fragments”

PFGE Patterns

Comparing isolates is analogous to comparing two books based on the number of words in each chapter Other lab workflows needed for serotype, virulence factors, etc.

“Cut” Sites

PFGE and Listeria monocytogenes

573 non-outbreak isolates in PulseNet in 2015:

– 375 PFGE pattern combinations (2 enzyme)

– 21 pattern combinations account for 25% of isolates

WGS Provides a Higher Resolution View of the Bacterial Genome

“Cut” Sites

All Positions

PFGE only gives information at a “cut” site via the banding pattern

WGS has the ability to give us information at nearly every position in the bacterial genome

Comparing isolates is analogous to comparing two books based on all the words in the book

Serotype, virulence, etc. can be identified in one workflow

Whole Genome Sequencing (WGS) Listeria Pilot Project

Started September 2013

Goal: Sequence all Listeria monocytogenes clinical, food, and environmental isolates

Near real-time (<1 week for patient isolates)

Why focus on Listeria first for WGS?

Illness is rare but serious, costly, and commonly outbreak associated

Current subtyping methods are not ideal

Listeria genome is fairly small and relatively easy to sequence and analyze

Strong epidemiologic surveillance (Listeria Initiative)

Strong regulatory component

RECENT LISTERIOSIS OUTBREAKS

Recent Multistate Listeriosis Outbreak Investigations

Year Vehicle States Cases Deaths

2017 Gourmet Soft Raw Milk Cheese 4 6 2

2016 Frozen Vegetables 4 9 3

2016 Raw Milk 2 2 1

2016 Bagged Salad Mixes 9 19 1

2015 Middle Eastern-Style Soft Cheese 10 30 3

2015 Ice Cream 4 10 3

2014 Caramel Apples 12 35 7

2014 Mung Bean Sprouts 2 5 2

2014 Hispanic-Style Cheese 4 5 1

2014 Hispanic-Style Cheese 2 8 1

2013 Gourmet Soft Cheese 5 6 1

2012 Imported Ricotta Salata Cheese 14 22 4

2011 Cantaloupes (Domestic) 28 147 33

Listeriosis and Caramel Apples

Outbreak Identification: Listeriosis and Caramel Apples

Two listeriosis illness clusters identified in November 2014

– Cluster 1: Arizona and New Mexico contact CDC regarding an increase in listeriosis cases in both states

– Cluster 2: PulseNet identifies a second cluster of 4 listeriosis cases in Minnesota and Missouri

Isolates within each cluster were closely related to one another by wgMLST, but the two clusters were not closely related genetically

Outbreak Identification: Listeriosis and Caramel Apples

Clusters combined into one investigation

– Similar timing and geographic distribution

– One patient had isolates with both PFGE patterns

Hypothesis Generation: Listeriosis and Caramel Apples

No strong epidemiologic signal from initial interview of ill people

– All cases were interviewed with the standard Listeria Initiative questionnaire

– Moved to interviews with the broader National Hypothesis Generating Questionnaire, which also did not yield a strong hypothesis

CDC then asked the states if we could perform single-interviewer open-ended interviews

– On December 15, during a interview with a patient’s spouse, a local TX official asked: “Did your spouse eat any seasonal items like caramel apples? ”

Hypothesis Testing: Listeriosis and Caramel Apples

Compared apple and caramel apple consumption among outbreak cases to ill people with unrelated listeriosis

*Ill persons with unrelated Listeria infections during the same time period

Outbreak Cases Non-outbreak Cases* p-value

Caramel Apples 28/31 (90%) 1/36 (3%) <0.001

Whole Apples 9/16 (56%) 20/30 (67%) 0.1370

Communication: Listeriosis and Caramel Apples

To prevent additional illnesses, CDC felt it was important to communicate even though a specific brand of caramel apples had not yet been identified

CDC tries to be as specific as possible about food items; rarely publicly implicates generic food products

Although “caramel apples” is a generic food product, CDC was able to specify

– Commercially produced

– Prepackaged

– Not homemade

Traceback: Listeriosis and Caramel Apples

FDA and partners collect samples:

– Apple supplier

– Caramel apple production facilities

– Whole apples in the distribution chain

Retail 1

Retail 2

Retail 3

Retail 4

Retail 5

Retail 6

Retail 7

Retail 8

Retail 9

Distributor 1

Distributor 2

Distributor 3

Manufacturer 1

Manufacturer 2

Manufacturer 3

Manufacturer 4

Manufacturer 5

Single common apple supplier

WGS Results: Listeriosis and Caramel Apples

50 isolates sequenced

– Clinical isolates from ill people

– Grower A food contact surfaces

– Grower A packing line floor drain

– Grower A apples collected in the distribution chain

Fell into 2 WGS clades, each containing closely related clinical and food/environmental isolates

Why Caramel Apples?

The acidity of apples and low water activity of caramel should not support growth of L. monocytogenes

However, L. monocytogenes inoculation studies showed a >3 log10 increase in 3 days on unrefrigerated caramel apples with sticks

– Less growth at refrigerator temperatures; no growth on caramel apples without sticks

– Hypothesis: insertion of the stick into the apple allows juice to enter the space between the caramel and the skin of the apple

Glass KA, Golden MC, Wanless BJ, Bedale W, Czuprynski C. Growth of Listeria monocytogenes within a Caramel-coated Apple Microenvironment. mBio. 6(5):e01232-15.

Listeriosis and Ice Cream

February 2015: Ice Cream Testing

Listeria monocytogenes identified in multiple samples of 2 different products collected for routine sampling by South Carolina:

7 distinct Listeria pulsed-field gel electrophoresis (PFGE) patterns

Both made on one line at a Texas Blue Bell facility

Texas collects products for testing from the facility

Identified Lm in the same two products as in South Carolina

Also found in ice cream “Scoops” produced on same line

Same PFGE patterns as found in South Carolina

March 2015: Kansas Investigation

Two patients infected with Listeria with indistinguishable PFGE patterns in late 2014 and early 2015

Both in same hospital before listeriosis onset for unrelated problems

3 other patients were in the same hospital before listeriosis onset in the previous year

Each infected with different PFGE patterns

Entire state has median of only 4 listeriosis cases/year

wgMLST (<All Characters>)

100

908070605040302010

Key

.

.

.

.

.

RunIds

.

.

CalculationStatus

.

.

cdc_id

2014L-67272015L-60492014L-60832014L-61292014L-6728

Id

PNUSAL001200PNUSAL001324PNUSAL000593PNUSAL000635PNUSAL001201

State ID

KS___211123KS___268222ks___42951KS___79910KS___211134

PFGE-AscI-pattern

GX6A16.0026GX6A16.0026GX6A16.0061GX6A16.0020GX6A16.0282

PFGE-ApaI-pattern


Outbreak

1502KSGX6-11502KSGX6-11502KSGX6-11502KSGX6-11502KSGX6-1

Serotype

.

.

.

.

.

IsolatDate

2014-10-052015-01-232014-01-142014-03-132014-10-05

12.5[0-18]

2571

Allele median[min-max] differences at node


100

908070605040302010

Key

.

.

.

.

.

RunIds

.

.

CalculationStatus

.

.

cdc_id

2014L-67272015L-60492014L-60832014L-61292014L-6728

Id

PNUSAL001200PNUSAL001324PNUSAL000593PNUSAL000635PNUSAL001201

State ID

KS___211123KS___268222ks___42951KS___79910KS___211134

PFGE-AscI-pattern


PFGE-ApaI-pattern


Outbreak

1502KSGX6-11502KSGX6-11502KSGX6-11502KSGX6-11502KSGX6-1

Serotype

.

.

.

.

.

IsolatDate

2014-10-052015-01-232014-01-142014-03-132014-10-05

Whole Genome Sequencing and Epidemic Curve Kansas, 2014–2015

0

1

2

3

Nu

mb

er

of

Illn

ess

es

Month of Illness Onset

4/4 patients with available hospital dietary records consumed milkshakes made with Blue Bell “Scoops”

4/5 isolates match PFGE patterns found in ice cream

wgMLST Analysis: Kansas Patient and Texas Ice Cream Isolates

Multiple PFGE patterns seen among ice cream isolates, but all isolates closely related by WGS (maximum 28 allele difference)

Patient isolates closely related to ice cream isolates from the Texas production facility

Four Kansas patient isolates that were closely related by

WGS


100

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2015L-61982015L-6176

2015L-6167

2015L-61942015L-6201

2015L-61652015L-6197

2015L-6177

2015L-61842015L-6202

2015L-61602015L-6162

2015L-6174

2015L-61792015L-6175

2015L-62032015L-6188

2015L-61662015L-6181

2015L-6186

2015L-62062015L-6155

2015L-62112015L-6171

2015L-6183

2015L-6189

2015L-61542015L-6208

2015L-61852015L-6182

2015L-61802015L-6153

2015L-6173

2015L-62072015L-6164

2015L-6157

2015L-6170

2015L-61722015L-6159

2015L-61582015L-6195

2015L-6163

2015L-62052015L-6209

2015L-61872015L-6156

2015L-6190

2015L-62102015L-6196

2015L-6238

2015L-62402015L-6234

2015L-6236

2015L-62372015L-6253

2015L-62122015L-6235

2015L-6255

2015L-62572015L-6254

2015L-62192015L-6221

2015L-6256

2015L-62512015L-6233

2015L-62522015L-6230

2015L-6228

2015L-62292015L-6246

2015L-62432015L-6231

2015L-6227

2014L-6083

2015L-62622015L-6263

2015L-62642015L-6245

2015L-62422014L-6727

2015L-6049

2015L-6214

2015L-6213

2015L-62322015L-6225

2015L-6223

2015L-62242015L-6260

2015L-61982015L-6176

2015L-6167

2015L-61942015L-6201

2015L-61652015L-6197

2015L-6177

2015L-61842015L-6202

2015L-61602015L-6162

2015L-6174

2015L-61792015L-6175

2015L-62032015L-6188

2015L-61662015L-6181

2015L-6186

2015L-62062015L-6155

2015L-62112015L-6171

2015L-6183

CFSAN0297972015L-6189

2015L-61542015L-6208

CFSAN029796

2015L-61852015L-6182

2015L-61802015L-6153

CFSAN029803CFSAN030113

2015L-6173

2015L-62072015L-6164

2015L-6157CFSAN030114

2015L-6170

2015L-61722015L-6159

2015L-61582015L-6195

2015L-6163

2015L-62052015L-6209

2015L-61872015L-6156

2015L-6190

2015L-62102015L-6196

2015L-6238CFSAN029822

2015L-62402015L-6234

2015L-6236

2015L-62372015L-6253

2015L-62122015L-6235

2015L-6255

2015L-62572015L-6254

2015L-62192015L-6221

2015L-6256

2015L-62512015L-6233

2015L-62522015L-6230

2015L-6228

2015L-62292015L-6246

2015L-62432015L-6231

2015L-6227CFSAN029793

PNUSAL000593

2015L-62622015L-6263

2015L-62642015L-6245

CFSAN029792

2015L-6242PNUSAL001200

PNUSAL001324CFSAN030116

2015L-6214

CFSAN0297912015L-6213

2015L-62322015L-6225

2015L-6223

2015L-62242015L-6260

SC___LM15-012

SC___LM15-011

SC___LM15-020TX___TXACF1500600

TX___TXACF1500601

SC___LM15-039

SC___LM15-008

ks___42951

SC___LM15-007

KS___211123

KS___268222TX___TXACF1500604

SC___LM15-006

GX6A16.0026

GX6A16.0061

GX6A16.0026GX6A16.0026

GX6A16.0061

GX6A16.0061

GX6A16.0061

GX6A16.0061

GX6A16.0061

GX6A16.0026

GX6A16.0026GX6A16.0026

GX6A16.0061

GX6A12.0489

GX6A12.2551

GX6A12.0077GX6A12.0489

GX6A12.2551

GX6A12.0026

GX6A12.0026

GX6A12.0026

GX6A12.0026

GX6A12.0227

GX6A12.0227GX6A12.0227

GX6A12.1512

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

not typed

not typed

not typednot typed

not typed

not typed

not typed

1/2b

not typed

1/2b

1/2bnot typed

not typed

.

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.

2015L-62222015L-6226

2015L-62392015L-6241

2015L-6161

2015L-6169

2015L-6178

2015L-62042015L-6191

2015L-6193

2015L-6168

2015L-61922015L-6258

2015L-6259

2015L-62612015L-6247

2015L-6248

2015L-6249

2015L-6250

2015L-62442015L-6220

2015L-62172015L-6218

2014L-6129

2015L-62222015L-6226

2015L-62392015L-6241

2015L-6161

2015L-6169

2015L-6178

2015L-62042015L-6191

2015L-6193

CFSAN0298152015L-6168

2015L-61922015L-6258

2015L-6259

2015L-62612015L-6247

2015L-6248

2015L-6249

2015L-6250

2015L-62442015L-6220

2015L-62172015L-6218

PNUSAL000635CFSAN029808

CFSAN030115

CFSAN030117CFSAN029809

SC___LM15-032

KS___79910SC___LM15-025

TX___TXACF1500603

TX___TXACF1500612SC___LM15-026

GX6A16.0026

GX6A16.0020GX6A16.0020

GX6A16.0020

GX6A16.0020GX6A16.0020

GX6A12.0227

GX6A12.0227GX6A12.0227

GX6A12.0227

GX6A12.0227GX6A12.0227

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-11502KSGX6-1

1502KSGX6-1

1502KSGX6-11502KSGX6-1

not typed

1/2bnot typed

not typed

not typednot typed

13 [0-28]

Testing at the Kansas Hospital

Kansas Department of Health and Environment collects Blue Bell ice cream from affected hospital

March 22: Listeria found in 3 oz. chocolate ice cream cup made in Blue Bell’s Oklahoma facility

March 23: Blue Bell recalls ice cream cups from their Oklahoma facility

Illnesses Linked to Blue Bell Oklahoma Facility?

PFGE pattern determined for Listeria from chocolate cup

Pattern only seen 6 times before, all from patients, 2010–2014

All patients previously hospitalized

Exposure to ice cream uncertain, though all hospitals received Blue Bell ice cream


100

99989796959493 Key

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Modified date

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CalculationStatus

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RunIds

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.

cdc_id

2011L-2417

2010L-1686

2013L-5169

2015L-6280

2015L-6281

2011L-2484

2014L-6678

2015L-6247

2015L-6248

2015L-6249

2015L-6250

2015L-6244

2015L-6220

2015L-6217

2015L-6218

2015L-6216

2015L-6215

2014L-6129

Id

PNUSAL001398

2010L-1686

2013L-5169

CFSAN030684

CFSAN030680

CFSAN030686

CFSAN030679

CFSAN030687

CFSAN030683

CFSAN030676

CFSAN030682

CFSAN030681

CFSAN030677

CFSAN030685

CFSAN030678

PNUSAL001405

PNUSAL001406

PNUSAL001397

FDA00008876

FDA00008873

FDA00008888

FDA00008877

CFSAN030806

PNUSAL001152

FDA00008878

FDA00008884

FDA00008872

FDA00008885

FDA00008887

FDA00008905

FDA00008889

FDA00008903

FDA00008871

FDA00008886

FDA00008904

FDA00008881

FDA00008890

FDA00008882

FDA00008883

2015L-6247

2015L-6248

2015L-6249

2015L-6250

2015L-6244

2015L-6220

2015L-6217

2015L-6218

2015L-6216

2015L-6215

PNUSAL000635

CFSAN029808

CFSAN030115

CFSAN030117

CFSAN030801

CFSAN029809

CFSAN030794

State ID

TX___TXACB1100844

AZ___PI10027002

OK___12OKE0273

KS___299129 #9

KS___299125 #5

KS___299131 #11

KS___299124 #4

KS___299132 #12

KS___299128 #8

KS___299102 #1

KS___299127 #7

KS___299126 #6

KS___299104 #2

KS___299130 #10

KS___299122 #3

OK___15OKB0255

OK___15OKB0254

TX___TXACB1101690

FCF__889278-77-A-2

FCF__FSNS15-241274-036

TX___TXACB1403595

FCF__889278-69-A-2

FCF__889278-70-A-2

FCF__889278-75-A-2

FCF__889278-78-A-2

FCF__889278-71-A-2

FCF__889278-62-A-2

FCF__889278-80-A-2

FCF__889278-67-A-2

FCF__889278-68-A-2

KS___79910

SC___LM15-025

TX___TXACF1500603

TX___TXACF1500612

FCF__FSNS15-231670-001

SC___LM15-026

FCF__FSNS15-233368-015

PFGE-AscI-pattern

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0336

GX6A16.0020

GX6A16.0020

GX6A16.0020

GX6A16.0020

GX6A16.0020

GX6A16.0020

GX6A16.0020

PFGE-ApaI-pattern

GX6A12.2255

GX6A12.2255

GX6A12.2255

GX6A12.1840

GX6A12.1840

GX6A12.1840

GX6A12.1840

GX6A12.1840

GX6A12.1840

GX6A12.1840

GX6A12.1840

GX6A12.1840

GX6A12.1840

GX6A12.1840

GX6A12.1840

GX6A12.1840

GX6A12.1840

GX6A12.2255

GX6A12.2255

GX6A12.1840

GX6A12.2255

GX6A12.1840

GX6A12.1840

GX6A12.2255

GX6A12.1840

GX6A12.1840

GX6A12.1840

GX6A12.1840

GX6A12.2255

GX6A12.2255

GX6A12.0227

GX6A12.0227

GX6A12.0227

GX6A12.0227

GX6A12.0227

GX6A12.0227

GX6A12.0227

Outbreak

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

1502KSGX6-1

Serotype

.

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.

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SourceCountry

.

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SourceState

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.

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.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

PatientAge

.

.

.

.

.

.

PatientSex

.

.

.

.

.

.

SourceType

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

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.

.

.

.

.

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.

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.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

SourceSite

Blood

Blood

Blood

Ice cream

Ice cream

Ice cream

Ice cream

Ice cream

Ice cream

Ice cream

Ice cream

Ice cream

Ice cream

Ice cream

Ice cream

Blood

Ice Cream

Ice Cream

Environmental swabs

Ice Cream

Ice Cream Product

Abscess

Ice Cream

Environmental swabs

Environmental Swabs

Environmental swabs

Environmental swabs

Environmental Swabs

Environmental swabs

Environmental Swabs

Environmental Swabs

Environmental swabs

Environmental Swabs

Environmental swabs

Environmental swabs

Environmental swabs

Environmental swabs

Dairy_Ice cream

Dairy_Ice cream

Dairy_Ice cream

Dairy_Ice cream

Dairy_Ice cream

Dairy_Ice cream

Dairy_Ice cream

Dairy_Ice cream

Ice Cream

Ice Cream

Blood

FOOD

Frozen Dessert

Frozen Dessert

Ice Cream Product

FOOD

Environmental Swab

IsolatDate

2011-03-11

2010-01-20

2012-04-01

2015-03-24

2015-03-24

2011-05-31

2015-04-01

2015-04-01

2015-03-25

2015-04-01

2015-03-23

2014-10-25

2015-04-01

2015-03-25

2015-04-01

2015-03-25

2015-03-25

2015-04-01

2015-03-25

2015-04-01

2015-04-01

2015-03-25

2015-04-01

2015-03-25

2015-03-25

2015-03-25

2015-03-25

2015-02-13

2015-02-13

2015-02-13

2015-02-13

2015-02-13

2015-02-13

2015-02-13

2015-02-13

2015

2015

2014-03-13

2015-02-17

2015-02-17

2015-03-05

2015-03-09

14[0-27]

3[0-9]

5[0-12]

April 2015: Listeriosis Cases Linked to Ice Cream from the Oklahoma Facility Using WGS

5 isolates from patients closely related to isolates from ice cream by wgMLST

2011 patient

2010 patient

2012 patient

2011 patient

2014 patient

Ice cream and environmental isolates from OK facility

wgMLST Tree with All Patient and Ice Cream Isolates

15[0-30]

16[0-47]

15[0-32]

23[0-265]

Isolates from KS patients and TX facility products all closely related (2014-2015)

Isolates from AZ, TX, and OK patients closely related to isolates from OK facility products (2010-2015)

Listeriosis and Frozen Vegetables

Outbreak Identification

In March 2016, CDC PulseNet identified a cluster of 8 Listeria monocytogenes infections

– Clinical isolates highly related to one another by WGS

– Cluster identified earlier in 2016, but no investigation opened

Also closely related by WGS to two environmental isolates

– Collected by FDA from a frozen fruit and vegetable processing facility in Oregon in March 2016

Initial Product Actions

The frozen fruit and vegetable processor conducts a voluntary market withdrawal on the basis of:

– FDA inspectional findings

– Lm isolated from the production environment, and

– The identification of closely related clinical isolates

On April 10 the first indication of product actions becomes public via a downstream recall by Schnucks

Interview Data: Finding an Food Signal

CDC develops a supplemental questionnaire

– Environmental isolates allow for more targeted questions about frozen fruits and vegetables

Four ill people interviewed were able to provide shopper card data

– Important because illnesses had occurred months to years in the past

– 3/4 ate frozen vegetables in the month prior to becoming ill

– One ill person still had leftovers in the freezer

Product Testing

Outbreak strains of Listeria identified in open and unopened bags of two brands of frozen vegetables

– One frozen vegetable mix brand from an ill person’s home in California

– Routine retail samples of another brand of frozen peas and frozen corn in Ohio

Both brands produced by the same firm

– Received frozen vegetables from the Oregon processing facility where Listeria was identified in the environment


100

90807060504030

Key

WA___21839

FCF__CFSAN048716

MD___MDA15105251

CT___593866001

FCF__CFSAN048717

LAC__H1789

CA2__F1605001-001P1A1

CA2__F1605001-003P2A1

VA___R140216044

FCF__CFSAN034726

CA___M16X00841

FCF__CFSAN034724

OH___2016001349

CASC_15SCPH22581

FCF__CFSAN048715

FCF__950087 - 103 - 150

FCF__950087 - 104 - 164

CA___M13X04892

CA___M15X00855

OH___2016001350

CA2__F1605001-004P2B2

CA___M16X01445

CA2__F1605001-002P1B1

FCF__950087 - 45 - 036

FCF__950087 - 44 - 026

FCF__950087 - 55 - 066

FCF__950087 - 57 - 086

FCF__950087 - 98 - 140

FCF__950087 - 80 - 171

FCF__950087 - 56 - 076

FCF__950087 - 41 - 006

FCF__950087 - 106 - 176

FCF__949810 - 07 - 06

FCF__950087 - 95 - 126

FCF__949810 - 20 - 16

FCF__950087 - 43 - 016

FCF__950087 - 46 - 046

FCF__950087 - 47 - 056

FCF__949810 - 21 - 21

FCF__950087 - 93 - 116

Modified date

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

cdc_id

2015L-6917

2015L-6853

2015L-6031

2014L-6089

2016L-6104

2015L-6840

2013L-5546

2015L-6129

WGS_id

PNUSAL001967

CFSAN048716

PNUSAL001711

PNUSAL002184

CFSAN048717

PNUSAL001261

CFSAN051145

CFSAN051149

PNUSAL000599

CFSAN034726

PNUSAL002066

CFSAN034724

PNUSAL002151

PNUSAL001882

CFSAN048715

FDA00010055

FDA00010059

PNUSAL000297

PNUSAL001381

PNUSAL002152

CFSAN051152

PNUSAL002137

CFSAN051147

FDA00010046

FDA00010045

FDA00010049

FDA00010051

FDA00010054

FDA00010057

FDA00010050

FDA00010044

FDA00010058

FDA00010033

FDA00010053

FDA00010034

FDA00010056

FDA00010047

FDA00010048

FDA00010035

FDA00010052

PFGE-AscI-pattern

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0101

GX6A16.0101

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0051

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

PFGE-ApaI-pattern

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.0874

GX6A12.0874

GX6A12.0001

GX6A12.0001

GX6A12.0001

GX6A12.0001

GX6A12.0001

GX6A12.0001

GX6A12.0001

GX6A12.0001

GX6A12.2670

GX6A12.2194

GX6A12.2194

GX6A12.0001

GX6A12.0070

GX6A12.0070

GX6A12.0070

GX6A12.0001

GX6A12.0001

Outbreak

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

Serotype

1/2a

not typed

1/2a

not typed

not typed

1/2a

1/2a

not typed

1/2a

not typed

not typed

1/2a

not typed

not typed

not typed

1/2a

1/2a

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

IsolatDate

2015-12-11

2015-07-19

2015-07-06

2016-05-03

2015-07-19

2015-01-03

2014-02-05

2014-11-25

2016-01-18

2014-11-25

2016-04-11

2015-10-29

2015-07-19

2016-03-09

2016-03-09

2013-09-13

2015-02-16

2016-04-11

2016-03-28

2016-03-09

2016-03-09

2016-03-09

2016-03-09

2016-03-09

2016-03-09

2016-03-09

2016-03-09

2016-03-09

2016-03-08

2016-03-09

2016-03-08

2016-03-09

2016-03-09

2016-03-09

2016-03-08

2016-03-09

ReceivedDate

2015-12-17

2015-09-01

2016-05-09

2015-01-26

2014-02-15

2014

2016-02-25

2014

2016-04-22

2015-11-06

2013-09-25

2015-03-03

2016-04-22

2016-04-11

UploadDate

2015-12-21

2015

2015-09-03

2016-05-12

2015

2015-01-28

2014-02-19

2014

2016-03-01

2014

2016-04-26

2015-11-09

2015

2016-03-25

2016-03-25

2013-09-30

2015-03-09

2016-04-26

2016-04-13

2016-03-24

2016-03-24

2016-03-24

2016-03-24

2016-03-24

2016-03-25

2016-03-24

2016-03-24

2016-03-25

2016-03-21

2016-03-24

2016-03-21

2016-03-25

2016-03-24

2016-03-24

2016-03-21

2016-03-24

SourceCountry

.

.

.

.

.

.

.

.

.

.

.

.

.

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.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

SourceState

.

.

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.

.

.

.

.

.

.

.

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.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

SourceType

.

.

.

.

.

.

.

.

.

.

.

.

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.

.

.

.

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.

.

.

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.

.

.

.

.

.

.

.

.

.

.

.

.

SourceSite

Blood, NOS

Green beans

Blood

Blood

Green beans

Blood

Other

Onions

Blood

Onions

White Sweet Corn

Blood

Green beans

Environmental Swab

Environmental Swab

Abdominal Fluid

Blood

Petite Green Peas

Blood

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

6[0-16]

7.5[0-9]

>2000

11[0-27]


100

90807060504030

Key

WA___21839

FCF__CFSAN048716

MD___MDA15105251

CT___593866001

FCF__CFSAN048717

LAC__H1789

CA2__F1605001-001P1A1

CA2__F1605001-003P2A1

VA___R140216044

FCF__CFSAN034726

CA___M16X00841

FCF__CFSAN034724

OH___2016001349

CASC_15SCPH22581

FCF__CFSAN048715

FCF__950087 - 103 - 150

FCF__950087 - 104 - 164

CA___M13X04892

CA___M15X00855

OH___2016001350

CA2__F1605001-004P2B2

CA___M16X01445

CA2__F1605001-002P1B1

FCF__950087 - 45 - 036

FCF__950087 - 44 - 026

FCF__950087 - 55 - 066

FCF__950087 - 57 - 086

FCF__950087 - 98 - 140

FCF__950087 - 80 - 171

FCF__950087 - 56 - 076

FCF__950087 - 41 - 006

FCF__950087 - 106 - 176

FCF__949810 - 07 - 06

FCF__950087 - 95 - 126

FCF__949810 - 20 - 16

FCF__950087 - 43 - 016

FCF__950087 - 46 - 046

FCF__950087 - 47 - 056

FCF__949810 - 21 - 21

FCF__950087 - 93 - 116

Modified date

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

cdc_id

2015L-6917

2015L-6853

2015L-6031

2014L-6089

2016L-6104

2015L-6840

2013L-5546

2015L-6129

WGS_id

PNUSAL001967

CFSAN048716

PNUSAL001711

PNUSAL002184

CFSAN048717

PNUSAL001261

CFSAN051145

CFSAN051149

PNUSAL000599

CFSAN034726

PNUSAL002066

CFSAN034724

PNUSAL002151

PNUSAL001882

CFSAN048715

FDA00010055

FDA00010059

PNUSAL000297

PNUSAL001381

PNUSAL002152

CFSAN051152

PNUSAL002137

CFSAN051147

FDA00010046

FDA00010045

FDA00010049

FDA00010051

FDA00010054

FDA00010057

FDA00010050

FDA00010044

FDA00010058

FDA00010033

FDA00010053

FDA00010034

FDA00010056

FDA00010047

FDA00010048

FDA00010035

FDA00010052

PFGE-AscI-pattern

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0397

GX6A16.0101

GX6A16.0101

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0051

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

GX6A16.0001

PFGE-ApaI-pattern

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.1067

GX6A12.0874

GX6A12.0874

GX6A12.0001

GX6A12.0001

GX6A12.0001

GX6A12.0001

GX6A12.0001

GX6A12.0001

GX6A12.0001

GX6A12.0001

GX6A12.2670

GX6A12.2194

GX6A12.2194

GX6A12.0001

GX6A12.0070

GX6A12.0070

GX6A12.0070

GX6A12.0001

GX6A12.0001

Outbreak

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

1603CAGX6-1WGS

Serotype

1/2a

not typed

1/2a

not typed

not typed

1/2a

1/2a

not typed

1/2a

not typed

not typed

1/2a

not typed

not typed

not typed

1/2a

1/2a

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

not typed

IsolatDate

2015-12-11

2015-07-19

2015-07-06

2016-05-03

2015-07-19

2015-01-03

2014-02-05

2014-11-25

2016-01-18

2014-11-25

2016-04-11

2015-10-29

2015-07-19

2016-03-09

2016-03-09

2013-09-13

2015-02-16

2016-04-11

2016-03-28

2016-03-09

2016-03-09

2016-03-09

2016-03-09

2016-03-09

2016-03-09

2016-03-09

2016-03-09

2016-03-09

2016-03-08

2016-03-09

2016-03-08

2016-03-09

2016-03-09

2016-03-09

2016-03-08

2016-03-09

ReceivedDate

2015-12-17

2015-09-01

2016-05-09

2015-01-26

2014-02-15

2014

2016-02-25

2014

2016-04-22

2015-11-06

2013-09-25

2015-03-03

2016-04-22

2016-04-11

UploadDate

2015-12-21

2015

2015-09-03

2016-05-12

2015

2015-01-28

2014-02-19

2014

2016-03-01

2014

2016-04-26

2015-11-09

2015

2016-03-25

2016-03-25

2013-09-30

2015-03-09

2016-04-26

2016-04-13

2016-03-24

2016-03-24

2016-03-24

2016-03-24

2016-03-24

2016-03-25

2016-03-24

2016-03-24

2016-03-25

2016-03-21

2016-03-24

2016-03-21

2016-03-25

2016-03-24

2016-03-24

2016-03-21

2016-03-24

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SourceSite

Blood, NOS

Green beans

Blood

Blood

Green beans

Blood

Other

Onions

Blood

Onions

White Sweet Corn

Blood

Green beans

Environmental Swab

Environmental Swab

Abdominal Fluid

Blood

Petite Green Peas

Blood

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Environmental Swab

Final WGS Results Initial 8 patient isolates

Initial 2 environmental isolates from the frozen fruit and vegetable processor

Frozen vegetable products • Leftover from CA patient • Routine product sampling in OH

Frozen vegetable products • Leftover from CA patient • Routine product sampling in OH

9th patient isolate

Additional environmental isolates from the frozen fruit and vegetable processor (no clinical isolates)

Resolution of the Outbreak

Relatively small number of illnesses led to recalls of 456 products sold under 42 brands

– Recalled products not limited to frozen vegetables and fruits, and included foods like prepared salads, frozen meals, frozen snack foods

However, if this had not been identified, low numbers of illnesses could likely have continued indefinitely

Were not able to obtain good information on how these food were prepared

– Microwaving vs cooking?

– Eaten raw or used in smoothies?

CONCLUSIONS

Emerging Trends in Listeriosis Outbreaks

Many novel vehicles identified since implementation of WGS in 2013

Caramel apples

Ice cream

Frozen vegetables

Bagged salad mix

Outbreaks continue to be linked to cheese, primarily from domestically produced pasteurized milk cheeses

Notable absence of hot dogs/deli meats as a source of major outbreaks over the last decade

Changing Notion of Sporadic Illness

Listeriosis linked to frozen vegetables • 9 cases in 3 years

Listeriosis linked to ice cream • 10 cases in 5 years

These illnesses are not sporadic, but are endemic disease that previously appeared sporadic because of limitations in investigation tools

Public Health Impact of WGS on Listeriosis

Outbreak Investigations

14

0 2 6 13

19

6 5 4

20 21

6 9 3

103

0

20

40

60

80

100

120

No. of clustersdetected

No. of clustersdetected

sooner or onlyby WGS

No. ofoutbreaks

solved(food source

identified)

Median no. ofcases percluster oroutbreak

No. of caseslinked to food

source

Pre-WGS (Sept 2012–Aug 2013)

WGS Year 1 (Sept 2013–Aug 2014)

WGS Year 2 (Sept 2014–Aug 2015)

Summary

WGS has already improved our ability to detect, triage, investigate, and solve outbreaks of Listeria monocytogenes infections

More outbreaks found

Identified when they are smaller

Begin the investigation with better “leads”

Hopefully stopped sooner, before they become catastrophic (e.g., 2011 cantaloupe outbreak)

The vast majority of listeriosis in the US is still not linked to a known outbreak

The next steps in preventing illness will need to target what have, until now, appeared to be sporadic illnesses

Control of Listeria monocytogenes in Ready-to-Eat Foods ...

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