FSIS FSIS Listeria Listeria Risk Risk AssessmentAssessment

Daniel GallagherDaniel GallagherDept. of Dept. of Civil & Environmental & Environmental

EngineeringEngineeringVirginia TechVirginia Tech

Eric Ebel and Janell KauseFSIS Risk Assessment Division

USDA

Listeria Public MeetingFebruary 26, 2003

OverviewOverview

FDA FDA ListeriaListeria risk ranking of RTE products risk ranking of RTE products

FSIS Risk Management QuestionsFSIS Risk Management Questions

FSIS FSIS Listeria Listeria Risk Assessment ModelRisk Assessment Model

Data Inputs and AssumptionsData Inputs and Assumptions

Model ImplementationModel Implementation

Risk Assessment OutputsRisk Assessment Outputs

Summary of FindingsSummary of Findings

FDA Risk Ranking of RTE ProductsFDA Risk Ranking of RTE Products

Food Category

Deli M

eats

Deli S

alads

Past.

Milk

Frank

furte

rs

Misc

Dair

y

Smok

ed S

eafo

od

Soft C

hees

e

Mea

t Spr

eads

CRTEC

HTNC

Med

ian

Num

ber

of L

iste

rioso

s C

ases

0

200

400

600

800

1000

1200

1400

1600

Approach: Relative Risk Approach: Relative Risk Ranking of Food Ranking of Food CategoriesCategories

Purpose: Identify foods Purpose: Identify foods that pose the greatest that pose the greatest public health risk and public health risk and focus resources focus resources accordinglyaccordingly

Evaluated Lm from retail Evaluated Lm from retail to public healthto public health

Available public commentAvailable public comment

Version 2 to be releasedVersion 2 to be released

FSIS FSIS Listeria Listeria Risk Management Risk Management QuestionsQuestions

Examine the effectiveness of testing and Examine the effectiveness of testing and sanitation of food contact surfaces on mitigating sanitation of food contact surfaces on mitigating product contamination, and reducing the product contamination, and reducing the subsequent risk of illness subsequent risk of illness

Evaluate the effectiveness of other interventions Evaluate the effectiveness of other interventions (e.g., pre- and post-packaging interventions)(e.g., pre- and post-packaging interventions)

Provide guidance on how frequently to test and Provide guidance on how frequently to test and sanitize food contact surfaces for sanitize food contact surfaces for ListeriaListeria spp. spp.

Possible Sources of Lm in RTE Possible Sources of Lm in RTE Products at RetailProducts at Retail

Inadequate lethality during processingInadequate lethality during processing

Direct deposition from non-food contact Direct deposition from non-food contact surfacesurface

Transfer from food contact surfaceTransfer from food contact surface

Focus on food contact surfaces as the source of Lm

Model DescriptionModel Description

Dynamic “in-plant” Dynamic “in-plant” Monte CarloMonte Carlo model model predicts Lm concentrations at retailpredicts Lm concentrations at retail

Coupled with an updated version of the FDA Coupled with an updated version of the FDA ListeriaListeria risk assessment model to predict risk assessment model to predict human health impactshuman health impacts

Mass balance approach –track bacteria as Mass balance approach –track bacteria as move from one media to anothermove from one media to another

Incorporates FCS testing, product testing, Incorporates FCS testing, product testing, sanitation, pre- and post-packaging sanitation, pre- and post-packaging interventions, growth inhibitors interventions, growth inhibitors

Conducted on deli meats (“high risk”)Conducted on deli meats (“high risk”)

Con

cept

ual M

odel

,P

art 1

Con

tam

inat

ion

Eve

ntTime and Duration

Fre

quen

cy

Number of Lspp Organisms

Food ContactSurface

RTE Productbefore post-processing

transfercoefficient

Con

cent

ratio

nof

Lm

Concentration ofListeria Spp

L spp Testing& Sanitation

on FoodContactSurface

Positive? ApplyCorrective action

Listeria Reservoir(niches, harborage sites, drains, …)

ContaminationEvent

Con

cept

ual M

odel

,P

art 2

transport to retail:EGR, packaging

Distribution atretail for FDA/FSIS model

Post-processingcontrols

RTE Productafter post-processing

RTE producttesting Positive?

Dispose

Risk Assessment OutputsRisk Assessment Outputs

The risk of illness or death on a per annum basis The risk of illness or death on a per annum basis from Lm in deli meat as a function of:from Lm in deli meat as a function of:

– Testing (Testing (Listeria Listeria spp.) and sanitation frequency spp.) and sanitation frequency (based on plant size) of food contact surfaces(based on plant size) of food contact surfaces

– Testing (Lm) and disposition of RTE productTesting (Lm) and disposition of RTE product

– Pre- and post-packaging interventionsPre- and post-packaging interventions

The likelihood of detecting Lm in a product lot if The likelihood of detecting Lm in a product lot if a FCS tests positive for a FCS tests positive for Listeria Listeria spp.spp.

Key Data RequirementsKey Data Requirements

Contamination EventsContamination Events– frequency, duration, levelsfrequency, duration, levels

Transfer coefficients from FCS to productTransfer coefficients from FCS to product

Lm to Lspp ratiosLm to Lspp ratios

Line production levels by plant sizeLine production levels by plant size

Contamination Event: Contamination Event: FrequencyFrequency

Data source: FSIS IDV data Data source: FSIS IDV data

Date description: Lspp Date description: Lspp prevalence over time for prevalence over time for various food contact surfacesvarious food contact surfaces

Method: Fit with survival Method: Fit with survival analysisanalysis

Results: Log normal Results: Log normal distributiondistribution– Mean time between Mean time between

contamination events: 23.1 dayscontamination events: 23.1 days– Standard deviation: 38 daysStandard deviation: 38 days

0.50

1.50

2.50

3.50

4.50

-2.00 -1.13 -0.25 0.63 1.50

Lognormal Probability Plot

Lognormal QuantileLn(T

ime)

Contamination Event: DurationContamination Event: Duration

Data Source: Tompkin Data Source: Tompkin 20022002

Data description: Data description: Sequential weekly Lspp Sequential weekly Lspp positives for food contact positives for food contact surfacessurfaces

Method: Fit with survival Method: Fit with survival analysisanalysis

Results: log normal Results: log normal distributiondistribution– Mean: 8.8 daysMean: 8.8 days– Standard deviation: 2.1 daysStandard deviation: 2.1 days

1.80

2.20

2.60

3.00

3.40

0.40 0.70 1.00 1.30 1.60

Lognormal Probability Plot

Lognormal Quantile

Ln(T

ime)

Transfer CoefficientsTransfer Coefficients

Data Source: published literatureData Source: published literatureResults:Results:– Montville et al. (2001) and Chen et al. (2001) found Montville et al. (2001) and Chen et al. (2001) found

that transfer coefficients of bacteria were log normally that transfer coefficients of bacteria were log normally distributed. Range: 0.01% to 10% Standard distributed. Range: 0.01% to 10% Standard deviation ~ 1 logdeviation ~ 1 log

– Midelet & Carpentier (2002) found that after 12 Midelet & Carpentier (2002) found that after 12 contacts, 60%-100% of initial Lm transferred, ~100% contacts, 60%-100% of initial Lm transferred, ~100% of other bacteria.of other bacteria.

LMRA uses a log mean of –0.14 with a log SD of LMRA uses a log mean of –0.14 with a log SD of 1. Truncate to 100% at max.1. Truncate to 100% at max.

Lspp to Lm RatioLspp to Lm Ratio

Data Source: prevalence data provided in Tompkin Data Source: prevalence data provided in Tompkin (2002) and blinded industry data (no available (2002) and blinded industry data (no available ListeriaListeria level data) level data)

Assumption: prevalence ratio used for level ratioAssumption: prevalence ratio used for level ratio

Results: ratios fit (truncated) normal distributionResults: ratios fit (truncated) normal distribution– Mean: 52.6%Mean: 52.6%– Standard deviation: 26.7% Standard deviation: 26.7%

Production Levels/ Lot Volumes by Plant Production Levels/ Lot Volumes by Plant SizeSize

Data source: FSIS RTE SurveyData source: FSIS RTE Survey

Lot size per line per shift varies by plant Lot size per line per shift varies by plant size:size:– Large: 48%, 19000 lb Large: 48%, 19000 lb ± 14000± 14000– Small: 48%, 7100 lb Small: 48%, 7100 lb ±± 10600 10600– Very Small: 4%, 2800 lb Very Small: 4%, 2800 lb ± 9500± 9500

Assume that FCS area varies Assume that FCS area varies proportionately.proportionately.

Contamination EventContamination EventAdded Lspp to Food Contact Added Lspp to Food Contact

SurfaceSurfaceSource: No available data (calibrated Source: No available data (calibrated data input)data input)

Assumption: Added levels are log Assumption: Added levels are log normally distributednormally distributed

Method: Calibrate the added levels so Method: Calibrate the added levels so that the predicted Lm distribution at that the predicted Lm distribution at retail matches the FDA retail distributionretail matches the FDA retail distribution

Model CalibrationModel CalibrationFDA Lm concentration distribution at retailFDA Lm concentration distribution at retail

Prevalence of Lm in productPrevalence of Lm in product– Levine et al. (2001) found prevalence from 0.52% - Levine et al. (2001) found prevalence from 0.52% -

5.16% in RTE meat and poultry. Generally 5.16% in RTE meat and poultry. Generally decreasing with time. Generally 1-3% in 1999.decreasing with time. Generally 1-3% in 1999.

– Luchansky (in press) found 1.6% prevalence in Luchansky (in press) found 1.6% prevalence in frankfurter packagesfrankfurter packages

– NFPA (2002) found 0.9% prevalence in RTE meatNFPA (2002) found 0.9% prevalence in RTE meat

Preliminary USDA DataPreliminary USDA DataCY 2002CY 2002

HAACP code 03G (fully cooked, not shelf HAACP code 03G (fully cooked, not shelf stable)stable)

subcategory: sliced, diced, shredded (e.g. subcategory: sliced, diced, shredded (e.g. sliced ham, sliced bologna, sliced chicken sliced ham, sliced bologna, sliced chicken breast, diced chicken)breast, diced chicken)

23 Lm positives out of 997 samples23 Lm positives out of 997 samples

prevalence of 2.3%prevalence of 2.3%

Model Implementation and Model Implementation and Baseline DataBaseline Data

Data Entry Screens and Baseline DataData Entry Screens and Baseline Data

Data Entry Screens and Baseline DataData Entry Screens and Baseline Data

Data Entry Screens and Baseline DataData Entry Screens and Baseline Data

Data Entry Screens and Baseline DataData Entry Screens and Baseline Data

Data Entry Screens and Baseline DataData Entry Screens and Baseline Data

Data Entry Screens and Baseline DataData Entry Screens and Baseline Data

Output ScreensOutput Screens

Output ScreensOutput Screens

Results: Lot TimelineResults: Lot Timeline

Post processing Growth ?Post processing Growth ?FDA model assumes about 1.9 logs of growth FDA model assumes about 1.9 logs of growth on average between processing and retail.on average between processing and retail.

SourceSource % at Processing% at Processing % at Retail% at Retail

FSISFSIS 1% - 3%1% - 3%

measuredmeasured

??

NFPANFPA ?? 0.9%0.9%

measuredmeasured

LMRA uses same approach as FDA but with less LMRA uses same approach as FDA but with less growth (1 log vs 1.9 logs). Lack of variability may growth (1 log vs 1.9 logs). Lack of variability may impact growth-inhibiting-packaging conclusions.impact growth-inhibiting-packaging conclusions.

Analysis of growthAnalysis of growth

ProductionLog(Lm per gram)

GrowthLog(Growth)

=RetailLog(Lm per gram)

+

Normal(µ1,σ1) Normal(µ2,σ2) Normal(µ1+µ2, σ21 +σ2

2)+ =

Given a retail distribution,solve for production distributionfor different assumed growth distributions.

Then examine implied sample prevalence levelsassuming a test positive threshold of 1 Lm organismin 25 gram samples.

Case 1Case 1Production concentration

X >=-1.40.3%

0

0.02

0.04

0.06

0.08

0.1

0.12

-25 -20 -15 -10 -5 0 5

Log(Lm per gram)

Pro

bab

ility

=1/25=0.04 Lm per gram

Normalmean= -9.9s.d=3.2

Growth multiplier

0

0.05

0.1

0.15

0.2

0.25

0.3

-4 -2 0 2 4 6 8

Log(Growth)

Pro

bab

ility

Normalmean=1.9s.d=1.4

Retail concentrationX >=-1.4

3%

0

0.02

0.04

0.06

0.08

0.1

0.12

-25 -20 -15 -10 -5 0 5 10

Log(Lm per gram)

Pro

bab

ility

=1/25=0.04 Lm per gram

Normalmean= -8s.d=3.5

+

=

Case 2Case 2Production concentration

X >= -1.40.8%

0

0.02

0.04

0.06

0.08

0.1

0.12

-25 -20 -15 -10 -5 0 5

Log(Lm per gram)

Pro

bab

ility

NormalMean= -9.9s.d.=3.5

Growth multiplier

0

0.2

0.4

0.6

0.8

1

-2 -1 0 1 2 3 4 5

Log(Growth)

Pro

bab

ility

Scalar value= 1.9

Retail concentrationX >= -1.4

3%

0

0.02

0.04

0.06

0.08

0.1

0.12

-25 -20 -15 -10 -5 0 5 10

Log(Lm per gram)

Pro

bab

ility

=1/25=0.04 Lm per gram

Normalmean=-8s.d=3.5

+

=

Case 3Case 3Production concentration

X >= -1.41.5%

0

0.02

0.04

0.06

0.08

0.1

0.12

-25 -20 -15 -10 -5 0 5

Log(Lm per gram)

Normalmean= -9s.d.=3.5

Growth multiplier

0

0.2

0.4

0.6

0.8

1

-2 -1 0 1 2 3 4 5

Log(Growth)

Pro

bab

ility

Scalar value= 1.0

Retail concentrationX >=-1.4

3%

0

0.02

0.04

0.06

0.08

0.1

0.12

-25 -20 -15 -10 -5 0 5 10

Log(Lm per gram)

Pro

bab

ility

=1/25=0.04 Lm per gram

Normalmean= -8s.d=3.5

+

=

Mass Balance: Tracking Lspp on FCS

Lspp

Add

ed (

cfu/

cm2 )

1e-12

1e-11

1e-10

1e-9

1e-8

1e-7

1e-6

1e-5

1e-4

1e-3

1e-2

1e-1

1e+0

Lspp

on

FC

S a

t end

of L

ot(c

fu/c

m2 )

1e-13

1e-12

1e-11

1e-10

1e-9

1e-8

1e-7

1e-6

1e-5

1e-4

1e-3

1e-2

1e-1

Lot No.

90 100 110 120 130

Lm in

Pro

duct

(cfu

/g)

1e-161e-151e-141e-131e-121e-111e-101e-91e-81e-71e-61e-51e-41e-31e-2

Model EvaluationModel Evaluation

Comparison of FSIS Model Outputs to Comparison of FSIS Model Outputs to FDA Risk Assessment InputsFDA Risk Assessment Inputs

Percentile

75 80 85 90 95 100 105

Lm in

RT

E p

rodu

ct a

t ret

ail

(cfu

/g)

1e-7

1e-6

1e-5

1e-4

1e-3

1e-2

1e-1

1e+0

1e+1

1e+2

1e+3

1e+4

1e+5

1e+6FDA

LMRA Calibration

Baseline predictionsBaseline predictions

Calibration to “average” Calibration to “average” updated FDA/FSIS updated FDA/FSIS model Lm model Lm concentration in retail concentration in retail deli meat distributiondeli meat distribution

Lack of uncertainty Lack of uncertainty about concentration about concentration has small effect on has small effect on uncertainty about public uncertainty about public health predictionshealth predictions

In-plant baseline In-plant baseline predictions repeatablepredictions repeatable

0

50

100

150

200

250

300

350

OriginalFDA/FSIS

FDA/FSISmodified 1

Baseline 1 Baseline 2

Scenario

Dea

ths

in e

lder

ly p

er a

nn

um

Lm. Concentration uncertainty included

Lm. Concentration uncertainty NOT

included

In-plant model output calibrated to FDA/FSIS

model

Median, 5Median, 5thth and 95 and 95thth percentiles percentilesin predicted elderly deathsin predicted elderly deaths

Variability of 20 runs of 4-2-1 scenario(1,000,000 lots per run)

Percentiles

Lm C

onc

entr

atio

n a

t Ret

ail

1e-7

1e-6

1e-5

1e-4

1e-3

1e-2

1e-1

1e+0

1e+1

1e+2

1e+3

1e+4

1e+5

1e+6

1e+7

Q80 Q99 Q99.99

Model StabilityModel Stability

Model ResultsModel Results

Scenarios TestedScenarios TestedBaseline calibration: no testing, no interventions, no post-processing, no Baseline calibration: no testing, no interventions, no post-processing, no GIPGIPFCS Testing Levels, test and hold yes, dispose product yes, test lot yes, FCS Testing Levels, test and hold yes, dispose product yes, test lot yes, enhanced cleaning yes (No. tests per line per month for large, small, very enhanced cleaning yes (No. tests per line per month for large, small, very small plants)small plants)– 4-2-14-2-1– 8-4-28-4-2– 10-10-1010-10-10– 16-8-416-8-4– 32-16-832-16-8– 60-60-6060-60-60

60-60-60 Lot testing, dispose product yes60-60-60 Lot testing, dispose product yes100% post-processing treatment (90% - 95% effective) for all three plant 100% post-processing treatment (90% - 95% effective) for all three plant sizes, no testingsizes, no testing100% growth-inhibiting packaging (90% 95% effective) for all three plant 100% growth-inhibiting packaging (90% 95% effective) for all three plant sizes, no testingsizes, no testing

All scenarios tested for production of 1,000,000 lots.

Scenario

FDA

Baselin

e4-2-1

8-4-2

10-10-1016-8-4

32-16-8

40-20-10

60-60-60

60-60-60 LotPP

GIP

PP & GIP

Lm C

once

ntra

tion

at R

eta

il(c

fu/g

)

1e-9

1e-8

1e-7

1e-6

1e-5

1e-4

1e-3

1e-2

1e-1

1e+0

1e+1

1e+2

1e+3

1e+4

1e+5

1e+6

1e+7Q80 Q99 Q99.99

FCS Testing/Sanitation ImpactsFCS Testing/Sanitation Impacts

Contingency Table: Likelihood of Contingency Table: Likelihood of Detecting Detecting Listeria Listeria spp./Lmspp./Lm

Overall FCS prevalence of ~ 13.7%Overall FCS prevalence of ~ 13.7%

Overall Lot prevalence of ~2.2%Overall Lot prevalence of ~2.2%

Lot prevalence when FCS is positive ~15.7%Lot prevalence when FCS is positive ~15.7%

FCS testing improves lot testing by factor of 7FCS testing improves lot testing by factor of 7

60-60-60 FCS tests, 60-60-60 lot tests, test and hold in place

RTE + RTE - SumFCS + 21635 115940 137575FCS - 8 862417 862425Sum 21643 978357 1000000

Test and Hold ComparisonTest and Hold Comparison

Scenario

4-2-1 T&H

4-2-1 No T&H

8-4-2 T&H

8-4-2 No T&H

16-8-4 T&H

16-8-4 No T&H

32-16-8 T&H

32-16-8 No T&H

60-60-60 T&H

60-60-60 No T&H

LM

Co

nce

ntr

atio

n a

t Re

tail

(cfu

/g)

1e-7

1e-6

1e-5

1e-4

1e-3

1e-2

1e-1

1e+0

1e+1

1e+2

1e+3

1e+4

1e+5

1e+6

1e+7Q80 Q99 Q99.99

Test and Hold EvaluationTest and Hold Evaluation

Overall FCS prevalence approximately constant at Overall FCS prevalence approximately constant at ~13-14 % regardless of test and hold.~13-14 % regardless of test and hold.

Overall lot prevalence 15-16% if test and hold, 4-5% Overall lot prevalence 15-16% if test and hold, 4-5% if not test and holdif not test and hold

Recall overall lot prevalence ~2.2%Recall overall lot prevalence ~2.2%

For retail Lm, test and hold only significant at more For retail Lm, test and hold only significant at more frequent FCS testingfrequent FCS testing

FCS Sample

Frequency

Test and Hold?

FCS Tests

FCS Positives

Lot Tests Lot Positives

% FCS Positives

% Lot Positives

4 Yes 66667 9171 9171 1432 13.8 15.6 4 No 66666 9442 9442 422 14.2 4.5

60 Yes 1000000 132914 132914 20560 13.3 15.5 60 No 1000000 131867 131867 5268 13.2 4.0

Sensitivity AnalysisSensitivity Analysis

Sensitivity Sensitivity Analysis: Analysis: Sampled Sampled

RTE MassRTE MassLM

Con

cent

ratio

n at

Ret

ail (

cfu/

g)

10-7

10-6

10-5

10-4

10-3

10-2

10-1

100

101

Q80 Q99 Q99.99

60-60-60 Lot testing, test and hold, dispose product

RTE Sample Mass (grams)

25 50 100 200 400 800

Per

cent

Lot

s P

ositi

ve (

%)

0

1

2

3

4

5

Sensitivity Analysis: FCS Area TestedSensitivity Analysis: FCS Area Tested

Sampled Surface Area (cm2)

0.01 0.1 1 10 100 1000 10000

Lm

Co

ncen

tra

tion

at R

eta

il (c

fu/g

)

10-7

10-6

10-5

10-4

10-3

10-2

10-1

100

101

102

103

Q80 Q99 Q99.99

60-60-60 FCS Testing, enhanced cleaning, test lot, dispose lot

Sensitivity Sensitivity Analysis: FCS Analysis: FCS Area TestedArea Tested

No.

FC

S P

ositi

ves

= N

o. L

ots

Tes

ted

No.

Lot

Pos

itive

s

0.0

2.0e+4

4.0e+4

6.0e+4

8.0e+4

1.0e+5

1.2e+5

1.4e+5

1.6e+5

1.8e+5FCS Positives = Lots TestedLot Fails

FCS Surface Area Tested (cm2)

0.01 0.1 1 10 100 1000 10000P

erce

nt F

CS

Pos

itive

s (%

)

0

2

4

6

8

10

12

14

16

FCS Surface Area Tested (cm2)

0.01 0.1 1 10 100 1000 10000

Per

cent

of T

este

d Lo

ts P

ositi

ve (

%)

0

20

40

60

80

60-60-60 FCS Testing, enhanced cleaning, test lot, dispose lot

Sensitivity Analysis: Post processingSensitivity Analysis: Post processing

Post processing (Industry participation, effectiveness)

LM c

once

ntr

atio

n at

ret

ail (

cfu/

g)

10-9

10-8

10-7

10-6

10-5

10-4

10-3

10-2

10-1

100

101

102

103

104

105

106

80.00% 99.00% 99.99%

70-75% Effective 90-95% Effective 99% Effective

50% 75% 90% 100% 50% 75% 90% 100% 50% 75% 90% 100% % IndustryParticiparting

No FCS testing, no lot testing

Evaluation of prevalence for Evaluation of prevalence for different Lm/Lspp ratiosdifferent Lm/Lspp ratios

Parameter Low Ratio Baseline High Ratio Mean Lm/Lspp ratio 0.052 0.52 0.95 Std dev Lm/Lspp ratio 0.026 0.26 0.026 Mean Lspp/cm2 added during contamination event (log scale)

-5 -6 -6.4

Std dev Lspp/cm2 added 3.5 3.5 3.5 overall lot prevalence (%) 2.2 2.2 2.0 overall FCS prevalence (%) 18.7 13.8 12.0 contingent lot prevalence when FCS is positive (%)

11.7 15.7 17.0

Improvement 5.3 7.1 8.5

Each new ratio requires a recalibration to match the observed Lm distribution at retail. These results are preliminary

Sensitivity Analysis FindingsSensitivity Analysis Findings

RTE sampled mass, RTE sampled mass, retail Lm retail Lm– Mass should be limited only by lab Mass should be limited only by lab

considerations.considerations. FCS area sampled, FCS area sampled, retail Lm retail Lm– Caution: assumes Lm evenly distributedCaution: assumes Lm evenly distributedFCS testing is effective for a wide range of FCS testing is effective for a wide range of Lm/Lspp ratios. The effectiveness is higher at Lm/Lspp ratios. The effectiveness is higher at higher ratios.higher ratios. Post processing & industry participation, Post processing & industry participation, retail Lmretail Lm

Public Health ImpactsPublic Health Impacts

0

50

100

150

200

250

300B

asel

ine

4-2-

1

8-4-

210

-10-

1016

-8-4

32-1

6-8

40-2

0-10

60-6

0-60

60-6

0-60

RTE

PP

-95%

PP

-99% GIP

PP

-95%

& G

IP

Scenarios

Eld

erl

y d

ea

ths

pe

r a

nn

um

; M

ed

ian

Pre

dic

tio

ns

Predicted elderly deaths from deli meats

0

10

20

30

40

50

60

Baseli

ne4-

2-1

40-2

0-10

60-6

0-60

60-6

0-60

RTE

PPGIP

PP & G

IP

Scenarios

Inte

rmed

iate

ag

e d

eath

s p

er a

nn

um

; M

edia

n P

red

icti

on

s

Predicted intermediate age deaths from Predicted intermediate age deaths from

deli meatsdeli meats

Predicted neonatal deaths from Predicted neonatal deaths from deli meats deli meats

0

2

4

6

8

10

12

14

16

Baseline 4-2-1 40-20-10 60-60-60 60-60-60RTE

PP & GIP

Scenarios

Neo

nat

al d

eath

s p

er a

nn

um

; M

edia

n P

red

icti

on

s

Predicted lives saved relative to baseline

ScenarioScenario ElderlyElderly IntermediateIntermediate NeonatesNeonates TotalTotal

4-2-1 20 4 1 25

8-4-2 30 ? ? 30

10-10-10 40 ? ? 40

16-8-4 30 ? ? 30

32-16-8 60 ? ? 60

40-20-10 70 15 4 89

60-60-60 120 27 7 154

60-60-60 RTE 120 26 7 153

PP-95% 120 26 ? 146

PP-99% 173 39 10 221

GIP 110 25 ? 135

PP-95% & GIP 186 41 11 238

Test and control combinationsTest and control combinations

050

100150200250300

Bas

elin

e4-

2-1

4-2-

1 P

P4-

2-1G

IP4-

2-1

PP

&G

IP32

-16-

832

-16-

8 P

P32

-16-

8 G

IP32

-16-

8 P

P&

GIP

60-6

0-60

60-6

0-60

PP

60-6

0-60

GIP

60-6

0-60

PP

&G

IP

Scenarios

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Note: Testing is non-additive with post-processing treatment.

Model VariablesModel Variables

Only considers food contact surface as Only considers food contact surface as source of Lspp/Lm in productsource of Lspp/Lm in product

Only a “generic” food contact surfaceOnly a “generic” food contact surface

Assumes Lspp evenly distributed across Assumes Lspp evenly distributed across food contact surface, and Lm evenly food contact surface, and Lm evenly distributed within productdistributed within product

Operates on a product lot basisOperates on a product lot basis

Summary FindingsSummary FindingsFood contact surfaces found to be positive for Food contact surfaces found to be positive for Listeria Listeria species species greatly increased the likelihood of finding RTE product lots greatly increased the likelihood of finding RTE product lots positive for Lm (x7 if test and hold, x2 if not) ).positive for Lm (x7 if test and hold, x2 if not) ).

Frequency of contamination of FCS with Frequency of contamination of FCS with Listeria Listeria species appears species appears to encompass a broad timeframe, and the duration of to encompass a broad timeframe, and the duration of contamination lasts about a week.contamination lasts about a week.

The proposed minimal frequency of FCS testing/sanitation, as The proposed minimal frequency of FCS testing/sanitation, as presented in the proposed rule (66 FR 12589, Feb. 27, 2001) presented in the proposed rule (66 FR 12589, Feb. 27, 2001) results in a small reduction in the levels of Lm in deli meats at results in a small reduction in the levels of Lm in deli meats at retail.retail.

Increased frequency of testing/sanitation leads to proportionally Increased frequency of testing/sanitation leads to proportionally lower risk of listeriosis. lower risk of listeriosis.

Combinations of interventions appear to be much more effective Combinations of interventions appear to be much more effective than any single intervention in mitigating the potential than any single intervention in mitigating the potential contamination of RTE product with Lm and reducing the contamination of RTE product with Lm and reducing the subsequent risk of illness or death.subsequent risk of illness or death.

Questions?

Testing Q80 Q85 Q90 Q95 Q99 Q99.5 Q99.9 Q99.99FDA 7.40E-06 3.70E-05 2.70E-04 5.50E-03 1.50E+00 1.10E+01 7.90E+02 1.40E+05

Baseline 2.95E-06 2.66E-05 3.06E-04 8.86E-03 2.60E+00 1.78E+01 8.04E+02 2.06E+054-2-1 1.50E-06 1.57E-05 2.07E-04 6.47E-03 2.47E+00 2.20E+01 1.70E+03 3.53E+058-4-2 1.15E-06 1.25E-05 1.70E-04 5.34E-03 1.98E+00 1.70E+01 1.24E+03 3.31E+05

10-10-10 1.18E-06 1.25E-05 1.65E-04 4.78E-03 1.45E+00 1.33E+01 1.23E+03 2.53E+0516-8-4 1.39E-06 1.41E-05 1.81E-04 5.05E-03 1.40E+00 1.27E+01 1.01E+03 1.80E+0532-16-8 8.38E-07 8.98E-06 1.18E-04 3.19E-03 5.26E-01 4.50E+00 4.52E+02 7.76E+04

40-20-10 8.68E-07 9.02E-06 1.09E-04 2.71E-03 3.42E-01 2.61E+00 3.02E+02 5.62E+0460-60-60 6.29E-07 6.13E-06 6.88E-05 1.35E-03 6.10E-02 1.47E-01 5.04E-01 1.25E+00

60-60-60 Lot 7.67E-07 7.52E-06 8.34E-05 1.53E-03 6.51E-02 1.54E-01 5.08E-01 1.31E+00PP 1.12E-07 1.18E-06 1.59E-05 5.22E-04 2.03E-01 1.70E+00 1.39E+02 2.47E+04GIP 1.22E-07 1.25E-06 1.69E-05 5.60E-04 2.24E-01 1.90E+00 1.47E+02 2.09E+04

PP & GIP 8.67E-09 9.06E-08 1.23E-06 3.93E-05 1.56E-02 1.32E-01 1.08E+01 1.67E+03

Retail Concentrations of Lm (cfu/g)

Lm Distributions at Retail for Lm Distributions at Retail for Scenarios TestedScenarios Tested

Testing 5% 50% 95% AverageBaseline 79 250 290 220

4-2-1 73 230 270 2108-4-2 70 220 260 200

10-10-10 67 210 250 19016-8-4 69 220 260 20032-16-8 61 190 230 170

40-20-10 58 180 210 17060-60-60 42 130 150 120

60-60-60 Lot 43 130 160 120PP 43 130 160 120GIP 43 140 160 120

PP & GIP 21 64 76 59

Deaths Among the Elderly

Health Impacts for Scenarios Health Impacts for Scenarios TestedTested