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Outcomes Analysis of E. coli O157:H7 Vaccination in Beef Cattle
 

Outcomes Analysis of E. coli O157:H7 Vaccination in Beef Cattle

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  • Add the following slide to here
  • You will never score a touchdown by penalties.Definition of insanity – continuing to do the same thing and expecting a different result
  • Modeled some of the known NONLINEAR relationships
  • We simulated at different levels of vaccine adoption by producers, and 3 different scenarios; no vaccination, a two dose scenario (45% reduction in cattle prevalence) and a three dose scenario (80% reduction). Additionally, we simulated for various levels of production adoption from 100% to 0.
  • Explain AxesScenario A – get nonlinearAny diff from Withee??The results indicate that on average 2,000 to 3,600 cattle have to be vaccinated to prevent one E. coli O157 :H7 illness depending on the number of doses per animal.  The highlighting is just a not to myself for making up the Exec Summary
  • Explain AxesScenario A – get nonlinearAny diff from Withee??The results indicate that on average 2,000 to 3,600 cattle have to be vaccinated to prevent one E. coli O157 :H7 illness depending on the number of doses per animal.  The highlighting is just a not to myself for making up the Exec Summary
  • Recall we modeled the effect of vaccine to decrease prevalence and concentration in feces. Obviously, decreasing concentration will decrease the prevalence of positive animals as concentration nears the lower detection limit. At this point our analysis is not able to discriminate those two phenomenon. Additionally, we note that modeling more complex factors such as impact of vaccination over multiple production cycles on the feedlot environment or system may show nonlinearity in the relationship between the number of cattle vaccinated and the number of human E. coli O157:H7 cases.
  • REGULATORYThe plant’s risk of FSIS detecting one or more positive O157:H7 samples via routine testing can also be diminished. Based on current routine FSIS testing scenarios, the average large plant has about a 0.35% chance that FSIS will detect a positive sample. If all the plant’s suppliers use the three dose scenario, the risk will be reduced to virtually zero (Figure 2).Results are averaged = hypothetical large plant in US.
  • The number of events where multiple O157:H7 illnesses (outbreaks) might occur from a single production lot can be reduced by appropriate vaccination use. Figure 1 shows the number of predicted outbreaks, defined as either 2, 5, or 10 illnesses from a single production lot, for the three scenariosIndustry test and hold may significantly mitigate this risk.
  • We assumed that the number (CFU) of E. coli O157:H7 in a portion of ground beef is Poisson distributed. The Poisson distribution is frequently used to model bacterial counts in a specific weight or volume of substrate. The application of Poisson distribution is appropriate when the individual CFUs of E. coli O157:H7 are randomly distributed throughout the production lot without clustering. Given the Poisson distribution, the probability of at least one CFU of E. coli O157:H7 in a specific portion of ground beef is given by 1−𝑒−𝑆22∗𝑃𝑜𝑟𝑡𝑖𝑜𝑛 𝑠𝑖𝑧𝑒 Given the 325 gm portion size used in FSIS ground beef sampling, we calculated this parameter as S23 =1−𝑒−𝑆22∗325.Cost of Hot Lot - ……………….We assumed that the number (CFU) of E. coli O157:H7 in a portion of ground beef is Poisson distributed. The Poisson distribution is frequently used to model bacterial counts in a specific weight or volume of substrate. The application of Poisson distribution is appropriate when the individual CFUs of E. coli O157:H7 are randomly distributed throughout the production lot without clustering. Given the Poisson distribution, the probability of at least one CFU of E. coli O157:H7 in a specific portion of ground beef is given by 1−𝑒^(−𝑆_22∗𝑃𝑜𝑟𝑡𝑖𝑜𝑛 𝑠𝑖𝑧𝑒) Given the 325 gm portion size used in FSIS ground beef sampling, we calculated this parameter as S23 =1−𝑒^(−𝑆_22∗325).
  • The number of a “hot” production lots (defined as more than 1,000 O157:H7 contaminated ground beef servings in a lot) can be lessened significantly with vaccination. Simulation results indicate that there is great variability in the O157:H7 numbers/concentration in a production lot. Consequently a small fraction of production lots may be contaminated to a high degree (“hot” lots). If the average large plant (e. g. > 16,000 loads/year) is producing about 140 “hot” lots per year, then a 100% acceptance of vaccine by its suppliers will reduce hot lots by 85% to 10.
  • Sasi explain to me
  • We developed a stochastic simulation model to evaluate the impact of O157:H7 vaccination on key epidemiological outcome measures. The model considered a reduction in the O157:H7 prevalence as well as concentration in cattle feces due to vaccination. The impact of this reduction on various risk outcomes was evaluated by simulating the relationships between the O157:H7 prevalence and concentration at various points in the ground beef supply chain. The uncertainty and variability associated with the O157:H7 contamination was explicitly modeled on a carcass-by-carcass basis. We simulated at different levels of vaccine adoption by producers, and 3 different scenarios; no vaccination, a two dose scenario (45% reduction in cattle prevalence) and a three dose scenario (80% reduction). Additionally, we simulated for various levels of product adoption from 100% to 0
  • We simulated at different levels of vaccine adoption by producers, and 3 different scenarios; no vaccination, a two dose scenario (45% reduction in cattle prevalence) and a three dose scenario (80% reduction). Additionally, we simulated for various levels of production adoption from 100% to 0.
  • Making causal assumption for model
  • We developed a stochastic simulation model to evaluate the impact of O157:H7 vaccination on key epidemiological outcome measures. The model considered a reduction in the O157:H7 prevalence as well as concentration in cattle feces due to vaccination. The impact of this reduction on various risk outcomes was evaluated by simulating the relationships between the O157:H7 prevalence and concentration at various points in the ground beef supply chain. The uncertainty and variability associated with the O157:H7 contamination was explicitly modeled on a carcass-by-carcass basis.

Outcomes Analysis of E. coli O157:H7 Vaccination in Beef Cattle Outcomes Analysis of E. coli O157:H7 Vaccination in Beef Cattle Presentation Transcript

  • Outcomes Analysis of E. coli O157:H7 Vaccination in Beef Cattle
    H. Scott Hurd
    College of Veterinary Medicine, Department of Production Animal Medicine
    Former Deputy Undersecretary of Food Safety, USDA
    Director of World Health Organization Collaborating Center for Risk Analysis and Hazard Surveillance and Intervention in Food Animals
    Co-Director Collaboration for Comparative Outcomes Research Evaluation (CCORE), Iowa State University, Ames IA 50011
    shurd@iastate.edu
  • Overview of Today’s Topics
    Why Does the Industry Worry About E. coli O157:H7?
    Why Does the Industry Worry About E. coli O157:H7?
    Pre-harvest Interventions Work Sometimes,But Not Other Times
    E. coli 0157:H7 Vaccination is One of Those Times That Works
    2
  • 3
    E coli O157:H7 has a litter
  • Pre-harvest Interventions Work Sometimes
    The pathogen originates solely on the farm
    Food animal is the primary host
    Pathogen does not live well outside the host
    The % of positive farms is relatively low
    Post-harvest methods are “maxed-out”
    Dealing with outlier events
    4
  • Control of Salmonella in Denmark – 10 Years Experience – Preharvest Not Most Effective
    Hurd HS, Enøe C, Sørensen L, Wachmann H, Corns SM, Bryden KM, Greiner M: Risk-based analysis of the Danish pork Salmonella program past and future. Risk Analysis. 28:2 pp 341-351, 2008
    5
    • Funded as a project of the International EpiLab
    • Danish Institute for Food and Veterinary Research (DFVF)
    • Guest Scientist at the EpiLab in Denmark,
    • Employed at the National Animal Disease Center:USDA:ARS, Ames, Iowa, USA
  • Systems Model (Simulation) of Pork Attributable Human Cases (PAHC) of Salmonellosis
    Probability of
    Carcass Swab Positive Given Herd Seroprevalence
    Category
    Distribution of
    Herds By
    Seroprevalence
    Category and Size
    Attributes Human
    Cases as aFunction of Positive Carcasses
    Production
    Module
    Slaughter
    module
    Attribution
    Module
    Pigs from Each Seroprevalence Category
    Carcass Swab Positive Pigs
    Human Cases per Year
    6
  • Historical: Combined Effect of On-farm (Pre-harvest) Changes and Abattoir (Post-harvest)
    Simulated Pork Attributable Human Cases (Total Cases)
    Significant (P <0.05) Changes in Risk Occurred 1998–2000
    7
  • Switch off the Post-harvest see Effect of On-farm (Pre-harvest) Program Only
    Simulated Pork Attributable Human Cases (Total Cases)
    Only 19% Decrease,69 Cases (P>0.05)
    8
  • Switch off the Pre-harvest Program see Abattoir (Post-harvest) Improvements Only
    Simulated Pork Attributable Human Cases (Total Cases)
    A Difference of 81 Cases (P>0.05). Due to Abattoir Improvements Only
    9
  • Future: Major Reduction in on-farm Seroprevalence (<25% for all herds)
    Distribution of Herds by Average Annual Seroprevalence
    10
  • Future: Reduce All Herds to <25% Average Annual Seroprevalence
    Attributable Human Cases
    Still End Up with 110 Cases/Year
    Cases While Steadily Improving Abattoir Methods for All On-farm Values Set at 25% or Less (AllFarm25); Reverting On-farm to 1995 Values While Keeping Abattoir Values Constant (RevF); and Continuing to Improve On-farm While Keeping Abattoir Values Constant (ImpF)
    11
  • What Else Can Be Done?Carcass Decontamination (Post-harvest)
    12
  • Pre-harvest Interventions Work Sometimes
    The pathogen originates solely on the farm
    Food animal is the primary host
    Pathogen does not live well outside the host
    The % of positive farms is relatively low
    Post-harvest methods are “maxed-out”
    Dealing with outlier events
    13
  • Pre-harvest Interventions Work Sometimes
    Post-harvest Methods Are “Maxed-out”
    • Further reduction of the mean exhausted
    • Law of diminishing returns
    Dealing with Outlier Events
    14
  • We Have MANY Post-harvest Processes in Place Which “On Average” Work Well
    15
  • Pre-harvest Methods “Maxed Out” – Law of Diminishing Returns
    Or “half the distance to the goal line”
    Diminishing utility = “meaning that the first unit of consumption of a good or service yields more utility than the second and subsequent units” (Wikipedia)
    16
  • 17
    Outlier Events – Why Do They Happen?
    Poisson Probability Distribution
    Prevalence and concentration of E. coli in cattle is not abell curve
    It is Poisson distributed
    Average is low
    Occasional HIGH levels
    “On Average”
  • 18
    When Multiple ProcessesAre Poisson Distributed
    Cattle Prevalence
    Carcass Prevalence
    Concentration
    Event Day
  • Cut-off the First Tail and Subsequent Ones Not as Likely to Occur
    Cattle Prevalence
    Carcass Prevalence
    Concentration
    19
  • Overview of Today’s Topics
    Why Does the Industry Worry About E. coli O157:H7?
    Pre-harvest Interventions Work Sometimes,But Not Other Times
    E. coli 0157:H7 Vaccination is One of Those Times That Works
    20
  • Thomson DU, Loneragen GH, Thornton AB, et al., Use of a Siderophore Receptor and Porin Proteins-Based Vaccine to Control the Burden of Eschericia coli O157:H7 in Feedlot Cattle. Foodborne Pathogens and Disease 2009; Vol. 6, Number 7, 871-877
    21
    E. coli Bacterial Extract Vaccine: Results
    E. coli 0157 Prevalence
    85% reduction in shedding
  • Thomson DU, Loneragen GH, Thornton AB, et al., Use of a Siderophore Receptor and Porin Proteins-Based Vaccine to Control the Burden of Eschericia coli O157:H7 in Feedlot Cattle. Foodborne Pathogens and Disease 2009; Vol. 6, Number 7, 871-877
    22
    E. coli Bacterial Extract Vaccine: Results
    E. coli 0157 Prevalence
    85% reduction in shedding
    98% reduction in concentration
    Log10 MPN/g
  • 23
    Consistent significant impact of vaccination on E. coli prevalence
    Every study to date has yielded a significant reduction in E. coli shedding
    Reductions from 50-85% based on protocols and E. coli challenge
  • Best Available Data
    24
    Mathematical Model “Converts” 0157:H7 Shedding Cattle to Human Illnesses
    Production
    Slaughter
    Consumption
  • How Does Vaccine Help ReduceEvent Days? -Individual Carcasses Modeled
    25
  • Scenarios Evaluated
    Additionally, Simulated for Various Levels of
    Product Adoption by Producers 0%, 40%, 80%, 100%
    26
  • Four Outcome Measures Considered
    Mean annual number of human E. coli O157:H7 illnesses due to consumption of ground beef from steers and heifers (Public Health)
    1
    Probability of detecting E. coli O157:H7 per ground beef or ground beef trim sample tested by FSIS (in a 10,000 lb lot) (Regulatory)
    2
    Mean annual number of events where multiple E. coli 0157:H7 human illnesses (outbreaks) occur due to consumption of ground beef from a single production lot (Outbreak)
    3
    Mean annual number of a “hot” production lots (hot lot = more than 1,000 E. coli O157:H7 contaminated ground beef servings from a single lot) (Event Days)
    4
    27
  • 28
    Outcome. Annual Number ofE. coli O157:H7 Illnesses
    Annual 0157 Illnesses by Efficacy an Adoption
  • Discussion of Results –Annual Number of Illnesses
    If vaccine is 80% effective and used by all producers, the projected number of cases is reduced from 20,000 to 8,000 (60% decrease)
    However, partial adoption is also useful
    80% effective with 40% adoption  23% reduction in illness
    60% effective with 80% adoption  36% reduction in illness
    29
  • Outcome. Annual E. coli O157:H7 Illnesses Decreases with Adoption
    Number of E. coli 0157:h7 Illnesses Due to Consumptionof Ground Beef from Feedlot Cattle
    30
  • Discussion of Results –Annual Number of Illnesses
    National public health utility is largely a function of adoption, not vaccine efficacy
    If 40% effective and 100% adoption there will be 40% reduction in illnesses
    31
  • Impact on Illness Due to Reduced Cattle Prevalence and Concentration on Carcass
    Distribution of Herds by Average Annual Seroprevalence
    Number of Human Cases
    Fraction Reduction in Prevalence
    Log CFU/g Reduction in Concentration of E. coli 0157: H7 in Feces
    32
  • Discussion of Results –Annual Number of Illnesses
    Illness is impacted by BOTH decreased concentration and frequency of positive carcasses (prevalence)
    Most Post-harvest methods just reduce concentration
    Evaluated by “log reduction”
    33
  • Outcome. Probability of Detection viaFSIS Sampling (Regulatory)
    Assumed FSIS testing of raw ground beef detects 1 CFUin a 325 g sample
    Based on average probability of detection per sample tested for different slaughter plants and for different production lots from the same plant
    Impact of additional industry test and hold is not considered
    34
  • Outcome. Detection by FSIS
    Probability of Regulatory Positive by Efficacy and Adoption
    35
  • Outcome. Outbreaks
    Number of lots resulting in outbreak defined as:
    >2 illnesses
    5 illnesses, or
    10 illnesses
    From a single production lot
    Assuming 100% vaccination of cattle
    Typical large plant (16,000 lots/yr)
    36
  • Number of Lots Resulting in >2, 5,or 10 Illnesses (Assuming 100% of Herds Vaccinated)
    Mean Number of Lots per YearResulting in Multiple Illnesses
    Vaccination (100% Herds), Virtually Eliminates Chance of a Large >10 Case Outbreak
    37
  • 38
    Outcome. “Hot” Production Lots
    There is a high degree of variance in the E. coli O157:H7 numbers/concentration in a production lot
    Consequently a small fraction of production lots may be contaminated to a high degree (“hot” lots), although the average load per production lot is relatively small
    We defined a production lot (10,000 lbs) containing more than 1,000 contaminated servings as “hot” lot
    Results are for hypothetical slaughter establishment producing 16,000 production lots per year
  • Prevalence and ConcentrationAre NOT Normally Distributed
    Poisson Distribution of E. coli Prevalences
    Prevalence and concentration of E. coli in cattle is not abell curve
    It is Poisson distributed
    Occasional HIGH levels
    39
  • Outcome. Hot Lots for a Plant Producing 16,000 Production Lots Per Year
    Annual Number Hot Lots for Large Plant by Efficacy and Adoption
    40
  • Outcome. Hot Lots for a Plant Producing 16,000 Production Lots Per Year
    Annual Number Hot Lots for Large Plant by Efficacy and Adoption
    41
  • 42
    Discussion of Results – Hot Lots
    All levels of efficacy and adoption reduce the risk to packer
    Full adoption of 80% effective vaccine virtually eliminates chance of Hot Lots (96% reduction)
    40% adoption of an 80% effective vaccine results in 43% reduction in probability of Hot Lots
    80% adoption of 60% effective vaccine results in 49% reduction in probability of detection by FSIS
    What is a 20%, 30%, 40% reduction in risk worth?
  • Annual Hot Lots – Vaccine Reduces Variation and Extreme Doses
    Box-Whisker Plot Comparison
    More Variation and More “Event Days”
    43
  • Impact of Vaccination on Number of ProductionLots with High E. coli 0157 Prevalence (>5%)in 325 Gram Samples
    E. coli 0157 Prevalence in 325 Ground Beef Portions from the Production Lot
    44
  • 45
    How Does Vaccine Help ReduceEvent Days, Hot Lots
    Cattle Prevalence
    Carcass Prevalence
    Concentration
    Event Day
  • Cut-off the First Tail and Subsequent Ones Not as Likely to Occur
    Cattle Prevalence
    Carcass Prevalence
    Concentration
    46
  • Vaccination Reduces Variation = Risk
    The overall average prevalence of O157:H7 in cattle and ground beef is low
    Occasional “event days” or “hot lots” drive the risk
    Small fraction of carcasses are highly contaminated
    Vaccination has a disproportionate impact on thesetail-end events, reducing frequency of high prevalence cattle and high concentration of bacteria
    47
  • Summary
    Analysis included impact of biological variation and uncertainty in parameters
    Modeled from “farm to fork” using best available scientific data
    Showed that vaccination reduces
    Human 0157:H7 cases
    Risk of FSIS regulatory detection
    Chance of large outbreak from a lot
    Frequency and magnitude of “event days”
    48
  • Questions
    Why Does the Industry Worry About E. coli O157:H7?
    Pre-harvest Interventions Work Sometimes,But Not Other Times
    E. coli 0157:H7 Vaccination is One of Those Times That Works
    49
  • Appendix A
    Materials & Methods
  • Materials and Methods
    Stochastic simulation model using a farm to fork approach (Excel®, @Risk®)
    Stochastic – pick numbers randomly from defined distribution
    Impact of E. coli O157:H7 vaccination in reducing the prevalence (% fecal positive cattle) and concentration (log CFU in trim) modeled
    Consists of three modules
    Production
    Slaughter
    Consumption
    51
  • Mathematical Model “Converts” 0157:H7 Shedding Cattle to Human Illnesses
    (Best Available Data)
    Production
    Slaughter
    Consumption
    52
  • What is a “Stochastic Simulation”?
    Probability of Various E. coliPrevalence Occurrences
    Exact cattle prevalence and other variables are unknown and changing
    Studies give a range and statistical distribution which is often non-normal (Poisson)
    Computer uses all those possible numbers to calculate multiple results (n=10,000)
    53
  • Slaughter Module – Individual Carcass Modeled
    54
    Stochastic Variables
  • Modeling Assumptions
    The E. coli O157:H7 prevalence in pre-evisceration beef carcasses is proportional to the fecal prevalence in the feedlot
    All beef imported (~40%) into the US is destined for mixing withdomestic ground beef
    The E. coli O157:H7 prevalence and concentration in imported ground beef is similar to that in ground beef from unvaccinated domestic steerand heifer slaughter
    The ground beef processed in this US is consumed domestically
    The number (CFU/serving or CFU/325g sample) of E. coli O157:H7 in a portion of ground beef from a production lot is Poisson distributed
    The impact of internal test-and-hold protocols is not considered
    The FSIS ground beef test data are assumed to be from a representative random sample of ground beef production lots in the US
    55
  • 56
    Production Module
    Estimates the E. coli O157:H7 Prevalence in Vaccinated and Unvaccinated Feedlots
    • Prevalence among feedlots and within feedlots estimated.
    • Vaccination reduces prevalence by fixed percent on average. Multiple different efficacy scenarios can be run
    • Variability in feedlot prevalence and impact of vaccination modeled stochastically by exponential and binomial distributions
    Production
    Slaughter
    Consumption
  • Scenarios Built Around Reductions in Prevalence and E. coli Concentration
    Additionally, Simulated for Various Levels of Product Adoption from 0% to 100%
    57
  • Slaughter Module – Carcass Prevalence
    Fecal
    Prevalence (from Production Module)
    Linear Coefficient (Elders 2000, Barkocy-Gallagher 2003 and Arthur 2007)
    Pre-evisceration Carcass Prevalence
    Effectiveness of Generic Post Slaughter Interventions (Elders et al. 2000, Arthur et al. 2004 and Barkocy Gallagher et al. 2003)
    Post Chill Carcass Prevalence
    Modeled as a Binomial Distribution
    Number Contaminated Carcasses per Production Lot
    58
  • Slaughter Module – Bacterial Concentration
    Concentration on a Pre-evisceration Carcass
    Contaminated Surface Area (8000 cm2/Carcass)
    Total CFU/Carcass at Pre-evisceration
    Effectiveness of Post Slaughter Interventions Estimated from GenericE. coli and APC Data
    Total CFU/Carcass at Post Chill
    The Amount (CFU) Added to the Production Lot from Individual Carcasses Was Summed Up. Assumed 70 Percent of Carcass Surface Area Represented in Trim
    Total CFU per Production Lot
    59
  • Slaughter Module –Individual Carcasses Modeled
    60
  • Slaughter Module
    Estimates the prevalence and concentration of E. coli O157:H7 in beef carcasses and ground beef production lots
    About 68 Simulated carcasses for a 10,000 pound production lot, depends on average carcass weight
    Variable E. coli O157:H7 concentrations on contaminated carcasses were modeled
    Production
    Slaughter
    Consumption
    61
  • Total Carcass Contamination a Function of Fecal Shedding, Amount of Bacteria and Surface Area
    62
  • Slaughter Module – Lot Types
    Production Lot from Unvaccinated Cattle
    Production Lot from “Vaccinated” Cattle
    • Includes ground beef trim from domestic and imported sources
    • E. coli O157:H7 prevalence and concentration in ground beef from domestic and imported sources assumed to be similar
    • Domestic portion of ground beef in the lot is from vaccinated cattle
    • Imported ground beef is assumed to be from unvaccinated cattle
    63
  • Consumption Module
    Estimates overall number of E. coli O157:H7 illnesses due to consumption of ground beef from steers and heifers
    Fraction of E. coli O157:H7 illnesses attributed to ground beef consumption estimated from outbreak and epidemiological studies
    Similar to the approach used Withee et al., 2009
    64
    Production
    Slaughter
    Consumption
  • Consumption Module Attribution Calculation
    65
    Domestic Cattle Slaughter and Beef Import Data
    Number of E. coli O157:H7 Contaminated Servings /Year
    FSIS Ground Beef Testing Data
    Baseline Probability of Illness per Contaminated Serving of Ground Beef
    CDC Foodnet Data
    Adjusted for Under Diagnosis
    Number of Illnesses from Ground Beef per Year
    Fraction of Illnesses Attributed to Ground Beef Consumption
  • 66
    Consumption Module
    Outputs – mean number of E. coli O157:H7 illnesses per year in the US due to consumption of ground beef from steers and heifers calculated from:
    Variables
    • Baseline probability of E. coli O157:H7 illness per contaminated serving of ground beef consumed
    • Estimated number of contaminated servings per production lot
    • Estimated number of production lots from vaccinated and unvaccinated cattle processed
  • 67
    Methods Review
    Stochastic simulation model to evaluate the impact of O157:H7 vaccination on key epidemiologicaloutcome measures
    Considered a reduction in the O157:H7 prevalence as well as concentration in cattle feces due to vaccination
    Impact of this reduction on various risk outcomes was evaluated by simulating the relationships between the O157:H7 prevalence and concentration at various points in the ground beef supply chain
    The uncertainty and variability associated with the O157:H7 contamination was explicitly modeled on a carcass-by-carcass basis
  • Methods Review
    Included the impact of post harvest interventions, stochastically
    Combined best available scientific data about the processes to produce ground beef
    Shows the impact of true biological variation on the prevalence and concentration of E coli before and after each process
    68
  • Appendix B
    Reference Slides
  • * Total does not add to 100% due to rounding.
    Source: 2009 Food & Health Survey, International food Information Council Foundation.
    70
    Consumers Firmly Place Food Safety Responsibility on the Production Chain
    Perceived Responsibility for the Safety of theU.S. Food Supply2009 (n=1064)
    Perceived Importance ofFood Safety Issues2009 (n=1064)*
    In general, who do you believe is responsible for food safety in the U.S.?Select all that apply.
    What, in your opinion, is the most important food safety issue today? Select one.
    Other 2%
    Food Allergens 2%
    Imported Foods
    Don’t Know
    Chemicals in Food
    Foodborne Illnesses from Bacteria
    More Than Half the Food Safety Concerns Expressed by ConsumersResides with Illnesses Stemming from Bacteria
  • How Concerned Are You About Foodborne Illnesses from Eating Ground Beef?
    Source: National Cattlemen’s Beef Association – Consumer Perceptions of Beef Safety – October 2010
    Source: IPSOS Public Affairs – July 2010
    71
    Bacterial Contamination is aGrowing Concern for Consumers
    • Concern about foodborne illness fromeating ground beef has increasedsignificantly since 2008
    • Bacteria in food currently is the number one rated food safety issue for consumers and has been the leading issue of concern for the past several years
    • Looking back over the past 10 years, bacterial concerns have been higher than all other issues except mad cow disease which was the issue of highest concern from 2002 until 2009
    • In 2001, 39 percent of consumers said they were extremely concerned about bacteria while a quarter (24%) said they were not concerned
    • In July 2010, 40 percent say they are extremely concerned about bacteria and only 7 percent say they are unconcerned
    Consumer Food Safety Concerns% Rating a 5 (Extremely Concerned) on a 5-Point Scale
    Q: On a Scale of One to Five with One Being No Concern and Five Being Extremely Concerned, How Concerned Are You About…
    IrradiatedFoods
    Mad CowDisease
    Chemical Additives
    Antibiotics
    GM Foods
    Bacteria
    Pesticides
    Hormones
  • Source: Pfizer, Consumer Marketing Research 2010, Data on File.
    Q: Listed below are some food safety concerns people may have expressed when buying or eating beef. Using the scale below, please tell us how concerned you are, if at all, with each of these issues when buying or eating beef.
    72
    Safety Concerns with Regard to Eating Beef
    • Beef consumers tend to be more concerned about E. coli than any other well-known beef pathogen. Just over one in four are extremely concerned with E. coli when eating and buying beef, and three in four express at least some level of concern
    Base: Total Respondents (N=1,029)
    Level of Concern Towards Issue(Base: Those Aware of Issue)
    % Aware of Issue
    Extremely Concerned
    Extremely/Very/Somewhat Concerned
  • 1 Schroeder T., Agricultural Economists, Kansas State University, in National Cattlemen’s Beef Association. A basic look at E. coli O157, 2004
    2 Kay S., editor/publisher of Cattle Buyers Weekly (www.cattlebuyersweekly.com), in National Cattlemen’s Beef Association.A basic look at E. coli O157, 2004
    73
    E. coli O157 Costs Duringthe Past 10 Years
    • Research has shown that beef-product recalls following outbreaks have a negative effect on demand for beef.For instance, boneless beef prices declined an average of 2.5% in the 5 days following one recall. From 1991 through 1999, beef recalls due to safety concerns were estimated to cost the industry as much as $1.6 billion in lost demand1
    • Producers have invested $20 million in check-off funds during the last decade in beef safety research while the top 10 beef packing companies spent $400 million on beef safety research. Packers have also incurred an estimated $250 million in increased operating costs due to changes at processing plants aimed at improving beef safety. Government and industry have spent at least $65 million since 1993 on E. coli O157 research, with the USDA Agricultural Research Service spending $49 million from 1993 to 2002 to research food safety
  • 74
    1 BeaconMR, March 2010
    Original mission: to solve a turkey salmonella problem, to improve poultry quality and food safety
    Key discoveries by WPC staff microbiologists led to numerous patents for a novel vaccine technology
    SRP® technology has great potential for multiple veterinary and human medical applications
    • Salmonella-SRP vaccine for cattle conditionally licensed in 2004
    • Approximately 5M doses used in US dairy industry annually in 2008 and 20091
  • Source: Emery, D.A. – “SRP Technology” presentation; Midwest Poultry Federation annual meeting, St. Paul, MN - March, 2002
    75
    State of Minnesota – Official Salmonella Test Results for Willmar Poultry Company Breeder Flocks
    Percent Positive Flocks
    10,000 hens per flock
    500 cloacal samples/flock
    50 flocks per year
    25,000 hens tested annually
    Implementation of Salmonella SRP® Vaccination Over aTwo-Year Period
  • 76
    E. coli O157:H7
    May 2010, USDA/FSIS announces
    “Pre-harvest Management Controls and Intervention Options for Reducing Escherichia coli O157:H7 Shedding in Cattle”
    FSIS Guidance notes:
    Establishments required to conduct hazard analysis that can occur before, during and after entry into establishment
    Fecal shedding is a hazard
    FSIS recommends slaughter establishments receive cattle that implement one or more documented pre-harvest management practices to reduce fecal shedding
  • 77
    Why Vaccines at Pre-harvest
    These product licenses are conditional. Efficacy and potency test studies are in progress
    Vaccines enable a natural ally: the animal’s immune system
    Addressing the problem pre-harvest should allow processing interventions to be more effective
    Incoming pathogen burden can overwhelm in-plant processes
  • 78
    SRP Technology
    Pathogenic Gram-negative bacteria, including E. coli O157:H7 and Salmonella, require iron to liveand replicate
    SRP vaccines target the proteins necessary to transport iron into the bacterial cell, using the animals’ immune system to block iron passage
    As a result, without iron, the bacteria die
  • P<0.0001
    Data on file, Epitopix LLC Study Report No. 0606, Pfizer Inc.
    79
    Reduced Number of Salmonella Newport Infected Animals
    Percent Positive for Salmonella Newport Infection Following Challenge
    • 75% fewer infected animals 14 days post-challenge
  • P<0.0001
    Data on file, Epitopix LLC Study Report No. 0606, Pfizer Inc.
    80
    Quantity of Salmonella Shedding in Feces: Average Colony Forming Units (CFU) per Gram
    Log 10 CFU/ g
    28 Samplings (AM/PM for 14 Days)
  • 81
    2008 Field Study: Salmonella in Cull Dairy Cows
    Guy Loneragan – WTAMU (Western Texas A&M University)
    Loneragan, GH et al. Salmonella in Cull Dairy Cattle of the Texas High Plains. 89th Annual Meeting of the Conference of Research Workers in Animal Diseases, December 7-9, 2008, Chicago, Illinois
    Enrolled 9 West Texas dairies (all >2,000 cows)
    Sampled 706 cows culled from the dairies, either on site or at regional sales barn
    Cultured for Salmonella
    Serotype, susceptibility testing, quantification
    Salmonella recovered from 32.6% of samples
    Varied by month and dairy
    Dairy burden ranged from 4.4% to 86.3%
    Within-herd burden remained relatively constant over time
  • Loneragan, GH et al. Salmonella in Cull Dairy Cattle of the Texas High Plains.  89th Annual Meeting of the Conference of Research Workers in Animal Diseases, December 7-9, 2008, Chicago, Illinois.
    Vaccine = Salmonella Newport Bacterial Extract Vaccine
    82
    Salmonella Prevalence in Cull Dairy Cows: 9 Large Texas Dairies
    Vaccine
    Vaccine
    Vaccine
  • Hermesch DR, Thomson DU, Loneragan GH, Renter DR, White BJ. Effects of a commercially available vaccine against Salmonella enterica serotype Newport on milk production, somatic cell count, and shedding of Salmonella organisms in female dairy cattle with no clinical signs of salmonellosis. AJVR 2008;69(9):1229-1234
    Vaccine = Salmonella Newport Bacterial Extract Vaccine
    83
    Effect of Vaccination on Milk Production in Sub-clinically Infected Cows
    Effect of Vaccination with Salmonella Newport Bacterial Extract Vaccineon SCCs (cells/mL)* (P=0.01)
    SCCs (cells/mL) x 1,000
    * At 30 to 60 days of lactation
  • 84
    Control of E. coli O157 with E. coli Bacterial Extract Vaccine
    Thomson DU, Loneragen GH, Thornton AB, et al., Use of a Siderophore Receptor and Porin Proteins-Based Vaccine to Control the Burden of Eschericia coli O157:H7 in Feedlot Cattle. Foodborne Pathogens and Disease 2009; Vol. 6, Number 7, 871-877
    Same technology platform as Salmonella Newport Bacterial Extract vaccine
    SRPs harvested from stx-negative E. coli O157:H7
    Study conducted in commercial feedlot
    Thomson et al. FPD. 2009;6:871-877
    Animals randomized from source pens into 20 pens of 60 to 70animals per pen
    10 pens vaccinated d0, d21, d42
    Other 10 matched pens received placebo
    Study personnel masked as to treatment allocation
    Sampled d0, d42, and d98
    Study Led by Daniel U. Thomson, K State
  • Thomson DU, Loneragen GH, Thornton AB, et al., Use of a Siderophore Receptor and Porin Proteins-Based Vaccine to Control the Burden of Eschericia coli O157:H7 in Feedlot Cattle. Foodborne Pathogens and Disease 2009; Vol. 6, Number 7, 871-877
    85
    E. coli Bacterial Extract Vaccine: Results
    E. coli 0157 Prevalence
  • Thomson DU, Loneragen GH, Thornton AB, et al., Use of a Siderophore Receptor and Porin Proteins-Based Vaccine to Control the Burden of Eschericia coli O157:H7 in Feedlot Cattle. Foodborne Pathogens and Disease 2009; Vol. 6, Number 7, 871-877
    86
    E. coli Bacterial Extract Vaccine: Results
    E. coli 0157 Prevalence
    Log10 MPN/g
  • 87
    A “Food System” Approach to Pathogen Reduction
    PreparationInterventions
    Harvest & Post-harvestInterventions
    Pfizer Animal HealthE. Coli Bacterial Extract Vaccine
    Reduction Begins at the Source….
  • Source: Emerging Options to Control E. coli O157:H7 Pre-harvest; Guy H. Loneragan, West Texas A&M University Canyon, Texas, USA; June 24-25, 2009, Angers, France
    88
    Another Hurdle Within a System
    E. coli O157
    E. coli O157
    Consumers
    Harvest
    Pre-harvest
    Currently Multiple Post-harvest Controls
    • Most of the time, within plant interventions effectively mitigate what comes in on the cattle
  • Source: Emerging Options to Control E. coli O157:H7 Pre-harvest; Guy H. Loneragan, West Texas A&M University Canyon, Texas, USA; June 24-25, 2009, Angers, France
    89
    Another Hurdle Within a System
    E. coli O157
    E. coli O157
    E. coli O157
    Consumers
    Harvest
    Pre-harvest
    Currently Multiple Post-harvest Controls
    • Sometimes, these interventions fail – E. coli O157 detected in:
    • 0.9% of trim combos;
    • 0.33% of GB (ground beef) samples
  • Source: Emerging Options to Control E. coli O157:H7 Pre-harvest; Guy H. Loneragan, West Texas A&M University Canyon, Texas, USA; June 24-25, 2009, Angers, France
    90
    Another Hurdle Within a System
    E. coli O157
    E. coli O157
    SRP
    Consumers
    Harvest
    Pre-harvest
    Currently Multiple Post-harvest Controls
    • For example, if pre-harvest prevalence reduced from x to y, what is the extent of the impact on z (rate of microbial defects)