The Role of an Food Examiner in the Control and Investigation of Food Poisoning Outbreaks John Waddell Glasgow Scientific Services.

The Role of an Food Examiner in the The Role of an Food Examiner in the Control and Investigation of Food Control and Investigation of Food

Poisoning Outbreaks Poisoning Outbreaks

John WaddellJohn Waddell

Glasgow Scientific ServicesGlasgow Scientific Services

Three main rolesThree main roles

SurveillanceSurveillance

Enforcement Enforcement

Outbreak investigationOutbreak investigation

The Queen meeting local dignitaries, June 28 1964. (Aberdeen Journal)

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“ Aberdeen in early summer 1964, was in the grip of a typhoid epidemic that was eventually to hospitalise over five hundred people. The Aberdeen outbreak highlighted the continuing potential for serious food poisoning episodes within modern food systems. It was the first such outbreak to attract intense media interest”.The Aberdeen Typhoid Outbreak, 1964

Lesley Diack and David Smith

Aberdeen 1964 – Typhoid OutbreakAberdeen 1964 – Typhoid OutbreakTraced to single 6lb Can of Traced to single 6lb Can of Argentinean Corned BeefArgentinean Corned BeefCooled in untreated river Cooled in untreated river waterwaterS.typhi thought to have S.typhi thought to have entered can through fault in entered can through fault in seamseamCross contamination from Cross contamination from meat slicer to other meat slicer to other productsproducts50 victims a day at height 50 victims a day at height of epidemic which lasted 3 of epidemic which lasted 3 monthsmonths500 hospitalised500 hospitalised

Wishaw 1996 - E.Coli 0157 Wishaw 1996 - E.Coli 0157 OutbreakOutbreak

Worst recorded case of E.coli 0157 food Worst recorded case of E.coli 0157 food poisoningpoisoning21 fatalities21 fatalitiesSource traced to apparently clean Source traced to apparently clean butcher’s shop butcher’s shop Cross contamination between raw and Cross contamination between raw and cooked meatcooked meatButchers licensing introduced as a Butchers licensing introduced as a consequenceconsequence

What did these outbreaks have in What did these outbreaks have in common?common?

Large outbreaksLarge outbreaks

Meat productsMeat products

Pathogenic organisms of faecal originPathogenic organisms of faecal origin

Causes of outbreaks hypothesised by Causes of outbreaks hypothesised by epidemiologistsepidemiologists

Inadequate HACCPInadequate HACCP

The Role of an Food Examiner in The Role of an Food Examiner in the Control and Investigation of the Control and Investigation of

Food Poisoning OutbreaksFood Poisoning Outbreaks

SurveillanceSurveillance

Enforcement Enforcement

Outbreak investigationOutbreak investigation

Food ExaminerFood Examiner

Food Safety Act 1990 places importance on role Food Safety Act 1990 places importance on role of microbiological monitoring processof microbiological monitoring process

The Food Examiner performs the statutory The Food Examiner performs the statutory function of Microbiological Examination of Foodfunction of Microbiological Examination of Food

This mirrors the Public Analysts responsibility for This mirrors the Public Analysts responsibility for Chemical Analysis of foodChemical Analysis of food

Food Safety (Sampling and Qualification) Food Safety (Sampling and Qualification) Regulations 1990 sets requirements for Regulations 1990 sets requirements for qualifications for Food Examinersqualifications for Food Examiners

Food Examiner’s ResponsibilitiesFood Examiner’s Responsibilities

Awareness of current legislation Awareness of current legislation Awareness of current methods and Awareness of current methods and standardsstandardsMethod selection and developmentMethod selection and developmentStaff trainingStaff trainingAchieve & maintain UKAS accreditationAchieve & maintain UKAS accreditation Awareness of emerging techniquesAwareness of emerging techniquesAwareness of emerging pathogensAwareness of emerging pathogens

SurveillanceSurveillance

Small local surveys ~ 20 samplesSmall local surveys ~ 20 samples

Medium sized surveys ~100 samplesMedium sized surveys ~100 samples

National surveys 1000sNational surveys 1000s

SurveillanceSurveillance

1990-Richmond Committee 1990-Richmond Committee RecommendationsRecommendations

Coordinated food surveillanceCoordinated food surveillance

Targeted food surveillanceTargeted food surveillance

More emphasis on HACCPMore emphasis on HACCP

National database to be establishedNational database to be established

Surveillance Surveillance

FSA commissioned HPS (April 2000) to FSA commissioned HPS (April 2000) to deliver UK Food surveillance systemdeliver UK Food surveillance system

Coordination of approach to surveillanceCoordination of approach to surveillance

FSS system established in 2002 by 4 FSS system established in 2002 by 4 APA Scottish labs + 4 Scottish NHSAPA Scottish labs + 4 Scottish NHS

IT and laboratory partnershipIT and laboratory partnership

FSS being rolled out across UKFSS being rolled out across UK

EnforcementEnforcement

Statutory Standards specified in Regulations Statutory Standards specified in Regulations

EC RegulationsEC Regulations

UK Regulations based on EC DirectivesUK Regulations based on EC Directives

UK RegulationsUK Regulations

Non-Statutory StandardsNon-Statutory Standards

Guidelines (e.g. HPA Guidelines for Food Guidelines (e.g. HPA Guidelines for Food Examiners)Examiners)

Industry Codes of PracticeIndustry Codes of Practice

Enforcement Enforcement

Range of Food Categories covered by EC Range of Food Categories covered by EC Microbiological Criteria RegulationsMicrobiological Criteria Regulations

Meat- carcasses, meat preparations, meat Meat- carcasses, meat preparations, meat products, MRM, minced meatproducts, MRM, minced meat

Dairy- milk, cheese, butter, cream, ice creamDairy- milk, cheese, butter, cream, ice cream

Shellfish - live and cookedShellfish - live and cooked

Fresh produce – fresh cut fruit and vegetables, Fresh produce – fresh cut fruit and vegetables, unpasteurised juice and sprouted seedsunpasteurised juice and sprouted seeds

Miscellaneous - e.g. Infant Foods, RTE foods, Miscellaneous - e.g. Infant Foods, RTE foods, Egg ProductsEgg Products

Surveillance + Enforcement = Surveillance + Enforcement = Prevention?Prevention?

SMA infant formula contaminated with SMA infant formula contaminated with Botulism sporesBotulism spores

Cadbury’s Chocolate contaminated with Cadbury’s Chocolate contaminated with Salmonella – Withdrawal of 1 Million barsSalmonella – Withdrawal of 1 Million bars

Cadbury’s lab found to have been using Cadbury’s lab found to have been using methods which underestimated the risk of methods which underestimated the risk of Salmonella contaminationSalmonella contamination

Current Rates for Food Current Rates for Food Poisoning Cases in ScotlandPoisoning Cases in Scotland

E.coli 0157 (~200 cases per annum)E.coli 0157 (~200 cases per annum)

Salmonella (~800 cases per annumSalmonella (~800 cases per annum

Campylobacter (~5000 cases per Campylobacter (~5000 cases per annum)annum)

What is an Outbreak?What is an Outbreak?

Two or more linked casesTwo or more linked cases

A greater than expected rate of illness or A greater than expected rate of illness or infection in the communityinfection in the community

A single case of certain serious, possibly A single case of certain serious, possibly contagious infections suggesting that there contagious infections suggesting that there will be many more in the community will be many more in the community

Outbreak Control TeamOutbreak Control Team

OCT are chaired by a CPHMOCT are chaired by a CPHM

Format and agenda in accordance with Format and agenda in accordance with Outbreak Control PlanOutbreak Control Plan

Purpose is to identify whether there is an Purpose is to identify whether there is an outbreakoutbreak

Identify the sourceIdentify the source

Identify the casesIdentify the cases

Stop the outbreakStop the outbreak

Learn from the outbreakLearn from the outbreak

Outbreak Control Team MembersOutbreak Control Team Members

CPHM(s)CPHM(s)Infection Control Specialist(s)Infection Control Specialist(s)EHO(s)EHO(s)Clinician(s)Clinician(s)Medical Microbiologist(s)Medical Microbiologist(s)

++Food Examiner(s)Food Examiner(s)

+ + Water AuthoritiesWater AuthoritiesOther agencies – Police, Public Relations etcOther agencies – Police, Public Relations etc

Targeted examinationTargeted examination

Based on clinical symptomsBased on clinical symptoms

Based on epidemiologyBased on epidemiology

Based on availability of sampleBased on availability of sample

Standard Microbiological Technique for Standard Microbiological Technique for Detection of PathogensDetection of Pathogens

1.1. Pre-enrichment – To boost the numbers Pre-enrichment – To boost the numbers of organisms to detectable levelsof organisms to detectable levels

2.2. Selective enrichment – To further boost Selective enrichment – To further boost the numbers of the target organism the numbers of the target organism whilst reducing levels of otherswhilst reducing levels of others

3.3. Selective isolationSelective isolation

4.4. PurificationPurification

5.5. ConfirmationConfirmation

Some pathogens can present new Some pathogens can present new challengeschallenges

E.coli 0157 – very low E.coli 0157 – very low infectious doseinfectious dose

Technique developed Technique developed using using Immunomagnetic Immunomagnetic Beads as an aid to Beads as an aid to isolationisolation

Principle of IMSPrinciple of IMS

-IMS + low volumes of sample low sensitivity of detection(e.g. 20 cfu/ml in PBS)

Campylobacter Campylobacter

Campylobacter – Campylobacter – Growth is Growth is microaerophilicmicroaerophilic

Requires incubation Requires incubation in modified in modified atmosphereatmosphere

+ complex nutritional + complex nutritional requirementsrequirements

The Role of an APA Food Examiner in the The Role of an APA Food Examiner in the Control and Investigation of Food Poisoning Control and Investigation of Food Poisoning

OutbreaksOutbreaks

SUMMARYSUMMARY

SurveillanceSurveillance

EnforcmentEnforcment

Outbreak InvestigationOutbreak Investigation

Pathogens that emerged in late 20Pathogens that emerged in late 20thth Century Century

Listeria monocytogenesListeria monocytogenesYersinia enterolyticaYersinia enterolyticaE.coli 0157E.coli 0157Campylobacter jejuniCampylobacter jejuniBSEBSECryptosporidiumCryptosporidiumHelicobacter pylori Helicobacter pylori HIVHIVSARSSARSAvian FluAvian FluClostridium difficileClostridium difficileLegionella pneumophilaLegionella pneumophilaEnterobacter sakazakkiEnterobacter sakazakkiMRSAMRSA

Thank you for listeningThank you for listening

Any Questions?Any Questions?