Recurring hepatitis A outbreaks in the EU/EEA: food tracing activities

12 November 2015

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Terms of Reference

MANDATE M-2013-0315

Therefore, in line with the general request for scientific and technical assistance as mentioned above, and I particular as indicated in ToR 3, I would like to ask EFSA for assistance in the ongoing investigations.Under the coordination of Unit G4: Food, Alert System and Training, the tracing back & forward exercises of the affected Member States should be merged and analysed to identify the potential links and also data gaps. Moreover, advice on the common source of the outbreak should be given and guidance on the robustness of evidence pointing towards suspected sources based on epidemiological links and laboratory analysis (including molecular testing) should be given Ares (2013)3322396 of 23rd October 2013

Recurring hepatitis A outbreaks in the EU/EEA: food tracing activities

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WORKFLOW IN OUTBREAK INVESTIGATIONS

Status

• Collection of existing evidence• Starting point for tracing (food & time)

Tracing

• Mapping of food pathways through EU• Identification of Hot Spots

Analysis

• Collection of additional evidence• Interpretation and conclusions

Recurring hepatitis A outbreaks in the EU/EEA: food tracing activities

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DATA ANALYSIS: BUILDING THE FOOD SUPPLY CHAIN

SupplierEstablishmentCustomerProduct Ingredient

SupplierEstablishmentCustomerProduct Ingredient

Identification of common links by Costumer=EstablishmentA / EstablishmentB=Supplier / Product=IngredientVerification (proof of consistency) by correct date of delivery / correct amount of the product

Recurring hepatitis A outbreaks in the EU/EEA: food tracing activities

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STARTING POINTS FOR TRACINGLevel of evidence

Lot Consumption Case 

No starting points

11.13 04.14Very high

(1)Confirmed lot (HAV 1A, OS detected)

IT: 1 lot

NO: 1 lot

Very high (2A)

Confirmed lot (HAV detected)

Consumed by at least one confirmed case

Confirmed case (HAV 1A, OS detected)

IT: 5 lots

FR: 1(+1) lot

High (2B) Suspected lot Consumed by at least one confirmed case

Confirmed case (HAV 1A, OS detected)

IT: 5 lots

NO: 1 lot

High (2C) Confirmed lot (HAV detected)

IT: 8 lots

Medium (3A) Possible lot

Produced in reasonable time before infection of at least one confirmed case

Confirmed case (HAV 1A, OS detected)

IE: 11 cases

SE: 2 cases

NL: 8 cases

Low (3B) Suspected lot Consumed by at least one non-genotyped case Probable case Not

tracedNot traced

Low (4) Possible lotProduced in reasonable time before infection of a tested case

Probable case Not traced

Not traced

Total 43 lots or cases

Recurring hepatitis A outbreaks in the EU/EEA: food tracing activities

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IRASFFRecurring hepatitis A outbreaks in the EU/EEA: food tracing activities

The final dataset comprised 6227 transactions among 1974 food operators

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NETWORK ANALYSISRecurring hepatitis A outbreaks in the EU/EEA: food tracing activities

Principle of network graphs: the circles are the nodes (e.g. companies trading a product), the lines are the edges (e.g. representing the movement from one company to another)

Primary production

Processing

Distribution

Final preparation

Contamination

BfR Food chain lab• collects data in the right structure / performs data

validation• filters and visualizes food supply networks• performs data analysis: Scoring, cross-contamination,

regional analysis

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BULGARIAN BLACKBERRIESRecurring hepatitis A outbreaks in the EU/EEA: food tracing activities

Network visualisation of connections between all blackberry suppliers in Bulgaria (blue node) and starting points (lots, cases) in the complete dataset (excluding the Netherlands)

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DETAILED ANALYSIS – FREEZING PROCESSOR

A detailed analysis reconstructs the flow of material, incl. processing and possible cross-contamination

Recurring hepatitis A outbreaks in the EU/EEA: food tracing activities

6/11/2012 Frozen mixed berries (4800kg)

Berry Yoghurt

Jan-Mar 2011

Apr-Jun 2011

Jul-Sep 2011

Oct-Dec 2011

Jan-Mar 2012

Apr-Jun 2012

Jul-Sep 2012

Oct-Dec 2012

Jan-Mar 2013

Apr-Jun 2013

Jul-Sep 2013

Oct-Dec 2013

Jan-Mar 2014

Apr-Jun 2014

Onset dates

26/6/2012 Fresh redcurrants PL Trader (PL#404) & Producer (PL#825)

27/6/2012 Fresh redcurrants PL Trader (PL#435)

30/6/2012 Fresh redcurrants PL Trader (PL#826) & Producer (PL#1173)

1/7/2012 Fresh redcurrants PL Trader (435)

2/7/2012 Fresh redcurrants PL Trader (PL#1075) & Producers (PL#875,PL#403,PL#1185)

4/7/2012 Fresh redcurrants PL Trader (PL#1075)

10/7/2012 Fresh redcurrants PL Trader (PL#833)

15/10/2012 Frozen blackberry BG Supplier (BG#1807, BG#1884)

3/7/2012 Fresh redcurrants PL Traders (826,1038, 435,850,427) & Producers (875,403,1082,844)

18/12/2012 Frozen blackberry BG Supplier (BG#1807, BG#1884)

7/1/2013 Red berry mix (1040kg)

Smoothie of Red Berry Mix

30/1/2013 Mixed berries IQF (3150kg)

9/7/2013 Pastry

7/3/2013 Frozen mixed berries (7200kg)

Cake (Lot FR#1)

Case IE#431742

Case IE#434360

Case IE#439499

Case IE#439125

Case IE#440889

Case FR#1

Case FR#2

Case FR#3

Jan-Mar 2011

Apr-Jun 2011

Jul-Sep 2011

Oct-Dec 2011

Jan-Mar 2012

Apr-Jun 2012

Jul-Sep 2012

Oct-Dec 2012

Jan-Mar 2013

Apr-Jun 2013

Jul-Sep 2013

Oct-Dec 2013

Jan-Mar 2014

Apr-Jun 2014

FREEZING PROCESSOR

PL#273

Case IE#438998

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TWO HYPOTHESIS FOR THE OUTBREAKRedcurrants produced in Poland Blackberries from Bulgaria

31 of 35 lots/cases could be connected,additional links via cross-contamination

25 of 35 lots/cases could be connected

Connects: IT, IE, FR / NO / SE Connects: IT, IE, FR / NO / SE Nearly complete back tracing In most cases is tracing incompleteSingle point source (e.g. common primary producer) is unlikely

No common source in the chain before Bulgaria identified

Three consecutive harvest years:2011-2013

Local picking in public forest area

Main producer of redcurrants in EU Highest reported incidence of HAV in 2011 and 2012 (decrease in 2013)

Recurring hepatitis A outbreaks in the EU/EEA: food tracing activities

HAV contamination could have occurred at the freezing processor or in primary production of berries

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“Identify and assess the relevant default tracing parameters needed for tracing back & forward foodstuffs from farm to fork.

Evaluate the applicability of such datasets for the most relevant foodborne pathogens for the purpose of outbreak investigations and extend where necessary to parameters on primary production level, transport or processing steps.

Identify and recommend available IT-tools to analyse and visualize such datasets in view of determining the most probable source of contamination and data gaps.”

(Ares(2014)4315795 of 22nd December 2014, EFSA M-2015-0001)

Terms of ReferenceEC mandate on revision of the data structuresNEXT STEPS: DEMOS

Recurring hepatitis A outbreaks in the EU/EEA: food tracing activities

12... and all co-workers in EFSA and the member states.

PROJECT GROUPExpertise Epidemiologists Exposure AnalystsInvestigationsin Italy Caterina RIZZO (ISS) Gaia SCAVIA, Martina ESCHER (ISS)

in Ireland Lelia THORNTON (HSE) Lisa O'CONNOR (FSAI)in the Netherlands Barbara SCHIMMER (RIVM) Judith LEBLANC , Ingeborg BOXMAN

(NVWA)in France Elisabeth COUTURIER (INVS) Aurelié KUAKAVI (DGCCRF)in Norway Line VOLD, B Guzman (FHI) Laila JENSVOLL (NO FSA)in Sweden Lena SUNDQVIST Mats LINDBLAD (SLV)in Poland Anna BAUMANN-POPCZYK (PZH) Maciej KAŁUŻA (GIS)

European background information / MethodologyExternal Ettore SEVERI ,

Johanna TAKKINEN (ECDC)Annemarie KAESBOHRER , Christian THÖNS, Matthias FILTER (BfR), Armin WEISER

Internal (EFSA) Jane RICHARDSON (AMU) Olaf MOSBACH-SCHULZ (AMU)DG Sanco Klaus KOSTENZER (G4), Jan BAELE

(RASFF)

Recurring hepatitis A outbreaks in the EU/EEA: food tracing activities

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Q&A: WHAT NEEDS TO CHANGERecurring hepatitis A outbreaks in the EU/EEA: food tracing activities

Good Agricultural Practice (GAP). It is recommended to focus on preventive measures to avoid viral contamination rather than trying to remove/inactivate these viruses from food.

Good Hygiene Practice (GHP). Workers (including migrant pickers) in the frozen berry production chain should receive hygiene training with a focus on hand hygiene and personal cleanliness.

HAV vaccination is recommended for all non-immune berry pickers and handlers

Actors: Freezing processors, local inspectors, auditors (local and FVO), occupational safety and health, GlobalG.A.P

Training: Environmental and Occupational Health