gajadhar - trichinella vf rome workshop 29may08 [modalità

A Comprehensive On-site Diagnostic Program for the

Detection of TrichinellaAlvin A. Gajadhar

Centre for Food-borne and Animal ParasitologyCanadian Food Inspection Agency

Saskatoon, SK. Canada

Reference LaboratoryReference Laboratory-- TrichinellosisTrichinellosisCollaborating Centre for FoodCollaborating Centre for Food--borne Zoonotic Parasitesborne Zoonotic Parasites

Purpose for Testing

• Surveillance

- for control management

- for status declaration

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- for status declaration

• Food safety

• Export requirement

• Import verification

• Disease outbreak investigation

Testing Locations

I. Off-site (samples collected elsewhere)

- most diagnostic labs

- reference labs

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- reference labs

II. On-site (samples collected on premises)

- abattoirs/packing plants

- field labs

Oversight of Testing Laboratories

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National Reference andDiagnostic Laboratory

Diagnostic Laboratories(Off-Site)


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Diagnostic Laboratories(On-Site)


Reference and Diagnostic Laboratory(International)

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National Reference andDiagnostic Laboratories


Diagnostic Laboratories(On-Site)

Requirements for off-site and on-site testing are similar

• QA system and manual• Purpose of laboratory• Purpose of testing • Appropriate test method (fit for purpose)

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• Appropriate test method (fit for purpose)• Standardized and validated method• Trained and competent analysts• Suitable facilities• Proficiency testing• External audits for lab accreditation/certification

Key Elements of On-site QA Program

• Quality Goals – measurable• Defined Test Method - suitable, reliable• Samples - suitable, stable• Internal Quality Control - CCP

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• Internal Quality Control - CCP• External Quality Procedures - PT, accreditation• Record keeping - sample tracking and traceback• Documented results • Procedures (SOP’s) and Documentation • QA Manual

All Tests are Not Equal

• Non-validated tests

• Validated tests (a validation continuum)

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Validated Test Method

• Based on documented evidence that the method does what it is intended to do

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• The robustness, repeatability, and reproducibility of the method under certain conditions have been evaluated and documented

• An important element of quality control and provides an assurance of reliability

All Tests are Not Equal

• Non-validated tests

• Validated tests (a validation continuum)

• Harmonized tests

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• Harmonized tests

• Equivalent tests

• Prescribed tests

• Alternative tests

• Ad-hoc tests

An Experience

• Six persons with food poisoning in city hospitalized • All suspect food confiscated for testing• Wild boar meat tested for Trichinella at local lab• Meat released to owners for consumption

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• Meat released to owners for consumption• Number of cases increased to 24• Cooked sausage and roast submitted to reference lab• Method available was not fit for purpose, but …• Roast: no larvae recovered• Sausage: motile larvae recovered• > 40 cases of confirmed trichinellosis

QA Manual is a Documented Plan to Meet Management and Technical Goals

• Reproducibility and reliability of results• Permanent record of sample handling• Identification and elimination of errors due to poor

performance of media, reagents, equipment, etc.

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• Identification and elimination of errors due to poor performance of media, reagents, equipment, etc.

• Permanent record of equipment performance• Equipment maintenance and calibration procedures• Test procedures and results• Analyst training and competence• Problem solving and corrective action

A National Program for Trichinella Testing of Pork and Horsemeat

by On-site Industry Laboratories

- Developed and implemented by CFAP

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- In operation for 11 years, since 1997

- 14 laboratories accredited, 90 analysts trained and certified

Background

• CFIA Centre for Food-borne and Animal Parasitology (CFAP) accredited for diagnostic testing as per ISO/IEC Standard 17025

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17025 Gajadhar and Forbes. 2002. An internationally recognized quality assurance system for diagnostic parasitology in animal health and food safety, with example data on trichinellosis. Vet. Parasitol. 103, 133-140.

• based on this standard, a national program was developed to accredit industry on-site laboratoriesForbes, Scandrett, and Gajadhar. 2005. A program to accredit laboratories for reliable testing of pork and horsemeat for Trichinella. Vet. Parasitol. 132, 173-177.

Accreditation for On-site Testing

• provides testing capacity to meet export demands

• meets internationally acceptable QA standards

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• meets internationally acceptable QA standards

• provides documentation of compliance with acceptable testing standards

• Accreditation and oversight provided by a national reference laboratory


Reference and Diagnostic Laboratory(International)

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Diagnostic Laboratory(Off-Site)

Diagnostic Laboratory(On-Site)

Main Criteria for Accreditation

1. Defined Quality Assurance System2. Suitable Laboratory Facilities3. Standardized and Validated Method 4. Certified Analysts

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4. Certified Analysts5. External Audit

Consistent with ICT Recommendations Appendix 2. Quality assurance program for Trichinella testing

CFAP provides information package on the accreditation process to interested parties

An Accreditation Process for On-site TestingSubmission of application and payment of fees

Review of application

Report of required corrective items to candidate

Completion of corrective items

Preparation of Quality Manual (QM)

Review of completed QM

Report of required corrective actions (QM) to candidate

Completion of corrective actions

Preparation of laboratory facilities

Acquisition of all required test supplies and equipment

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Acquisition of all required test supplies and equipment

On-site audit (scheduling required)

Report of required corrective actions to candidate


Preparation of proficiency samples (scheduling required)

Training of analysts at CFIA Reference Laboratory (scheduling required)

Successful proficiency testing on-site (scheduling required)

Comprehensive on-site audit (scheduling required)

Report of required corrective actions to candidate


Recommendation of certification

Certification letter issued by CFIA to candidate

Candidate arranges with CFIA Vet-in-Charge for export certification

Quality Assurance Manual

• It is a statement of the laboratory’s policies and good laboratory management practices

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• Describes the quality assurance system used in a testing laboratory

• Documents plans to meet management and technical goals of the quality assurance system

Contents of a QA Manual

• Who (titles and responsibilities)

• What (scope and activities)

• When (frequency)

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• When (frequency)

• Where (location)

• How (methodology and mechanisms)

• Why (purpose)

Example Quality Assurance Manual1. Table of Contents2. Laboratory Information3. Test Methods and Procedures4. Equipment and Supplies5. Quality Control Activities6. Sample Handling7. Record Keeping Procedures

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7. Record Keeping Procedures8. Staff Training9. Proficiency Testing Program10. Problem Solving and Corrective Actions11. Mechanism for Handling Complaints12. Proprietary Rights and Confidential Information13. Sub-contracting14. References15. Appendices

Suitable Laboratory Facilities

• Controlled, clean environment for testing

• Equipment and consumable supplies must meet required specifications of the test method

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method

• Must comply with local safety regulations

Standardized/ValidatedMethod

• Magnetic stirrer method for pooled sample digestionEU Directive EC No 20705/2005

• Double separatory funnel procedure for pooled sample digestion

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sample digestionGajadhar, Forbes, and Rajic, 1996

• Digestion assay more sensitive than trichinoscopyForbes, Parker and Scandrett. 2003. Comparison in pork. J Food Prot 66, 1043-1046

• Validation of double separatory methodForbes and Gajadhar. 1999. A validated Trichinelladigestion assay and an associated sampling and quality assurance system for use in testing pork and horse meat. J Food Prot 62, 1308-1313

Analyst Certification

• 5-day training course conducted at CFAP

• training manual provided

• Candidates must pass a practical

Certificate of Training

John Smith

has successfully completed a training course on the Centre for Animal Parasitology’s Double Separatory Funnel Procedure for the Detection of Trichinella Larvae in Walrus Meat (Version 2.0, June 2003). This course was held at the Centre for Animal Parasitology,

Saskatoon Laboratory, Canadian Food Inspection Agency.

__________________________ __________________________ __________________________ __________________

Dr. A. Gajadhar Dr. L Forbes Dr. B. Scandrett Date of Issue Section Head Accreditation Coordinator Accreditation ManagerCentre for Animal Parasitology Trichinella Test Program Trichinella Test Program

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• Candidates must pass a practical examination at CFAP and at on-site laboratory

• A total of 90 analysts comprising 14 different laboratories have been certified since 1997

External Audit

• Initial on-site audit conducted by CFAP to verify key criteria are met

• Major and minor non-conformances must

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• Major and minor non-conformances must be addressed within specified time frame before accreditation is recommended

• Biannual audits conducted thereafter

Proficiency Testing

• Proficiency panels performed 2-4 times per yr

• Required to ensure competence of analysts and quality system of testing

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and quality system of testing

• Prepared from experimentally infected rats Forbes, Rajic, and Gajadhar. 1998. Proficiency samples for quality assurance in Trichinella digestion tests. J Food Prot 61, 1396-1399

Vallée, Macé, Forbes, Scandrett, Durand, Gajadhar, Boireau. 2007. Use of Proficiency Samples To Assess Diagnostic Laboratories in France Performing a Trichinella Digestion Assay. J Food Prot 70, 1685-1690(6)

Proficiency Testing (cont’d)

• Encapsulated larvae recovered from semi-digested infected meat

• Meat-balls prepared from ground-beef

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• Meat-balls prepared from ground-beef• Three levels of larval loads in panels (L,M,H)• Proficiency panels validated prior to

distribution• Proficiency testing conducted according to

pre-established guidelines

Proficiency Testing Results

• Evaluation of system and analysts• Interpretation according to purpose for testing• Positive/negative versus quantitative• Goal of ≥ 75% larval recovery from each

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• Goal of ≥ 75% larval recovery from each proficiency sample

• Food safety goal of < 1 LPG of meat• Corrective actions may be required• Need for establishing reasonable and achievable

guidelines

Questions/Comments?

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Questions/Comments?