Comprehensive Report on the 2004 Outbreak of High Pathogenicity Avian Influenza (H7N3) in the Fraser Valley of British Columbia, Canada.

June 30, 2004
minor revisions November 24, 2004

Canadian Food Inspection Agency

Editor: Dr Wayne Lees, Animal Disease Surveillance Unit, CFIA

Assistant editor: Lawana Chown, Animal Health and Production Division, CFIA

Contributors

Many people have contributed to this document and their efforts are gratefully acknowledged below.

Dr Wayne Lees, Editor

Lawana Chown, Assistant editor

Anderchek, Dr Denis - CFIA
Andreas, Kae - CFIA
Argue, Dr Connie - CFIA
Bouchard, John - CFIA
Bowes, Dr Victoria - BCMAFF
Byrne, Dr Sean - BCMAFF
Caya, Dr Francois - CFIA
Clarkson, Bruce - CFIA
Geale, Dr Dorothy - formerly with CFIA
Gray, George - Poultry industry
Hahn, Dr John - APHIS/USDA
Hayes, Dr Doug - CFIA
Hopkins, Dr Ralph - CFIA
Inch, Dr Carolyn - CFIA
James, Dr Cheryl - CFIA
Kiley, Dr Cornelius - CFIA
Kingsbury, Linda - HC
Knight, Ray - CFIA
Lafortune, Dr Pierre - CFIA
Leighton, Dr Ted - CCWHC
Levesque, Dr Gaetan - CFIA
Martin, Dr Michael - CFIA
McClendon, Dr Jim - CFIA
McGeoghegan, Dr Margaret - CFIA
Myers, Lawrna - CFIA
Nicholson, Ruth - HC
Owen, Dr Phil - CFIA
Pasick, Dr John - NCFAD/CFIA
Patch, Scott - PEP, Government of BC
Paulson, Stewart - BCMAFF
Power, Dr Christine - CFIA
Robinson, Dr John - BCMAFF
Schwartz, Dr Dan - CFIA
Scott, Dr Kathy - CFIA
Skowronski, Dr Danuta - BCCDC
Stephens, Dr Sandra - CFIA
Stepushyn, Dr Ken - AHPD/CFIA
Tam, Dr Theresa - HC
Tweed, Aleina - BCCDC
Wince, Dr Witold - CFIA
Wu, Dr Tong - CFIA
Zosiuk, Gord - CFIA

TABLE OF CONTENTS

• EXECUTIVE SUMMARY
• 1. INTRODUCTION
  • 1.1 Background on avian influenza
    • 1.1.1 Definition
    • 1.1.2 History
    • 1.1.3 Etiology
    • 1.1.4 Worldwide distribution
    • 1.1.5 Agent survival
    • 1.1.6 Pathogenesis
    • 1.1.7 Clinical manifestations
      • 1.1.7.1 Incubation period - mortality/morbidity
      • 1.1.7.2 Clinical signs and lesions
    • 1.1.8 Prognosis
  • 1.2 Historical information on avian influenza in Canada
    • 1.2.1 Surveillance in domestic poultry
    • 1.2.2 Wild bird surveillance
  • 1.3 Structure of the poultry industry in Canada
  • 1.4 Structure of the poultry industry in the Fraser Valley of British Columbia
    • 1.4.1 Chicken meat industry
    • 1.4.2 Commercial egg laying industry
    • 1.4.3 Broiler hatching egg industry
    • 1.4.4 Turkey meat industry
    • 1.4.5 Layer breeders and turkey breeders
    • 1.4.6 Other poultry species
    • 1.4.7 Feed mills
    • 1.4.8 Hatcheries
    • 1.4.9 Poultry slaughter and processing plants
    • 1.4.10 Poultry handling
    • 1.4.11 Egg grading and processing stations
    • 1.4.12 Poultry industry wastes
  • 1.5 Import/export trade data
    • 1.5.1 Poultry imports into Canada
    • 1.5.2 Poultry and egg exports out of Canada
    • 1.5.3 British Columbia's interprovincial trade in poultry and poultry products
• 2. THE VETERINARY INFRASTRUCTURE IN CANADA
  • 2.1 The federal veterinary infrastructure
    • 2.1.1 Material (including financial) resources
    • 2.1.2 Human resources
    • 2.1.3 Laboratory services
    • 2.1.4 Legislative authority
      • 2.1.4.1 Health of Animals Act
      • 2.1.4.2 Health of Animals Regulations
      • 2.1.4.3 Reportable Diseases Regulations
      • 2.1.4.4 Compensation for Destroyed Animals Regulations
      • 2.1.4.5 Meat Inspection Act and Regulations
      • 2.1.4.6 Feeds Act and Regulations
      • 2.1.4.7 Agriculture and Agri-Food Administrative Monetary Penalties Act and Regulations
  • 2.2 Provincial veterinary infrastructure
    • 2.2.1 Provincial veterinary services
    • 2.2.2 Veterinary colleges
  • 2.3 The private veterinary infrastructure
• 3. INFRASTRUCTURE IN PLACE DURING THE OUTBREAK
  • 3.1 The role of CFIA during the outbreak
    • 3.1.1 CFIA's Foreign Animal Disease Plans
    • 3.1.2 Emergency Operations Centres established
      • 3.1.2.1 British Columbia EOC
      • 3.1.2.2 National EOC
    • 3.1.3 Communications during the outbreak
  • 3.2 The role of provincial and municipal authorities during the outbreak
  • 3.3 The role of private poultry and swine veterinarians during the outbreak
  • 3.4 The role of poultry producer organizations during the outbreak
  • 3.5 Cooperation with USDA; other international visitors
  • 3.6 The role of human health authorities during the outbreak
    • 3.6.1 Human health agencies involved
    • 3.6.2 Occupational health and safety
    • 3.6.3 Human surveillance
    • 3.6.4 Employee Assistance Program
• 4. DESCRIPTION OF THE OUTBREAK
  • 4.1 Infected premises 1
  • 4.2 Infected premises 2
  • 4.3 Progression of the outbreak during March
  • 4.4 Progression of the outbreak during April-May
  • 4.5 Conclusion of the outbreak in June
  • 4.6 Chronology of the outbreak
• 5. DISEASE CONTROL ACTIONS TAKEN
  • 5.1 Working hypothesis on transmission of the disease
  • 5.2 Surveillance
    • 5.2.1 Tracing forward and backward at the outset of the outbreak
    • 5.2.2 Subsequent traceout investigations
    • 5.2.3 Surveillance overview
    • 5.2.4 Surveillance protocols
      • 5.2.4.1 Dead bird surveillance
      • 5.2.4.2 Enhanced flock surveillance program (live bird testing and flock health questionnaires)
      • 5.2.4.3 Pre-slaughter surveillance
      • 5.2.4.4 Pre-emptive depopulation surveillance
      • 5.2.4.5 Backyard flock surveillance
      • 5.2.4.6 Sick bird calls
  • 5.3 Movement restrictions
  • 5.4 Destruction of infected commercial flocks
  • 5.5 Destruction of infected backyard flocks
  • 5.6 Exemptions to depopulation
  • 5.7 Disposal activities
    • 5.7.1 Disposal of infected birds and products
    • 5.7.2 Disposal of non-infected birds and products
  • 5.8 Cleaning and disinfection of facilities and equipment
  • 5.9 Compensation
  • 5.10 Enforcement issues
  • 5.11 Lifting of restrictions
• 6. DIAGNOSTIC FINDINGS
  • 6.1 Clinical signs
  • 6.2 Pathology findings
  • 6.3 Diagnostic findings by NCFAD
• 7. FOLLOW-UP TO THE OUTBREAK
  • 7.1 Case-control study
  • 7.2 Aerosol sampling project
  • 7.3 Environmental spread model
  • 7.4 Evaluation of disposal methods
  • 7.5 Information system linkages
    • 7.5.1 GIS and MS Access database
    • 7.5.2 Laboratory information tracking system
    • 7.5.3 Foreign animal disease outbreak information system
• 8. CONCLUSION
• 9. REFERENCES
• 10. RECENT LITERATURE ON AVIAN INFLUENZA

11. APPENDICES

• Appendix 1 - The role of wild birds as a source of LPAI (H7N3)
• Appendix 2 - Cleaning and disinfection protocol for poultry related vehicles leaving the avian influenza control area to the United States
• Appendix 3 - Interim case/Infection definitions for human H7 avian influenza infections
• Appendix 4 - Table of avian influenza infected premises
• Appendix 5 - Positive premises with 1 & 3 km zones
• Appendix 6 - Progression of the outbreak at key dates - showing infected farms
• Appendix 7 - Epidemic curve of the outbreak in commercial flocks
• Appendix 8 - Revised high risk region
• Appendix 9 - Detailed chronology of events
• Appendix 10 - Genetic relatedness of recent avian influenza isolates
• Appendix 11 - The hatchery as a potential source of AI transmission in British Columbia
• Appendix 12 - CFIA extended producer questionnaire
• Appendix 13 - Determining high risk contacts of infected premises
• Appendix 14 - Timeline of contacts prior to a positive diagnosis
• Appendix 15 - Dead bird surveillance
• Appendix 16 - Protocol for avian influenza positive premises
• Appendix 17 - A profile of the BC poultry industry

TABLES AND FIGURES

Next page: Executive Summary