AVIAN INFLUENZA An Animal Health Perspective Dr Thomas

AVIAN INFLUENZA An Animal Health Perspective Dr. Thomas J. Holt State Veterinarian/Director FDACS, Division of Animal Industry

Etiology • Orthomyxoviridae • Envelope • Glycoprotein projections/surface antigens • Hemagglutinin (HA) and neuraminidase (NA) • 15 hemagglutinin and 9 neuraminidase antigens • A Type designation (A - only, B or C only present in humans) • Primary reservoir is wild birds, especially water fowl • H 5, H 7 strains of primary concern 2

Avian Influenza • • • Incubation Period 3 -14 days Highly contagious (100%) Low-Path - low mortality, recover in 3 weeks • High-Path - >95% mortality within 24 hours 3

Disease in Poultry • Low pathogenic strains – mild to severe respiratory symptoms – egg production may drop by up to 45% and take 2— 4 weeks to recover • High pathogenic strains – severe respiratory distress, diarrhea, nervous signs – watery eyes and sinuses – cyanosis of the combs, wattle and shanks – swelling of the head 4

Gross Lesions Swollen head, edema Paint brush hemorrhage Excess mucous, hemorrhage 5

Why Control Low-Path H 5/H 7 AI? • Significant carcass condemnations • Significant egg production losses • Inter-state and international trade embargoes • Mutation to High Path • Potential Zoonotic Disease 6

Infection and Depopulation Spatial Patterns March 12 through June 24, 2002 7

Virginia: All Turkey and Chicken Flocks As of April 18, 2002 Turkey or Chicken Flock 8

2002 VA AI Outbreak H 7 N 2 March 7 -12 Index Case Confirmation Voluntary Company Depopulation On-Site Burial March 28 20 Positive Flocks State/Company Control Measures Controlled Slaughter Permitted 9

2002 VA AI Outbreak H 7 N 2 April 12 60 Positives Flocks 30 Flocks Pending Depopulation 24 hr. State Destruction Orders USDA Assistance Requested April 14 Initial Deployment of Task Force April 18 Full Assistance of Task Force 10

Virginia: Infected Flocks (89) As of April 18, 2002 11

2002 VA AI Outbreak H 7 N 2 April 25 Barrel or Dead Bird Surveillance 12 Flocks Positive In Initial Round May 8 West Virginia Flock Positive Intensive Surveillance No Additional Cases July 2 Last Positive Case Found to Date Continue Enhanced Surveillance 12

2002 VA AI Outbreak 197 Positive Farms/ 1000 Farms 20% 4. 7 million birds/ 56 million birds 8. 4%

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Types of farms affected No. of farms affected ……………. . . ………. 197 Turkeys (78%): Turkey breeders …………………… 28 Commercial turkeys (meat) ………… 125 Chickens (22%): Broilers (chickens) ……………. . . 13 Broiler breeders (chickens) …………. . 29 Layers (chickens) …………………. …… 2 No positives found in area backyard flocks or wild waterfowl. 16

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Incident Command Post 19

VIRGINIA AVIAN INFLUENZA TASK FORCE Personnel 20

Virginia AI Task Force Mission: To control low path AI 1. Identify and eliminate foci of infection 2. Prevent spread of disease Priorities: 1. Safety of Incident Personnel and Involved Public 2. Adherence of Strict Biosecurity Measures by Incident Personnel 21

Three Focus Areas • Surveillance • Eliminate foci of infection • Biosecurity 22

Laboratory Diagnosis • • Viral isolation AGID ELISA Battery of specific antigens to identify its serologic identity (HA and NA type). • Sera from infected chickens usually yield positive antibody tests as early as 3 or 4 days after first signs of disease. • Real time reverse transcriptase polymerase chain reaction (r. T-RT-PCR) 23

Avian Influenza Tests Virus Level AGID Directigen RT-PCR Virus Isolation 0 7 14 21 Days Post-Infection (Flock) 28 24

AI Surveillance Pre-Outbreak Breeders or Layers NPIP required Ab testing Ab At Slaughter Breeder Replacements NPIP required Ab testing Turkey Growout Broilers Ab At Slaughter None During Outbreak Weekly Ag Bi-weekly Ab Pre-Slaughter Ag/Ab Weekly Ag Pre-movement Ag/Ab Weekly Ag Pre-Slaughter Ag Post-Outbreak Ab every 4 -6 weeks Pre-Slaughter Ag/Ab Monthly Ab Pre-movement Ag/Ab Pre-Slaughter Ag/Ab Ab/Ag At Slaughter 25

Barrel Surveillance 26

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Elimination of Foci of Infection • Rapid humane euthanasia of infected flocks • Rapid removal of carcasses • Disposal – a major challenge • Closing of Houses followed by testing • Cleaning and Disinfection of houses • Implementation of Biosecurity Measures 28

Carcass Disposal Methods – On Farm Burial – Incineration – Landfill – Composting 29

Biosecurity 30

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Incident Command System • Incident Command Staff • Planning • Administration and Finance • Logistics • Operations 32

Incident Commanders 33

Forest Service 34

Army 35

Department of Health and Human Services 36

Incident Command System Daily Meeting 0700 Surveillance Personnel (All) 0800 Daily Briefing (All w/o Surveillance) 1300 Chiefs Meeting (Commanders and Chiefs) 1800 Planning Meeting (Planning) 1830 Plans Approval Meeting (Commanders and Chiefs) 37

Planning Meeting 38

Morning Briefing 39

Supply 40

Training 41

Surveillance 42

Epidemiological Assessments Proved Critical in Success • Surveillance Design for Commercial Flocks • Surveillance of Backyard Flocks • Surveillance of Wildbirds • Case Control Study • GIS Mapping and Spatial Analysis 43

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AI Case Control Study Preliminary Results Epidemiology Section Analysis team: Jennifer Mc. Quiston Lindsey Garber 46

Risk Factors Assessed: Premises Characteristics - Security - Nearby lake/pond Farm Management - litter source - dead bird disposal Biosecurity - Visitor log - Showers - Disinfectant Footbaths Presence of Other Birds and Animals (wild, domestic) Recent Visitors Recent Travel 47

Case Control Study Assessment of Risk Factors Variable Odds Ratio P Value Use of Renderer 7. 3 <0. 001 Older Birds >10 weeks >4 <0. 001 Use of Non Family Caretakers 2. 1 0. 04 Family Member Working Offsite 2. 0 0. 03 Wild Mammals on Site 1. 9 0. 04 48

Epidemiological Considerations • The source of this outbreak was never established. • The same strain of H 7 N 2 has been seen in other small outbreaks in eastern states and live bird markets in the Northeast over a number of years. • A case-control study found flocks 7 times more likely to be infected if transporting dead birds to a rendering facility. • No evidence was found of airborne spread or spread associated with depopulation or disposal. • Disease was spread primarily by movement of people and equipment in a densely populated poultry rearing area. 49

Lessons Learned ü The H 7 N 2 strain that has circulated among Live Bird Markets of the Northeast and their supply and distribution channels continues to represent a serious threat to commercial poultry. ü Control measures need to be taken to lessen the spread of this virus and further protect commercial flocks. ü Rendering practices need to be reexamined with respect to the risk of disease spread. ü During an outbreak biosecurity measures at the farm and plant level must be strengthened to prevent disease spread by people and equipment. 50

Reasons for Success • Lessons Learned from the Past • Industry Involvement and Commitment • Cooperation Between Virginia, West Virginia, USDA and all of the Cooperators • Improved Technologies (Rapid Diagnosis and Computer Support) • Rapid and Coordinated Response 51

AI Vaccination: Poultry • Non H 5/H 7 AI vaccines routinely used in some areas • H 5/H 7 vaccines traditionally not used because of trade restrictions • Usage of H 5/H 7 vaccines requires USDA and State Approval 52

AI Vaccination: Poultry • 2003 Connecticut H 7 N 2 Outbreak Controlled and Eradicated utilizing H 7 N 3 vaccine, intense biosecurity, and controlled slaughter 53

AI Vaccination: Human • Animal Health responders must be included in targeted human vaccination in zoonotic outbreak involving poultry. • Poultry workers in outbreak area of any zoonotic AI should also be included as priority for vaccination. 54

Commercial Poultry in Florida

Added Animal Health Concerns with Zoonotic AI • Farm workers may introduce disease to poultry • Birds may serve as reservoir with on-going human and bird exposure • Personal safety of Animal Task Force Workers and Poultry Caretakers 56

Added Animal Health Concerns with Zoonotic AI • Humane care and euthanasia of birds • Carcass Disposal, Biosecurity, and Environmental Safeguards • Rapid Detection and Prevention of Spread 57

Florida Department of Agriculture and Consumer Services Charles Bronson, Commissioner AVIAN INFLUENZA An Animal Health Perspective Presented by: Dr. Thomas J. Holt State Veterinarian/Director Division of Animal Industry Phone: 850 -410 -0900 Email: holtt@doacs. state. fl. us