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Avian Influenza Surveillance & Response

I. Development of plan of action

Avian influenza control is aimed primarily at birds in commercial poultry flocks to assure that interstate and international export markets remain open. Low pathogenicity avian influenza (LPAI) strains are known to be circulating in the environment and are spread by waterfowl. Antigenic shift or mutation of H5 and H7 LPAI to High Pathogenicity Avian Influenza (HPAI) is known to occur when H5/H7 LPAI is allowed to circulate in large flocks of poultry for extended periods. For this reason, all HPAI and H5/H7 LPAI are now termed Notifiable Avian Influenza (NAI) and must be reported to state and federal authorities and the OIE. Development of surveillance and response plans involve members of the following groups:
  • Commercial poultry producers and their veterinarians
  • Oregon Department of Agriculture (ODA), Animal Health Program
  • Oregon State University Extension Poultry Specialist
  • USDA, APHIS, VS (USDA, Animal plant health inspection service, vet services)
  • Oregon Emergency Management (OEM)
  • Oregon Public Health Department
  • College of Veterinary Medicine Diagnostic Laboratory
The standing Avian Influenza Emergency Response Group will meet at least once yearly to evaluate this plan and/or to exercise some or all of the elements of the plan. The Response Group includes representatives of the poultry industry, ODA, USDA, OSU-VDL, OSPH and OEM.

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II. Public outreach

As funding permits, the Oregon Department of Agriculture will work to inform the public on the necessity of practicing biosecurity to prevent the infection of one's poultry with AI or Exotic Newcastle Disease (END). This information will be distributed through feed stores, extension service offices, auction markets, other public forums, and producer groups. Basic disease symptoms will also be explained to the public.
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III. Surveillance (Routine monitoring)

Statutory authority is provided to the Oregon Department of Agriculture in ORS 596.020. ODA has the responsibility to "take all measures necessary and proper, in its judgment, to control diseases within this state and to eradicate and prevent the spread of infectious, contagious and communicable diseases that may exist among livestock and to prevent the entry into this state of animals or materials liable to convey infectious, contagious and communicable disease to the livestock or people of this state". Within this general authority is the ability to cause testing and diagnostic procedures and to control and eradicate exotic and emergency diseases. Both active and passive surveillance methods must be used to monitor for presence of avian influenza in the state in order for commercial poultry producers to qualify for 100% indemnity as outlined in 9CFR Parts 53, 56, 145, 146, 147 LPAI Voluntary Control Program and Payment of Indemnity.
  • Active AI virus surveillance will be carried out as outlined in the above CFR. Adherence to this program shall facilitate federal assistance and indemnity in the event of an H5 or H7 LPAI outbreak. To date, all HPAI in poultry have been associated with H5 and H7 subtypes only.
  • Production/health monitoring will also be relied upon for AI surveillance. The flock owners, in consultation with the veterinarian responsible for the flock, shall agree to test for AI virus and AI antibodies in the event of production losses or increased mortality. All AI test results are to be reported to the ODA state veterinarian. (See Appendix C for agreement)
  • ODA may choose to monitor non-commercial flocks (including upland game-bird flocks) in proximity to commercial operations in order to provide a higher level of security for all parties involved.
  • Increased levels of active surveillance may be mandated by ODA in the event of increased perceived risk of AI. Increased perceived risk may include, but is not limited to: AI infections in adjacent states, epidemiologic links between Oregon flock(s) and affected flocks in other states or countries, and/or proximity to an affected flock in Oregon.
  • Appropriate testing methods shall be used for serologic surveillance in live birds or testing for AIV with tracheal or cloacal swabs in live or dead birds. All positive results on screening tests will be confirmed by procedures outlined in directive by John Clifford, Deputy Administrator, USDA-VS and the SOPs written by USDA HPAI Task Force.

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IV. Initial response

Presumptive positive at OSU-VDL (PCR) or ODA Animal Health Lab (ELISA/AGID)
  • AVIC and State Veterinarian are immediately notified
  • Samples are forwarded to NVSL for confirmatory work

Positive H5/H7AI serology (AGID) without increased mortality
  • The test result will be considered a presumptive positive. The flock and/or farm will be placed on a hold order (see Appendix I) and strict biosecurity measures required (see Appendices A and B ). All commercial poultry flock owners will be informed of the status of the hold order. The hold order may not apply to properly sanitized table eggs (washed in water which is at least 20 degrees F warmer than the eggs and then spray rinsed with an approved sanitizing agent).
  • Serum, cloacal and oropharyngeal/tracheal swabs from birds in the infected flock will be immediately forwarded to the National Veterinary Services Laboratory (NVSL) for confirmatory testing following procedures outlined in directive by John Clifford, Deputy Administrator, USDA-VS and the SOPs written by USDA HPAI Task Force. Swabs may be simultaneously sent to OSU VDL for appropriate official testing. (see Appendix J for sampling protocol)
  • NVSL will subtype the antibody and carry out virus isolation for characterization and pathogenicity testing.
  • Initial subtype results should be obtained within 24 to 48 hours and pathogenicity may take between 5 and 20 days.
  • Upon receipt of a presumptive positive result, an investigation will be initiated by ODA/USDA to determine the infected and contact flocks.

Positive H5/H7AI serology accompanied by significant on farm mortality
  • The test result will be considered a presumptive positive. The flock or farm will be placed on a hold order and strict biosecurity measures required. All commercial poultry flock owners will be informed of the status of the flock. See Appendices A and B .
  • An investigation by ODA/USDA will determine infected and contact flocks.
  • A control area of two or more miles around the combined infected and contact premises may be imposed. See Section VII and Appendix B for details of strict quarantine requirements.
  • Tracheal/oropharyngeal and cloacal swabs from affected birds and appropriate tissues from individual dead birds will be sent to NVSL for virus isolation, characterization and pathogenicity testing. Swabs shall be simultaneously sent to OSU VDL for appropriate official results. (See Appendix J for sampling protocol)

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V. Response following definitive diagnosis

With confirmed positive from NVSL
  • AVIC is notified and he then notifies the state veterinarian
  • Appropriate government agencies and poultry producers are notified as noted in the notification pathway schematic in Appendix N.

LPAI subtype H5 or H7
  • Following consultation with USDA and industry parties involved, an infected flock may be depopulated (see Appendices C , D , E and F concerning euthanasia and disposal options). This depopulation may take place as much as two to four weeks after the initial outbreak in order to reduce the amount of virus spread by infected, virus producing birds; and/or
  • Vaccination of a laying flock for a limited period may be used as a method of eradicating the disease. (see Appendix C for sample vaccination protocol) Sequential depopulation of spent hens by slaughter may occur once viral testing and sentinel birds (see Appendix K for sentinel bird protocol) indicate the flock to be without active infection for a period of at least one month; and/or
  • An infected broiler flock which is detected at slaughter shall require complete C&D of production facilities and placement of sentinel birds (AI naïve 16 wk pullets) prior to replacement of broiler chicks; and/or
  • A broiler flock with serologically positive test may be depopulated;
  • A spent laying hen flock serologically positive to LPAI H5/H7 but with no evidence of virus shedding, may be moved to slaughter.
  • All flocks or farms within a two-mile radius of an infected flock may be LPAI H5/H7 tested.
  • Number of birds sampled at each premises will be determined by protocol established by the USDA HPAI Task Force. (see Appendix J for surveillance protocol and HPAI Task Force XVII, pages 189-200).
  • Surveillance will continue weekly until all surrounding flocks or farms have been sufficiently tested. This could be for six to nine weeks past any AIV isolation in the area.


LPAI other subtypes
  • Strict biosecurity measures will be maintained throughout the life of the flock. This may not apply to the sale of appropriately sanitized table eggs.
  • Control measures to be taken are to be presented in writing by poultry producers to ODA State Veterinarian.
  • Surveillance shall be carried out in adjacent or epidemiologically linked flocks until the infection has been shown to be no longer be active. This testing shall be in the form of serology, virus isolation, and RT-PCR and/or sentinel birds. Producers whom have received appropriate training from their veterinarian of record and/or ODA personnel may take surveillance samples.

HPAI
  • HPAI is considered a foreign animal disease and therefore infected flock(s) will be depopulated and indemnified.
  • Appraisal of the flock will occur before depopulation.
  • Surveillance will be carried out in a minimum 2-mile radius from infected flock/premises. Methods of surveillance will be the same as those used for LPAI H5/H7 and/or as outlined in the SOPs of the USDA HPAI Task Force, XVII, pages 187-200.

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VI. Incident command

As soon as a positive test is received by the ODA, they will activate the Oregon Animal Disease Emergency Management Plan. The State Veterinarian and the USDA-APHIS Area Veterinarian In Charge will establish an Incident Command System with a unified command structure. During the first 24-72 hours the following actions will take place.
  • A local incident command post will be established if necessary to assist local emergency planners' and authorities' response to the event.
  • Financial necessities will initially be managed through ODA Administrative Services.
  • ODA Animal Health and Identification and Oregon based USDA Veterinary Services personnel will conduct planning and operational functions.
  • Logistical needs, in terms of facilities, equipment, supplies and personnel, shall be dealt with locally, intra-departmentally and inter-departmentally as deemed appropriate.
  • ODA will follow guideline principles for establishing and maintaining a NIMS as part of the National Avian Influenza Response Plan.

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VII. Development of plans for infected and exposed flocks

A written flock management agreement for infected and exposed flocks shall be developed by the ODA and USDA-APHIS with input from the flock owner and other affected parties. A flock plan sets out the steps to be taken to eradicate the H5/H7 LPAI from a positive flock, or to prevent introduction of H5/H7 into another flock. A flock plan shall include, but is not necessarily limited to, poultry and poultry product movement and geographically appropriate infected and control/ monitoring zones. Control measures in the flock plan should include detailed plans for safe handling of conveyances, containers, and other associated materials that could serve as fomites; disposal of flocks; vaccination when appropriate; cleaning and disinfection; and repopulation.
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VIII. Public relations response/communication

The following will guide public information activities during an Avian Influenza outbreak:
  • ODA will activate the Oregon Animal Disease Emergency Management Plan and inform local emergency managers and industry representatives of the situation.
  • ODA will establish an Incident Command System (ICS).
  • The ODA Public Information Officer (PIO) or appropriate representative will be immediately assigned to the ICS and begin to assemble information for public and agency distribution
  • The PIO will follow procedures as outlined in the ODA.OSPH and ODF&W Emergency Response Joint Information Communications Plan for information gathering and delivery.
  • The PIO shall establish a Joint Information Center and a Public Information Team with the number of members determined by the situation and the PIO. The Public Information Team shall consist of appropriate representatives from ODA, USDA and the poultry industry.
  • The PIO and PI Team will function under the direction of the IC at all times.
  • The PI Team will prepare and electronically maintain a copy of press releases and a time-line (log) of public information activities.
  • The PIO will schedule briefings for the news media as new information becomes available. In some cases briefings may be pre-scheduled to occur at designated times.
  • The State Veterinarian or other designated "expert" shall be available to answer technical questions that may be asked during the briefing.
  • After the outbreak has ended, public information records will be collected by the PIO and filed. All public information media releases will be maintained in an electronic format when possible.


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IX. Quarantine zone or control area

  • Initially, an AGID positive flock without elevated mortality will be placed under a hold order. This quarantine may not affect the sale of properly sanitized table eggs.
  • The hold order shall be lifted when viral and/or sentinel bird testing show the premises to be free of AIV.
  • A quarantine zone, called a control area, of at least two miles (3km) shall be placed around test-positive flocks with significantly elevated mortalities or confirmed LPAI H5 or H7 infection. The control area shall include all contact flocks as well.
  • Confirmed HPAI infected and subsequent contact flocks shall have a control area with a radius of at least two miles established around them.
  • No avian species may be moved out of or into the control area.
  • No poultry products or supplies may be moved off the affected premises or out of the control area (possible exception granted for LPAI without mortalities).
  • Trucks or vehicles entering the affected premises must be thoroughly disinfected before leaving the affected premises.
  • If testing within the initial control area detects additional positive flocks or farms, the area will be extended at least two miles from each infected flock.
  • Quarantine procedures are described in Appendix B, the National AI Response Plan (NAIRP) and the HPAI Task Force standard operating proceduers (SOP)s.
 

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X. Appraisal and indemnification

  • Appraisal by designated and qualified appraisers shall occur immediately before any depopulation when a flock is designated as infected or exposed. If available, commercial flock appraisers shall work with commercial flocks and small flock appraisers will appraise flocks with 1000 birds or fewer.
  • Appraisal shall be accomplished in accordance with the bird's fair market value.
  • Indemnity payments may be less than market value if state or federal indemnity funds are limited.
  • An appeal process is available, if promptly initiated.
  • See the NAIRP and HPAI Task Force SOPs for further details on appraisal procedures.

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XI. Euthanasia

  • Only USDA-APHIS approved methods of euthanasia shall be employed.
  • CO2 gas injected into containers or buildings will be the primary, but not necessarily the only, method of euthanasia. See HPAI Task Force SOPs for additional details.
  • Containers, CO2 and necessary equipment sources are outlined in Appendix F.

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XII. Carcass disposal

  • If depopulation is chosen as the preferred method of dealing with an H/LPAI outbreak, one of three methods may be used for disposal of the birds.
  • In house composting as described in Appendix D may be used for disposal of birds and is the desired method when practical.
  • If composting is not an option, birds may be disposed of in a landfill as described in Appendix E .
  • Small numbers of birds may be buried, incinerated on site or sent to the Brook’s incinerator for disposal (see Appendix E).
  • See USDA HPAI Task Force SOPs for further details.

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XIII. Premises decontamination and disinfection

  • Immediately after depopulation or controlled marketing of the birds, loose feathers shall be gathered and burned. Rodenticides and insecticides shall be applied. Composting of birds and litter may commence as appropriate.
  • The building shall undergo a down-time of at least 21 days and shall be heated to 100 degrees Fahrenheit for the 72 hours prior to cleaning and disinfection (C&D).
  • Manure and all organic material shall be completely removed from infected building, unless in-house composting is to be carried out. The sides of the building shall be scraped to remove all residual organic material that might harbor virus.
  • Manure shall be buried or composted on the premises or double bagged and taken to a designated landfill or incinerator
  • Manure removed more than four months after initial infection, which has been verified virus free, may be handled normally.
  • Cleaning shall be carried out as described in 9CFR 56.5.(d). Equipment shall be disassembled as necessary for cleaning.
  • After cleaning, all surfaces shall be allowed to dry.
  • After drying, the physical facility and equipment shall be appropriately disinfected with Vircon S or other approved disinfectant applied with a power spray unit.
  • Repopulation of the infected premises shall not occur until the premises is declared clean by state and federal animal health officials and appropriate down time has passed. Environmental testing by virus isolation and/or sentinel birds may be required.
  • See the USDA HPAI Task Force SOPs for further details.

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XIV. Surveillance following identification of HPAI or LPAI H5/H7

At risk flocks shall be subject to testing. These could be flocks within six miles of the infected flock or at risk because of an epidemiological link to possible infection. ODA personnel, or specifically trained farm personnel shall collect samples observing appropriate biosecurity and sampling procedures as described in Appendices G and H. See the NAIRP and HPAI Task Force SOPs for further details.
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XV. Monitoring following repopulation of infected premises

All broiler flocks shall be tested by ELISA/AGID and rt-PCR (polymarase chain reaction) within seven days of movement to slaughter. Testing shall be at standard surveillance levels and negative results shall be received prior to movement to slaughter.
All laying flocks shall be tested by AGID/ELISA at one month post installation in a previously infected premises. Thirty birds per flock shall be tested.

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XVI. Controlled marketing of virus negative flocks

Poultry infected with or exposed to H5/H7 LPAI must not be transported to a market for controlled marketing until 21 days after the acute phase of the infection has concluded as determined by ODA and USDA-APHIS. Determination of the end of the acute phase will be based on return to normal mortality levels. Exposure is as defined in pertinent CFR (code of federal regulations).
Flocks to be control marketed must be found virus negative by standard surveillance protocols within seven days prior to slaughter. Test negative flocks within infected zones that have no epidemiologic links to infected flocks may move to slaughter with appropriate biosecurity precautions.
All of the above flocks shall only be moved to slaughter with appropriate biosecurity measures as outlined in the flock management plan.

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