AVIAN INFLUENZA (LPAI), POULTRY - USA (02): (KENTUCKY)

20,000 slaughtered for naught

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A ProMED-mail post

ProMED-mail is a program of the
International Society for Infectious Diseases


Date: 9 Apr 2009
Source: OIE WAHID [edited]



Low pathogenic avian influenza (poultry), United States of America
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Information received on 6 Apr 2009 from Dr John Clifford, Deputy
Administrator, Animal and Plant Health Inspection Service, United
States Department of Agriculture, Washington, United States of America

Summary
Report type Immediate notification
Start date 31 Mar 2009
Date of 1st confirmation of the event 31 Mar 2009
Report date 6 Apr 2009
Date submitted to OIE 6 Apr 2009
Reason for notification Recurrence of a listed disease
Date of previous occurrence October 2008
Manifestation of disease Sub-clinical infection
Causal agent Low pathogenic avian influenza virus Serotype H7N9
Nature of diagnosis Laboratory (advanced)
This event pertains to a defined zone within the country

New outbreaks

Outbreak 1 - Grayson County, Grayson County, Kentucky
Date of start of the outbreak 31 Mar 2009
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Farm

Affected animals: Species Birds
Susceptible 20 000
Cases -
Deaths - 0
Destroyed 20 000
Slaughtered 0

Affected population A commercial poultry broiler-breeder operation
consisting of 2 poultry broiler-breeder houses with 20 000 birds that
were 49 weeks old.

Summary of outbreaks
Total outbreaks: 1
Outbreak statistics:
Species Birds
Apparent morbidity rate **
Apparent mortality rate 0.00 percent
Apparent case fatality rate **
Proportion susceptible animals lost* 100.00 percent

* Removed from the susceptible population through death, destruction
and/or slaughter
** Not calculated because of missing information

Epidemiology
Source of the outbreak(s) or origin of infection *Unknown or inconclusive

Epidemiological comments
31 Mar 2009: a National Poultry Improvement Plan (NPIP) laboratory
reported seropositive results for avian influenza. The birds were
being tested as part of the NPIP Avian Influenza.

Clean Program (H5 and H7) for breeding facilities. No clinical signs,
other than a modest drop in egg production, were reported. There was
no increase in mortality.

1 Apr 2009: Enhanced surveillance at the broiler-breeding operation
was implemented, and additional laboratory samples were taken.

There were no clinical indications of disease at the time of
diagnostic testing.

2 Apr 2009: The National Veterinary Services Laboratory (NVSL)
confirmed H7 RRT-PCR and hemagglutinin subtype as H7 positive.

Laboratory testing is continuing, but to date, no virus has been isolated.

Kentucky State animal health officials, in coordination with USDA
APHIS Veterinary Services, implemented the LPAI response plan in
accordance with the Kentucky Initial State Response and Containment
Plan for H5 and H7 LPAI.

Implementation included:
An enhanced surveillance zone of 10 km (6.2 miles) was implemented as
outlined in the plan. There are 4 farms, all breeder facilities and
all owned by the same company, within the 10-km radius of the
positive premises. Laboratory samples were collected and submitted
from all 4 farms. Surveillance of backyard poultry flocks is being
conduced within a 3-km (2-mile) radius of the premises.

4 Apr 2009: NVSL reported that sera tested by hemagglutination
inhibition test and neuraminidase inhibition test were seropositive
for H7N9

4 Apr 2009: As a precautionary measure, all birds in the 2 houses
were depopulated.

5 Apr 2009: All laboratory samples collected from the enhanced
surveillance on the 4 breeding facilities yielded negative laboratory
results for avian influenza.

Note by the OIE Animal Health Information Department: H5 and H7 avian
influenza in its low pathogenic form in poultry is a notifiable
disease as per Chapter 10.4. on avian influenza of the Terrestrial
Animal Health Code (2008).

Control measures:

Measures applied:
* Stamping out
* Quarantine
* Zoning
* Vaccination prohibited
* No treatment of affected animals

Measures to be applied:
* Disinfection of infected premises/establishment(s)

Diagnostic test results

Laboratory name and type National Poultry Improvement Plan (NPIP)
laboratory (Local laboratory)
Tests and results:
Species - Test - Test date - Result
Birds - agar-gel immunodiffusion (AGID) - 31 Mar 2009 - Positive

Laboratory name and type National Veterinary Services Laboratory
(NVSL) (National laboratory)
Tests and results:
Species - Test - Test date - Result
Birds - agar-gel immunodiffusion (AGID) - 5 Apr 2009 - Negative
Birds - enzyme-linked immunosorbent assay (ELISA) - 5 Apr 2009 - Negative
Birds - hemagglutination inhibition test (HIT) - 4 Apr 2009 - Positive
Birds - neuraminidase inhibition assay - 4 Apr 2009 - Positive
Birds - real-time reverse transcriptase/polymerase chain reaction
(RRT-PCR) - 2 Apr 2009 - Positive
Birds - real-time reverse transcriptase/polymerase chain reaction
(RRT-PCR) - 4 Apr 2009 - Positive

Future Reporting
The event is continuing. Weekly follow-up reports will be submitted.

--
Communicated by:
ProMED-mail Rapporteur Susan Baekeland

[Note that not a single bird was sick; this "outbreak" was detected by
serological surveillance, and cost the company 20 000 broiler-breeders
culled.
- Mod.JW]

[see also:
Avian influenza (LPAI), poultry - USA (KY): H7 20090405.1314
2008
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Avian influenza, LP: USA (ID), H5N8, pheasant, OIE 20080905.2771
Avian influenza (H7N3) - USA: (RI) 20080821.2611
Avian influenza (72): USA (AR), LPAI H7 20080604.1782
2007
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Avian influenza, LP, turkeys - USA (VA) (02) 20070713.2257
Avian influenza, LP, turkeys - USA (VA) 20070709.2191
Avian influenza, H5N2, turkeys - USA (WV) (02): OIE 20070403.1133
Avian influenza, H5N2, turkeys - USA (WV) 20070403.1128
2006
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Avian influenza, LP, wild avians - USA (NY) 20061102.3146
Avian influenza, LP, wild avians - USA (MI) 20061021.3028
Avian influenza, H6N2, wild avians - USA (IL): LP conf 20061018.2988
Avian influenza, wild birds - USA (OH): low path susp. 20061015.2973
Avian influenza, wild birds - USA (MT)(02): low path conf 20061009.2893
Avian influenza, wild birds - USA (IL): low path 20060930.2804
Avian influenza, mallards - USA (PA)(02): LP, USDA/DOI 20060927.2756
Avian influenza, mallards - USA (MD)(02): LP, USDA report 20060913.2589
Avian influenza, mute swan - USA (MI) (02): LP conf 20060830.2463]
..................................................tg/msp/jw