OIE: Low pathogenic avian influenza (poultry, H7N3), United States of America

Information received on 16/03/2020 from Dr Mark Davidson, Associate Administrator, USDA-APHIS, United States Department of Agriculture, Washington, United States of America
Summary
Report type Immediate notification
Date of start of the event 10/03/2020
Date of confirmation of the event 12/03/2020
Report date 16/03/2020
Date submitted to OIE 16/03/2020
Reason for notification Recurrence of a listed disease
Date of previous occurrence 30/08/2019
Manifestation of disease Clinical disease
Causal agent Low pathogenic avian influenza virus
Serotype H7N3
Nature of diagnosis Laboratory (advanced)
This event pertains to a defined zone within the country
New outbreaks (3)
Outbreak 1 Union County, Union, North Carolina
Date of start of the outbreak 10/03/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Farm
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Birds 59300 0
Affected population Commercial turkey meat flock
Outbreak 2 Anson County, Anson, North Carolina
Date of start of the outbreak 10/03/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Farm
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Birds 18000 0
Affected population Commercial turkey breeder flock
Outbreak 3 Union County, Union, North Carolina
Date of start of the outbreak 10/03/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Farm
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Birds 12900 0
Affected population Commercial turkey meat flock
Summary of outbreaks Total outbreaks: 3
Total animals affected
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Birds 90200 ** 0
Outbreak statistics
Species Apparent morbidity rate Apparent mortality rate Apparent case fatality rate Proportion susceptible animals lost*
Birds ** ** ** **
*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 As part of routine surveillance for H5/H7 Avian Influenza, H7 low pathogenic avian influenza (LPAI) was detected in a commercial turkey breeder and two turkey meat flocks. Sequencing determined subtype/pathotype of H7N3 on all premises. Clinical signs noted: slight drop in egg production in turkey breeder flock. Plan for confirmed positive flocks is euthanasia (foam method) and disposal. The USDA Animal Plant Health Inspection Service (APHIS) and the North Carolina Department of Agriculture are conducting a comprehensive epidemiological investigation and have implemented enhanced surveillance and testing related to this finding. Five additional commercial poultry premises have been quarantined and sampled for avian influenza virus. Results are pending.
Control measures
Measures applied
  • Movement control inside the country
  • Surveillance within containment and/or protection zone
  • Quarantine
  • Zoning
  • Vaccination prohibited
  • No treatment of affected animals
Measures to be applied
  • Disinfection
Diagnostic test results
Laboratory name and type Species Test Test date Result
National Veterinary Services Laboratory (National laboratory) Birds gene sequencing 12/03/2020 Positive
National Veterinary Services Laboratory (National laboratory) Birds real-time reverse transcriptase/polymerase chain reaction (RRT-PCR) 12/03/2020 Positive
Future Reporting
The event is continuing. Weekly follow-up reports will be submitted.