Low pathogenic avian influenza (poultry),
United States of America
Information received on 09/03/2018 from Dr John Clifford, Official Delegate, Chief Trade Advisor, Animal and Plant Health Inspection Service, United States Department of Agriculture, Washington, United States of America
Summary
Report type Immediate notification
Date of start of the event 06/03/2018
Date of confirmation of the event 08/03/2018
Report date 09/03/2018
Date submitted to OIE 09/03/2018
Date event resolved 23/03/2018
Reason for notification Recurrence of a listed disease
Date of previous occurrence 2017
Manifestation of disease Clinical disease
Causal agent Low pathogenic avian influenza virus
Serotype H7N1
Nature of diagnosis Laboratory (basic), Laboratory (advanced)
This event pertains to a defined zone within the country
Related reports Immediate notification (09/03/2018)
Follow-up report No. 1 (27/03/2018)
Follow-up report No. 2 (13/04/2018)
New outbreaks (1)
Outbreak 1 Hopkins county, Hopkins, Texas
Date of start of the outbreak 06/03/2018
Outbreak status Resolved (23/03/2018)
Epidemiological unit Farm
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Birds 24091 0 24091 0
Affected population Commercial broiler breeder flock
Summary of outbreaks Total outbreaks: 1
Total animals affected
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Birds 24091 ** 0 24091 0
Outbreak statistics
Species Apparent morbidity rate Apparent mortality rate Apparent case fatality rate Proportion susceptible animals lost*
Birds ** 0.00% ** 100.00%
*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, pre-slaughter testing and surveillance for H5/H7 avian influenza, H7N1 low pathogenic avian influenza (LPAI) was detected in a commercial broiler breeder flock based upon H7 PCR and antibody to H7 and N1. Partial HA sequencing determined the H7 to be a low pathogenic virus of North American wild bird lineage. Further characterization is pending virus recovery. The flock exhibited a slight increase in mortality and a decrease in egg production. Depopulation of the premises is underway. The USDA Animal Plant Health Inspection Service (APHIS) and the Texas Animal Health Commission are conducting a comprehensive epidemiological investigation of this incident and have implemented enhanced surveillance and testing within 10km of this finding.
Control measures
Measures applied
  • Movement control inside the country
  • Surveillance outside containment and/or protection zone
  • 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
Texas A&M Veterinary Medical Diagnostic Laboratory (Local laboratory) Birds enzyme-linked immunosorbent assay (ELISA) 07/03/2018 Positive
Texas A&M Veterinary Medical Diagnostic Laboratory (Local laboratory) Birds real-time reverse transcriptase/polymerase chain reaction (RRT-PCR) 07/03/2018 Positive
National Veterinary Services Laboratory (National laboratory) Birds enzyme-linked immunosorbent assay (ELISA) 07/03/2018 Positive
National Veterinary Services Laboratory (National laboratory) Birds haemagglutination inhibition test (HIT) 07/03/2018 Positive
National Veterinary Services Laboratory (National laboratory) Birds real-time reverse transcriptase/polymerase chain reaction (RRT-PCR) 08/03/2018 Positive
National Veterinary Services Laboratory (National laboratory) Birds virus isolation Pending
Future Reporting
The event is continuing. Weekly follow-up reports will be submitted.
Map of outbreak locations