Low pathogenic avian influenza (poultry),
United States of America
Information received on 27/04/2020 from Dr Mark Davidson, Associate Administrator, USDA-APHIS, United States Department of Agriculture, Washington, United States of America
Report type Follow-up report No. 4
Date of start of the event 10/03/2020
Date of confirmation of the event 12/03/2020
Report date 27/04/2020
Date submitted to OIE 27/04/2020
Date event resolved 21/07/2020
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
Related reports Immediate notification (16/03/2020)
Follow-up report No. 1 (24/03/2020)
Follow-up report No. 2 (06/04/2020)
Follow-up report No. 3 (14/04/2020)
Follow-up report No. 4 (27/04/2020)
Follow-up report No. 5 (07/05/2020)
Follow-up report No. 6 (18/05/2020)
Follow-up report No. 7 (21/05/2020)
Follow-up report No. 8 (05/06/2020)
Follow-up report No. 9 (26/06/2020)
Follow-up report No. 10 (24/07/2020)
Outbreaks There are no new outbreaks in this report
Source of the outbreak(s) or origin of infection
  • Unknown or inconclusive
Epidemiological comments 27 Apr 2020 Update--All enhanced surveillance testing including targeted network surveillance has been negative as of 15 Apr 2020. Disposal efforts were completed on one affected North Carolina premises on 19 Apr 2020 and continue on the other ten affected North Carolina premises. Disposal was also completed on the one affected South Carolina premises on 19 Mar 2020. Routine passive and active surveillance for the National Poultry Improvement Plan (NPIP) avian influenza programs is ongoing statewide in North Carolina and South Carolina. The USDA Animal and Plant Health Inspection Service (APHIS) and Animal Health Officials in affected states continue their comprehensive epidemiological investigation. Based on sequencing information for all H7N3 North Carolina/South Carolina (NC/SC) cases, data supports a single virus introduction followed by secondary spread. Sequencing information also supports that H7N3 LPAI NC/SC viruses are: 1. distinct from other recent H7 events in poultry, and have not previously been detected in poultry 2. similar to other wild bird viruses, sharing a common HA ancestry with those from 2016-2018 3. North American wild bird-origin viruses
Control measures
Measures applied
  • Movement control inside the country
  • Surveillance within containment and/or protection zone
  • Quarantine
  • Stamping out
  • Zoning
  • Vaccination prohibited
  • No treatment of affected animals
Measures to be applied
  • Disinfection
Future Reporting
The event is continuing. Weekly follow-up reports will be submitted.