The time between new detections of avian influenza in commercial flocks is getting longer, suggesting that the North American outbreak is hitting a plateau. Warmer, drier weather may also be reducing how long avian influenza can survive in the environment. In addition, tightened biosecurity measures have helped control lateral spread of the virus farm to farm. Most of the recent cases have been in backyard flocks, suggesting that virus is being primarily spread by wild birds in the environment.
Ontario is reporting a total of 26 infected flocks (474,000 birds) to date, the most recent being in York Region
on May 18. There have been 20 commercial and six small flocks infected across the province. Seven flocks are from the four Ontario feather boards.
Recovery is underway. Due to the successful completion of specific disease response milestone activities as prescribed by the Canadian Food Inspection Agency (CFIA), reduced movement restrictions have been placed on 24 of the infected zones within the 25 primary control zones (PCZs):
- commercial placements in 19 infected zones (0-3km) are now possible with a CFIA Specific Permit
- 18 infected zones have now been released. This means movement requirements for these 18 sites are the same as the Primary Control Zone (PCZ); and
- one PCZ has been revoked entirely.
Updates on HPAI zones can be found on the CFIA website: Highly pathogenic avian influenza zones - Canadian Food Inspection Agency (canada.ca)
. More information on CFIA permits and conditions needed for movement control can be found here
The HPAI H5N1 virus has infected 95 poultry flocks across 9 Canadian provinces during the five months since its first detection. This has resulted in the death or culling of 1,913,700 birds according to most recent data; only 57% of these were commercial flocks.
Over 362 cases of HPAI have been confirmed in wild birds across all provinces as of May 5, according to current CFIA/NEOC GIS data.
Based on CFIA data provided to the World Organization of Animal Health (OIE) from 93 infected flocks as of May 27, FBCC has compiled the following information:
- commercial ducks make up 16% of infected flocks and 23% of total birds;
- turkeys make up 12% of flocks and 11% of birds;
- broiler chickens make up 10% of flocks and 32% of birds;
- broiler breeders make up 8% of the infected flocks and 19% of the total birds lost;
- layers (commercial and research) make up 4% of flocks and 7% of birds;
- mixed commercial make up 7% of flocks and 7% of birds; and
- other production types (game and exhibition birds) make up the remainder.
About 38 million birds have died or been depopulated across 35 US states since the first case on February 7. As of May 31, 356 flocks have been affected, 183 of them commercial flocks. (USDA web site
). Approximately 80% of the US flocks infected during May were backyard flocks. APHIS has mobilized 1,125 employees to assist state officials’ response to the US outbreak. The US government has provided new funding of $793 million.
This US National Wildlife Health Centre map
shows the continental distribution of HPAI H5N1 cases in commercial poultry, small flocks, wild birds and mammals across North America.
International AI Situation
Since the onset of this avian flu season in October 2021, more than 60 countries in Europe, Africa, Asia and the Americas have experienced H5N1 HPAI outbreaks. A total of 3,741 infected flocks have been affected since the fall of 2021. Close to 107.47 million birds have died or were depopulated globally in order to eradicate the virus to date. Monthly data by country has been compiled by the FBCC and is posted on the FBCC website
There is generally a decreasing trend in the number of HPAI infected poultry premises over the last two months in Europe, except for Hungary where 141 new infected commercial foie-gras ducks or geese farms across three counties in the south and northeast of the country were reported.
For this year to date, 1,746 infected wild birds have been reported in Europe; half of them in Germany.