The Public Health Agency of Canada (PHAC) says it has secured an initial supply of half a million doses of a human vaccine against avian influenza as part of its contingency planning around the ongoing outbreak of the highly-pathogenic H5N1 virus.
As of last week, 68 human cases of avian influenza had been reported in the U.S. since the start of 2024, with one human case in Canada. A small portion of these cases have been severe, including the lone Canadian case in a teenager in B.C. in November, and one death in Louisiana. Most of the cases in the U.S. have involved people who work with poultry or dairy cattle.
On Feb. 19, PHAC said it had leveraged an existing agreement to secure 500 thousand doses of GSK’s human vaccine for avian influenza — ArepanrixTM H5N1 A/American wigeon clade 2.3.4.4b.
60 per cent of the doses will go to the provinces and territories, with 40 per cent kept in a federal stockpile.
Canada’s National Advisory Committee on Immunization (NACI) is not recommending broad deployment of the vaccine at this time as the risk to the general public is low, but the committee has provided recommendations for possible use by provincial and territorial health authorities to protect individuals with higher risk of exposure to the virus.
“While it is not possible to predict exactly what will happen with this virus, the committee has identified some epidemiological scenarios and populations where human avian influenza A(H5N1) vaccine could be considered,” says Dr. Robyn Harrison, NACI chair.
The recommendations would see the vaccine deployed to the following groups, in order of priority:
- People who handle live avian influenza virus in laboratory settings.
- People with ongoing contact with known infected birds and their environments, including those involved in culling, workers and residents on poultry and dairy farms with active outbreaks, veterinarians, researchers, and wildlife officers.
- People who work or live on farms with geographic and other connections to farms experiencing outbreaks, including workers in a primary control zone, workers with shared suppliers or equipment, and people with exposure to raw milk from an infected farm.
- Larger populations with exposure to birds and other animals that can be infected, including people who work on poultry and livestock farms, slaughterhouse workers, livestock and poultry transport drivers, wildlife officers and researchers, veterinary workers, hunters and trappers, people who process wild birds and game, and people with backyard flocks.
The latest figures from the Canadian Food Inspection Agency (CFIA) show nearly 14.5 million birds on farms have been affected by the virus — either killed by it, or euthanized after the flock tested positive to minimize the spread — since early 2022. As of last month, there were 35 active cases, mostly in B.C.
Meanwhile, the CFIA says the avian influenza virus found in dairy cattle in many U.S. states has not been detected in Canada.
As of Feb. 20, the U.S. Department of Agriculture says the virus has affected nearly 163 million birds in commercial and backyard flocks in 51 states over the past two years. The Centres for Disease Control says 972 dairy herds in 17 states have also tested positive with a version of the H5N1 virus.
With the political spotlight on rising egg prices, the Trump administration, including U.S. Ag Secretary Brooke Rollins, have repeatedly said ending the disease outbreak is a top priority.
At the same time, multiple media outlets reported this week that the USDA was working to reverse the firing of employees working on the response to the avian flu outbreak who were caught up in sweeping cuts across the U.S. public service.
U.S. poultry producers could soon have a new tool in combatting the virus, as the USDA issued its first conditional approval of an avian influenza vaccine for chickens to Zoetis on Feb. 14. The bird vaccine could potentially help in mitigating the spread and impact of the virus on the U.S. poultry flock, while potentially also raising issues around trade, as vaccinated birds can test positive for the virus.
The Canadian government and poultry industry groups have established a taskforce to study the possibility of vaccinating poultry, but a vaccine for poultry is currently not available in Canada.
