#18,630
As concerns over the evolution and spread of the HPAI H5 virus increase, countries around the world have begun to purchase varying amounts of pre-pandemic H5 vaccines for their populations. Some of these vaccines are based on older strains of the virus, while others are based on more recent strains.
Whether - or how closely - they will match any emerging pandemic strain is unknown, which is why most countries have elected to purchase only enough for high-risk individuals.
The United States ordered about 4.8 million doses last summer, enough for about 2.4 million people. In 2023 Japan announced plans to stockpile about 10 million doses. While last December the UK announced plans to purchase 5 million doses.
Today Canada's Public Health Agency announced plans to purchase 500,000 doses of GSK’s human vaccine against avian influenza; ArepanrixTM H5N1 A/American wigeon clade 2.3.4.4b.
I've reproduced their press release below. I'll have a bit more after the break.
Government of Canada purchases avian influenza vaccine to protect individuals most at risk
From: Public Health Agency of Canada
News release
February 19, 2025 | Ottawa, ON | Public Health Agency of Canada
The Public Health Agency of Canada (PHAC) and its partners are focused on keeping people and animals in Canada safe and ensuring Canada is ready for any potential health threats. This includes taking proactive measures to protect the health of people in Canada by authorizing and securing the supply of a human vaccine against avian influenza as part of our readiness and potential use, as needed, based on risk conditions. Leveraging an existing agreement, PHAC has secured an initial supply of 500,000 doses of GSK’s human vaccine against avian influenza – ArepanrixTM H5N1 A/American wigeon clade 2.3.4.4b. This vaccine will be used as part of Canada’s contingency planning to protect people who may be at increased risk of being exposed to the virus through animals infected with avian influenza.
While the current risk to the public remains low, individuals with higher-level exposure to infected animals are at increased risk and should take appropriate precautions. Canada reported its first domestically acquired human case of avian influenza A(H5N1) on November 9, 2024, and continued vigilance will help prevent additional human cases. To date, there has been no evidence of sustained person-to-person spread of the virus in any of the cases identified globally. However, avian influenza has the potential to cause serious illness in people.
PHAC will provide vaccines to provinces and territories based on an equitable and risk-based approach, with 60% of available doses going to provinces and territories and 40% kept in a federal stockpile for national preparedness. Provinces and territories will make decisions on the potential use and administration of their respective vaccination programs in the context of local risk conditions, with PHAC supporting program monitoring and evaluation to adjust national efforts as needed.
Canada’s National Advisory Committee on Immunization (NACI) has also released preliminary guidance on the use of human vaccines against avian influenza in a non-pandemic context. Based on the evolving epidemiological situation in Canada and the United States, broad vaccine deployment is not recommended at this time but the guidance provides recommendations for the possible use of this vaccine by provincial and territorial public health authorities in current and potential future scenarios to protect the health of individuals at increased risk of being exposed to the virus.
PHAC continues to work closely with the Canadian Food Inspection Agency, Health Canada, provincial and territorial public health authorities, animal health leaders and experts, industry groups, and international organizations to prepare for and manage the global risks of avian influenza. We remain committed to protecting Canadians by continuously strengthening our preparedness for emerging issues, such as avian influenza, through proactive measures including risk assessments, lab capacity and testing, monitoring and surveillance, science coordination and expert engagement, as well as guidance for professionals and the public.
Quotes
“As we confront the ongoing global health risks posed by avian influenza, our priority remains protecting the health of people in Canada. The proactive steps we are taking, including securing vaccine doses, reflect our commitment to being prepared for any potential public health threats.”
The Honourable Mark Holland
Minister of Health
“By making human vaccines against avian influenza available for potential use in individuals at increased risk of exposure to avian influenza as part of our readiness, we are enhancing our capacity to protect people in Canada and respond rapidly to emerging public health challenges.”
Dr. Theresa Tam
Chief Public Health Officer
Quick facts
- Avian Influenza A(H5N1) may pose a higher risk to individuals who have ongoing contact with infected animals and their environments, including poultry.
- The Arepanrix H5N1 A/American wigeon clade 2.3.4.4b vaccine is based on established technology for seasonal and pandemic influenza vaccines. Health Canada completed the review of the regulatory submission on February 18, 2025 and authorized the vaccine strain change.
None of these purchases is intended to protect an entire population, as it is expected to take 2 doses - 30 days apart - to convey immunity. With a population of nearly 40 million, Canada would need nearly 80 million doses while the United States would need over 600 million.
- The National Advisory Committee on Immunization provides expert guidance on vaccine use in Canada. Their guidance on the use of Arepanrix H5N1 A/American wigeon clade 2.3.4.4b vaccine can be found on Canada.ca.
Today's announcement does not provide a time-table for manufacture or delivery, but it generally takes several months to manufacture, fill and finish.Having some quantity of pre-existing vaccine on hand, however, could allow certain high risk individuals (like farmers or HCWs) to be partially protected, while an updated vaccine is being developed.
