Remarks from the Chief Public Health Officer of Canada on June 1, 2021


June 1, 2021               Ottawa, ON                 Public Health Agency of Canada 

The COVID-19 pandemic continues to create stress and anxiety for many Canadians, particularly those who do not have ready access to their regular support networks. Through the Wellness Together Canada online portal, people of all ages across the country can access immediate, free and confidential mental health and substance use supports, 24 hours a day, seven days a week.

Nationally, the steady decline in COVID-19 disease activity continues. The latest 7-day average is now below 2,700 cases reported daily, which is a 70% decrease from the peak of the third wave. With the considerable decline in infection rates, the number of people experiencing severe and critical illness has also declined. The latest 7-day average for the number of people with COVID-19 being treated in our hospitals each day has dropped 40% since the peak to about 2,600 daily. Of these, on average, under 1,100 were being treated in intensive care units, down 25% since the peak, and average daily deaths are also down 25% to 39 deaths being reported daily.

Although the long months of this pandemic have been difficult, Canadians have worked together to get through the hardest parts, overcome the challenges of the many uncertainties we've encountered, and stepped up to do their part at every turn. This is perhaps no more evident than now, with vaccine uptake increasing in leaps and bounds, as supplies have increased and roll out expands.

At the same time, Canada's dedicated and diverse health and research professionals have continued to monitor vaccine safety, evaluate effectiveness and assess the latest evidence on COVID-19 vaccines and vaccination programs in Canada and worldwide. As part of this real-time monitoring and expert review of the latest scientific evidence, Canada's National Advisory Committee on Immunization (NACI) has worked to quickly adapt its guidance on the use of COVID-19 vaccines in Canada to ensure optimal protection of Canadians, at pace with the ever changing circumstances during this pandemic. As always, NACI recommendations are based on the strength of emerging evidence overtop of a strong foundation from many decades of experience with vaccine programs in Canada.

NACI's latest guidance, released today, considered a range of factors from safety concerns through vaccine supply to provide recommendations on the safety and effectiveness of the interchangeability of authorized COVID-19 vaccines or 'mixed vaccine schedules' for first and second doses of COVID-19 vaccines. This advice provides provinces and territories with safe and effective options to manage their vaccine programs, specifically advising that:

  • People who received a first dose of the AstraZeneca/COVISHIELD vaccine may receive either AstraZeneca/COVISHIELD vaccine or an mRNA, Pfizer-BioNTech or Moderna, vaccine for their second dose, unless contraindicated.
  • People who received a first dose of an mRNA, Pfizer-BioNTech or Moderna, vaccine should be offered the same mRNA vaccine for their second dose, but if the same mRNA vaccine is not readily available or unknown, another mRNA vaccine can be considered interchangeable and should be offered to complete the vaccine series.

In short, the interchangeability of vaccines means you can receive one vaccine product for your first dose and safely receive a different vaccine for your second dose to complete your two-dose vaccine series for optimal protection from COVID-19.
While NACI continues to recommend that jurisdictions maximize the number of individuals benefiting from the first dose of a COVID-19 vaccine by extending the interval between doses up to four months, in the context of increasing COVID-19 vaccine supply in Canada, the Committee recommended last week that second doses be offered as soon as possible. NACI recommends that priority for second doses should be given to those at highest risk of severe illness and death from COVID-19 disease after – or at the same time as – first doses are offered to all remaining eligible populations. NACI continues to closely monitor the effectiveness of extending dose intervals and will update recommendations as needed.

Canada's regulatory, public health, medical and research professionals remain dedicated to working together to closely monitor vaccine safety and effectiveness, while rapidly responding to new evidence to maintain optimal use of vaccines in Canada. As the science and situation evolves, we are committed to providing clear and evidence-informed guidance in order to keep everyone in Canada safe and healthy.

Read my backgrounder to access COVID-19 Information and Resources, including information on vaccination and ways to reduce your risk of infection and spreading the virus to others.


Media Relations
Public Health Agency of Canada

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