Dr. E. Kwok administers a COVID-19 vaccine to a recipient at a vaccination clinic run by Vancouver Coastal Health, in Richmond, B.C., Saturday, April 10, 2021. THE CANADIAN PRESS/Jonathan Hayward

Dr. E. Kwok administers a COVID-19 vaccine to a recipient at a vaccination clinic run by Vancouver Coastal Health, in Richmond, B.C., Saturday, April 10, 2021. THE CANADIAN PRESS/Jonathan Hayward

NACI says you can mix-and-match AstraZeneca, mRNA COVID vaccines

People who received AstraZeneca vaccine will have a choice for dose two

The National Advisory Committee on Immunization announced Tuesday (June 1) that Canadians who received AstraZeneca for their first dose can get an mRNA vaccine for their second dose.

“I think it’s good news that people now have that choice,” said chief medical health officer Dr. Theresa Tam.

The advice affects more than two million Canadians who received the Oxford-AstraZeneca vaccine before provinces stopped using it for first doses last month.

The vaccine is potentially linked to a rare but serious blood clotting syndrome.

In Canada, 41 confirmed or suspected cases of vaccine-induced thrombotic thrombocytopenia have been diagnosed and five people have died.

NACI’s published report says AstraZeneca recipients can be offered the same vaccine if they want it, or can be given either Pfizer or Moderna.

They say they are basing their advice on the risk of VITT, and emerging evidence that mixing and matching different types of vaccines is not only safe but may produce a better immune response.

The guidance is not binding but most provincial governments have indicated they were waiting for the information before setting their policies for second doses.

Manitoba didn’t wait for the report to be published, announcing Monday they would offer AstraZeneca recipients Pfizer or Moderna if they wanted.

Quebec currently recommends getting the same vaccine twice but says with informed consent people who got AstraZeneca first can get Pfizer or Moderna.

The province is expected to update this later in the week, along with shortening the wait to get second doses of mRNA vaccines.

NACI’s advice comes after interim results were published in May from two studies looking at mixing and matching vaccines.

A Spanish study concluded a second dose of Pfizer after a first dose of AstraZeneca produced more than twice the antibodies as a second dose of AstraZeneca.

A United Kingdom study reported there were more frequent reports of short-lived side-effects such as fever and fatigue in people whose second dose was a different vaccine. It is still waiting for results on how effective mixing and matching is but as second doses ramp up across Canada, health officials say they need to make decisions now.

Several European countries are giving Pfizer or Moderna as second doses to AstraZeneca recipients, including Denmark, Finland, France, Germany, Sweden, Norway and Spain.

More than two-thirds of Canadians over the age of 12 now have at least their first dose, but only about 10 per cent of them are fully vaccinated. With vaccine supplies limited in the first months of the immunization program, provinces delayed second doses up to four months to try and get more people one dose faster.

The plan has worked to that end, with Canada now one of the most vaccinated countries in the world when it comes to first doses. As of May 30, Canada is now in the top 10 countries for first doses in the world, and is likely to surpass the United Kingdom on first doses by the end of the week.

It’s not even in the top 50 for second doses.

Second doses are starting to be given faster now, with several provinces moving to fully vaccinate the highest risk populations, including seniors and those with compromised immune systems.

Until a week ago, fewer than one-tenth of new doses given out each were for second doses, but over the last week one-sixth of new doses were for second shots.

For some people, getting a different second dose is a supply issue, particularly for Moderna recipients, with that company unable to deliver expected doses on time so far.

For AstraZeneca however it is a question of safety. Provinces stopped using AstraZeneca for first doses in mid-May as the number of Canadians diagnosed with vaccine-induced thrombotic thrombocytopenia grew.

The rare blood clotting disorder believed to be caused by an unexpected immune response to the AstraZeneca vaccine, has occurred in about one in every 53,000 Canadians given the AstraZeneca vaccine as a first dose.

While health experts say the risks of the clots is extremely low and is outweighed by the risks of COVID-19, NACI said people should only get AstraZeneca if they are over the age of 30, and live in an area where they are more likely to be exposed to the virus that causes COVID-19.

Many provinces have been holding off giving second doses of AstraZeneca pending NACI’s advice on whether it should be given as second doses.

NACI has already said people can mix and match vaccines within the same vaccine family — so the mRNA vaccines from Pfizer and Moderna can be mixed and matched, or the viral vector vaccines from AstraZeneca and Johnson & Johnson.

That latter advice was theoretical since Canada hasn’t started using the J&J vaccine at this point. The 300,000 doses received in April remain in quarantine in freezers at Innomar Strategies pending a quality assurance check.

The drug substance in those doses was made at a facility in Maryland that has since been cited for numerous safety violations.

More to come.


Like us on Facebook and follow us on Twitter.

Coronavirusvaccines

Just Posted

An example of the forest land in the Port Renfrew and Fairy Creek area of Vancouver Island is shown on May 11, 2021. THE CANADIAN PRESS/Jen Osborne
Old-growth logging opponents launch hunger strike as arrests continue at Fairy Creek

Zain Haq says the hunger strikers will gather today at Burrard Street in downtown Vancouver

An example of the forest land in the Port Renfrew and Fairy Creek area of Vancouver Island is shown on May 11, 2021. THE CANADIAN PRESS/Jen Osborne
Old-growth logging opponents launch hunger strike as arrests continue at Fairy Creek

Zain Haq says the hunger strikers will gather today at Burrard Street in downtown Vancouver

Grade 12 students Sophia Kazakoff and Catherine Yuan accept QMS’s Stigma Free Designation award from Stigma-Free Society president, Andrea Paquette. (Submitted)
Duncan’s QMS earns ‘Stigma-Free’ designation

“No school in the province has accomplished what QMS did in such a short period of time”

“About a year after it was last used for a bottle drive, Lake Cowichan’s derelict Scout and Guide Hall came down Monday, June 6. Girl Guides have since moved into different churches and halls around the area. Town council has yet to decide what will be done with the now vacant town-owned site.” (Tyler Clarke/Lake Cowichan Gazette, June 8, 2011)
Flashback: A.B. Greenwell, Lady of the Lake, good and bad news for the Lake News

What was making headlines this week around Cowichan Lake in years gone by

Conner Gilkin, 5, shows of some of his newfound loot to buddy Jax Dul, 7, during the Lake Cowichan treasure hunt on Saturday, June 5. (Kevin Rothbauer/Gazette)
Weekly hunt has Lake Cowichan digging for treasure

Gold? Silver? Candy? Andrew Braye has stashed away a range of prizes for eager treasure hunters

Canadian Prime Minister Justin Trudeau participates in a plenary session at the G7 Summit in Carbis Bay, England on Friday June 11, 2021. THE CANADIAN PRESS/Adrian Wyld
Canada donating 13M surplus COVID-19 vaccine doses to poor countries

Trudeau says the government will pay for 87 million shots to be distributed to poor countries

Premier John Horgan speaks as provincial health officer Dr. Bonnie Henry, right, and health minister Adrian Dix look on during a press conference to update on the province’s fall pandemic preparedness plan during a press conference from the press theatre at Legislature in Victoria, Wednesday, Sept. 9, 2020. THE CANADIAN PRESS/Chad Hipolito
B.C. officials to provide details on Step 2 of COVID reopening plan Monday

Step 2 could allow for larger gatherings and a resumption of recreational travel

Cannabis bought in British Columbia (Ashley Wadhwani/Black Press Media)
Is it time to start thinking about greener ways to package cannabis?

Packaging suppliers are still figuring eco-friendly and affordable packaging options that fit the mandates of Cannabis Regulations

Indigenous Services Minister Marc Miller is seen during a news conference, Wednesday May 19, 2021 in Ottawa. THE CANADIAN PRESS/Adrian Wyld
Indigenous child-welfare battle heads to court despite calls for Ottawa to drop cases

Feds are poised to argue against two Canadian Human Rights Tribunal rulings

The Great Ogopogo Bathtub Race has been held in Summerland as a fundraising event. Do you know which Canadian city introduced this sport? (Black Press file photo)
QUIZ: A summer’s day at the water

How much do you know about boats, lakes and water?

Two-year-old Ivy McLeod laughs while playing with Lucky the puppy outside their Chilliwack home on Thursday, June 10, 2021. (Jenna Hauck/ Chilliwack Progress)
VIDEO: B.C. family finds ‘perfect’ puppy with limb difference for 2-year-old Ivy

Ivy has special bond with Lucky the puppy who was also born with limb difference

A million-dollar ticket was sold to an individual in Vernon from the Lotto Max draw Friday, June 11, 2021. (Photo courtesy of BCLC)
Lottery ticket worth $1 million sold in Vernon

One lucky individual holds one of 20 tickets worth $1 million from Friday’s Lotto Max draw

“65 years, I’ve carried the stories in my mind and live it every day,” says Jack Kruger. (Athena Bonneau)
‘Maybe this time they will listen’: Survivor shares stories from B.C. residential school

Jack Kruger, living in Syilx territory, wasn’t surprised by news of 215 children’s remains found on the grounds of the former Kamloops Indian Residential School

Most Read