Doctors agree with pause of AstraZeneca-Oxford COVID-19 vaccine doses, but Manitobans have questions

Manitoba doctors agree that pausing administration of the AstraZeneca-Oxford COVID-19 vaccine to people under 55 years old is a safe move — but some in the public are puzzled.

Rollout to people under 55 paused after reports of some European patients developing blood clots

Manitoba pharmacies and doctors' offices started receiving doses of the AstraZeneca-Oxford COVID-19 vaccine less than three weeks ago to administer to patients. (Carlos Osorio/The Canadian Press)

Manitoba doctors agree that pausing administration of the AstraZeneca-Oxford COVID-19 vaccine to people under 55 years old is a safe move — but some in the public are puzzled.

Canada's National Advisory Committee on Immunization (NACI) suggested Monday that provinces hold off from injecting the AstraZeneca-Oxford vaccine into the arms of people under 55, following recent reports out of Europe that some patients develop blood clots after receiving the dose.

Dr. Joss Reimer, medical lead for Manitoba's vaccine task force, later announced the province will follow that advice to err on the side of caution.

"The pause, I hope, will send a message of confidence to Manitobans. Vaccines are monitored very closely and even a rare potential issue identified in another country triggers precautions here in Canada to ensure that we stay safe," said Dr. Cory Baillie, president of Doctors Manitoba, which represents over 3,000 physicians across the province.

Had Canada — and Manitoba — not followed through with a pause, it would send conflicting messages about this particular vaccine to the public, said Baillie

There remains little available data on the phenomenon, but the recent data from overseas suggests the risk of blood clots is about one in 100,000, affecting mostly women under age 55.

The potential effects may occur within four to 20 days of receiving the vaccine.

The AstraZeneca-Oxford vaccine started being administered in Manitoba pharmacies and doctors' offices, to patients within specific age ranges with underlying health issues, less than three weeks ago.

So far, there have been no reported cases of blood clots linked to the vaccine in Canada.

"It's not uncommon with all vaccines for these kinds of things to come up," said Dr. Anand Kumar, University of Manitoba professor of medicine and microbiology.

"The question isn't whether these things occur at all — it's whether they occur disproportionate to what you would expect in a population that wasn't vaccinated."

To get a true sense of the risk, researchers should study various groups of people — of the same age and ethnicity, and with the same underlying health issues — who each took a different vaccine, to see potential side effects, he said.

Statistically, there is a greater risk of Manitobans dying from COVID-19 than for blood clots to form after receiving a dose of the AstraZeneca-Oxford vaccine, notes Dr. Anand Kumar. (John Woods/The Canadian Press)

In terms of Manitoba's overall vaccination effort, Kumar believes the pause should only be in effect if it doesn't hamper how many shots are injected into arms, because the risk of contracting COVID-19 is still greater than blood clotting, assuming the data holds true.

Statistically, there is a greater risk of Manitobans dying from COVID-19 than for blood clots to form after receiving a dose of the AstraZeneca-Oxford vaccine, he said.

University of Saskatchewan pharmacy professor Ekaterina Dadachova also notes that there is increased risk of blood clots for everyday products. Some birth controls, for example, warn that women over the age of 35, who are heavy smokers, are more at risk of blood clots.

'This is puzzling to me'

Manitoba Chief Provincial Public Health Officer Dr. Brent Roussin received his first dose of the AstraZeneca-Oxford vaccine on March 19, partially to build public trust in the immunization.

But after Monday's announcement, Manitoba resident Kathy Kwasnik, 44, doesn't know what to believe.

"Is it safe? Is it not safe?" said Kwasnik.

"This is puzzling to me."

Lauralee McDougall, 51, received her first dose of the AstraZeneca-Oxford vaccine March 18. She is pro-vaccine and generally follows the advice of health professionals, but her confidence in the immunization is now shaken, to the point that she advised her husband to wait until he's eligible for the Pfizer-BioNTech or Moderna vaccines.

"If so little is known about [the AstraZeneca-Oxford vaccine], why was that the chosen one for people who are already at such high risk for serious effects of Covid?" McDougall said.

While she believes health professionals are working with the knowledge available, McDougall wonders "if maybe more time was needed before they started rolling that particular [vaccine] out."

But McDougall is also just one of many Manitobans who are now in limbo. They have received their first dose of the AstraZeneca-Oxford vaccine, but they are also part of the demographic impacted by the pause.

She now wonders how Monday's announcement impacts her second dose, and whether she can get a dose of a different vaccine instead.

If a person is at greater risk of contracting COVID-19 and would have to wait significantly longer for other approved vaccines, then they should get the AstraZeneca-Oxford vaccine, said Dadachova, whose expertise is treating infectious diseases.

She advises against mixing-and-matching, because the vaccines weren't designed for that. Instead, people who have questions or concerns should consult their physician.

"I would not encourage people to make such important decisions by themselves. They should talk to their doctor," she said.

Blood clots may trigger symptoms similar to those of a stroke or heart attack. Should someone start experiencing such symptoms, they should seek medical attention, said Baillie of Doctors Manitoba.


Nicholas Frew is an online reporter with CBC Edmonton. Hailing from Newfoundland, Frew moved to Halifax to attend journalism school. He has worked for CBC newsrooms in Manitoba and Saskatchewan. Prior to joining the CBC, he interned at the Winnipeg Free Press.

With files from Peggy Lam and Erin Brohman


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