OTTAWA -- Addressing the reactions from frustrated medical professionals who have voiced concerns over an influential national panel of immunization experts’ most recent COVID-19 vaccine advice to Canadians, Prime Minister Justin Trudeau sought to make the federal government’s position clear on Tuesday: every vaccine authorized is safe.

“All vaccines in Canada have been approved by Health Canada. Our advice to provinces and territories, and to Canadians, has not changed,” Trudeau said during his national address. “Get your shot as soon as it’s your turn.”

This is in light of The National Advisory Committee on Immunization (NACI) being accused of contributing to confusion and doubt about COVID-19 vaccines after doubling down on its position that mRNA vaccines are “preferred” over viral vector doses, and that Canadians should weigh the risks before they decide which one to receive.

Right now NACI isn’t even recommending people under the age of 30 receive a viral vector shot, but ultimately that’s a decision for provinces to make as part of their respective vaccine rollouts.

It has also suggested that people who are concerned about the rare risk of blood clots associated with the AstraZeneca and Johnson & Johnson shots could opt to “wait” until they can receive a Pfizer or Moderna vaccine.

Trudeau faced further questions about the ongoing incongruity between what Health Canada’s position on the four COVID-19 vaccines the agency has authorized for use — that they are all safe, effective and can be offered to any adult — and the constantly moving goalposts of who NACI thinks the shots should be given to.

In response, Trudeau said that the federal government's priority is making sure everyone who wants it, can receive their shot as soon as they are eligible. "It is a good thing that we get to hear from a broad range of medical experts and doctors making recommendations to keep us safe. The bottom line is we need to, all of us, get vaccinated as quickly as possible so we can get back to normal,” he said.

Chief Public Health Officer Dr. Theresa Tam also weighed in on Tuesday, saying that Canadians should be confident in receiving any Health Canada-cleared vaccine because they are all shown to be effective. However, she said, people can and should still make their own individual decision based on their personal risk calculation.

“I think it is hard for people to understand evolving science and evolving data. That's what's been so difficult for so many people throughout this pandemic,” she said, adding that NACI offering rolling guidance on the latest evidence on efficacy and risks of potential adverse effects is important to help ensure Canadians can make informed decisions about vaccination.

The volunteer panel NACI is arms-length from the federal government but reports to the Public Health Agency of Canada. As it has been designed, NACI provides guidance on how new vaccines should be used in Canada. The body has been in existence since 1964, but since the onset of the pandemic, it has been predominately focused on COVID-19 vaccines.

MOST DOSES COMING ARE MRNA

With millions of doses of mRNA vaccines slated to land each week going forward and no solid confirmation of next shipments of AstraZeneca or Johnson & Johnson, the suggestion that people will be able to receive a viral vector shot before being offered an mRNA vaccine may not play out in reality.

As Procurement Minister Anita Anand highlighted Tuesday, Canada will be receiving up to 36 million doses of mRNA vaccines over the next two months, the majority of which will be Pfizer shots, though the government has gone to pick up the next shipment of Moderna a week early and will be arriving on Wednesday.

In contrast, while Anand said there are another 1.6 million doses of AstraZeneca set to arrive before the end of June, pending ongoing negotiations with the U.S. for more, there are no future Johnson & Johsnon deliveries planned after Health Canada held up the first batch of 300,000 for further safety review.

“The majority of the doses… are from mRNA vaccine producers, being Pfizer and Moderna. This month alone we are expecting at least 9 million doses of those suppliers. Overall, we have procured 44 million doses of Moderna and 48 million doses of Pfizer,” Anand said, going on to note the government continues to press for confirmation of coming viral vector vaccine shipments from AstraZeneca and Johnson & Johnson.

'A TRAGEDY OF MIXED MESSAGING'

NACI’s suggestions are contrary to the widespread messaging from various levels of government and public health officials to get the first vaccine offered to you, and NACI’s guidance has been condemned as being “extremely damaging.”

“The message that came out of that statement yesterday was that there were clearly two tiers of vaccine, an elite mRNA class of vaccine, and then vector vaccines that are probably not necessarily very safe. And that obviously has eroded a great deal of trust that was already quite deepened to begin with,” said CTV News Infectious Disease Specialist Dr. Abdu Sharkawy on CTV News Channel. “This is problematic.”

Sharkawy said that there are other positives to AstraZeneca that are not being pointed out, such as its efficacy against the B.1.1.7 variant of concern, it is more easily distributed, and has shown to hold efficacy with a longer dose interval.

“I have colleagues who have witnessed several of their own patients in the ICU between the ages of 30 and 50, who were offered the AstraZeneca vaccine. They could have been protected. They've ended up on ventilators. That's a tragedy of poor communication, it’s a tragedy of mixed messaging,” he said.

After federal Health Minister Patty Hajdu dodged questions about which advice Canadians should be listening to on Monday, suggesting speaking with their doctors about which vaccine to take, Conservative MP and health critic Michelle Rempel Garner called on the federal government to step in.

“What Canadians need is clear, concise, and constant communications when it comes to vaccine use. Conservatives have been calling for this for weeks. The buck stops with the health minister. She must immediately fix this problem of her creation. Lives are at stake,” she said in a statement ahead of Trudeau’s address.

PM GLAD HE GOT ASTRAZENECA

Trudeau was among the cohort of Canadians who were recently offered and received the AstraZeneca vaccine. Asked what he would say to the approximately 1.7 million Canadians who have taken this vaccine, but are now hearing from certain medical voices that they are considered less preferable, Trudeau said he’s “very happy” he got his shot.

“I am extremely pleased that I got the AstraZeneca vaccine a number of weeks ago. It was extremely important to me to be able to protect my loved ones, to protect my family, and to do my part to ensure that all Canadians get through this.

“The impacts of catching COVID are far greater and far deadlier as we've seen across the country, than potential side effects which, although serious, are rare,” Trudeau added.

The viral vector-based AstraZeneca and Johnson & Johnson doses have been linked to an extremely rare and potentially life-threatening blood-clotting syndrome called vaccine-induced immune thrombotic thrombocytopenia (VIITT). The risk for developing this syndrome is estimated to be anywhere from one case in 100,000 doses to one case in 250,000.

When asked what her advice would be to Canadians who may be wondering whether to complete the full double dose vaccination with two shots of the AstraZeneca vaccine—pending the arrival of more doses—or whether they should be looking to mix vaccines and receive a second shot of an mRNA vaccine, she said it’s something currently being assessed by NACI and federal officials will have more to say before it’s time for those people to receive their second shots.

“Watch this space,” said Tam.

WHY NACI'S MESSAGE DIFFERS

NACI’s latest guidance is not the first time the panel has issued advice that’s sparked confusion. Past instances have been attributed to NACI’s work being intended to “complement, not mirror” the official Health Canada authorizations.

“As the regulator, Health Canada authorizes each vaccine for use in Canada according to factors based on clinical trial evidence, whereas NACI bases its guidance on the available and evolving evidence in a real-world context, including the availability of other vaccines,” Deputy Chief Public Health Officer Dr. Hoawrd Njoo said in early March.

Asked Monday on CTV News Channel’s Power Play whether she thought NACI’s guidance was contributing to vaccine hesitancy, NACI chair Dr. Caroline Quach-Thanh—whose term is up in June— said she didn’t think so, and that the intent was to help people make a decision on which vaccine to get based on their risk of contracting COVID-19. 

“If, for instance, my sister was to get the AstraZeneca vaccine and die of a thrombosis when I know that it could have been prevented and she’s not in a high-risk area, I’m not sure I could live with it,” she said.

She’s previously suggested that part of the reason what Canadians are hearing from NACI is different than what Health Canada has said is because as an independent panel it includes infectious diseases, immunology, pharmacy, epidemiology, and public health experts who are “on the ground.”

“If you're only sitting in your ivory tower, it's harder then, to relate to what's actually happening,” she said in an interview on CTV’s Question Period in March.

With files from CTV News’ Jackie Dunham.