OTTAWA -- Canada’s chief public health officer says the various health entities guiding the science on vaccine use in Canada are working collaboratively, despite differences in the recommended use of the AstraZeneca vaccine.
Dr. Theresa Tam said on Tuesday that Health Canada, the Public Health Agency of Canada and the National Advisory Committee on Immunization (NACI) work in “lockstep,” after NACI announced on Monday it was advising a pause in the use of the drug for those under the age of 55 due to the rare possibility of blood clots.
Health Canada subsequently stated that it is continuously monitoring the situation and will be working with international manufacturers to require a “detailed assessment of the benefits and risks of the vaccine by age and sex in the Canadian context.”
On March 24, Health Canada updated AstraZeneca’s product label to provide detail on reports of blood clots associated with low levels of blood platelets following immunization.
However, their guidance on the use of AstraZeneca remains the same – that for those over the age of 18, the benefits outweigh the risks and that the drug itself has “not been associated in the overall risk of thrombosis.”
Canada has already administered around 300,000 doses of the drug, with no reports of adverse side effects. Cases of blood clots in Europe have been reported mainly in younger women.
Tam said NACI looked at the information coming in from overseas and took a “precautionary approach,” adding that Monday’s update had to be done quickly.
All provinces and territories have since adjusted their guidance following the announcement.
Asked whether this change in recommendation adds to vaccine hesitancy, Tam said it’s important to understand the science on COVID-19 vaccines is rapidly changing which means the guidelines do too, but Canada’s review process remains “vigorous.”
“The advice on any medication or vaccine can evolve over time and I think Canadians should be reassured that we have systems in place to detect safety signals and then analyze them,” she said. “It’s actually been a quite remarkable feat of international collaboration and science to try and sort out the initial reports.”
Deputy Chief Public Health Officer Dr. Howard Njoo said he acknowledges the changes could lead to heightened confusion.
“Certainly we understand that for the average Canadian there are obviously I think a lot of questions and concerns,” he said Tuesday. “At the end of the day, what’s really important is key is it’s good communication and being transparent and open and that’s what I think is important moving forward.”
The NACI has previously recommended suspending the use of AstraZeneca in those over the age of 65 years, citing efficacy concerns, but then reversed their position weeks later, with access to new information.
In an interview on CTV News Channel’s Power Play on Tuesday, NACI chair Dr. Caroline Quach said she hopes Canada will receive the necessary data from the supplier within “two to three weeks” to make a firm recommendation about the vaccine’s use in those under the age of 55.
“At which point in time we’ll have to position ourselves again to see if this pause is long-term or a temporary pause,” she said, reinforcing that transparency is the best policy in the vaccine journey.
“Are you going to tell us that being too transparent leads to hesitancy? I sure hope not. But you know when we see something we tell people exactly what we see and why we take that decision. I understand that it may not make everyone happy,” she said.
