Toronto-A new breakthrough has been made on the road to mass vaccination against COVID-19 in Canada.

Ontario, Alberta and Saskatchewan announced on Tuesday that they will no longer receive the first dose of AstraZeneca vaccine. Reasons for this sudden change include claims of uncertain supply and concerns about the rare risk of vaccine clots.

However, authorities in other provinces have stated that they do not intend to suspend AstraZeneca’s vaccination, and federal health officials have stated that they still believe that the vaccine is safe to use in most people.

To help Canadians understand what the scientific community thinks of AstraZeneca’s vaccines, CTV’s chief news anchor and senior editor Lisa LaFlamme and Menaka Pai of McMaster University in Hamilton, Ontario Dr. Yi had a conversation. Pai is an associate professor of hematology and thromboembolism (in other words, a clot specialist) and a member of the Ontario COVID-19 scientific consultation form.

The following is a transcript of the interview, edited for length and clarity.

Lisa LaFlamme: Doctor, you are at the Ontario Science Help Desk, so your job is to look at science. What triggered today’s sudden announcement?

Dr. Peanut Butter: Okay, this is science, Lisa. It is changing very fast. In many parts of the country, the reality of the pandemic is also changing. I think this is a deliberate decision based on evolving science.

flame: Okay, so why is AstraZeneca so successful in the UK and so full of problems in this country?

father: I think AstraZeneca is still a very effective vaccine against COVID-19. It reduces deaths, hospitalizations and serious illnesses, which is what we have seen in the UK. In Canada, the situation is different. We certainly know more about these adverse events, we are looking for them, and we have benefited from the benefits of more vaccine options in the past few weeks.

flame: Therefore, this is an option-we are fortunate enough to pause it at the first dose. But what about the second dose? Anyone who buys AstraZeneca now feels a bit like a guinea pig or even a yo-yo. With so many different opinions, what should someone do for their second dose?

father: First of all, I want to sympathize. Many people I love are taking it for the first time and feel worried. For the second dose, we are waiting for more science, so we hope that a study in the UK shows that mixing and matching doses are safe and effective. We also believe that the risk of these blood clots may be slightly lower after the second dose, and with the development of science, we will focus on this and make good suggestions to help Canadians feel relieved.

flame: Doctor, every word of us is on our lips. Thank you so much for your insights tonight.

father: Thank you, Lisa.