Ahmed Waiting for Provincial Direction on Vaccine Interchangeability


The Medical Officer of Health for Windsor-Essex is waiting for more information on the interchangeability of COVID-19 vaccines.

On Tuesday, the National Advisory Committee on Immunization (NACI) says Canadians who received the Oxford-AstraZeneca shot as their first dose of COVID-19 vaccine can safely be offered either Pfizer-BioNTech or Moderna for their second jab.

Because of the recommendation, Dr. Ahmed says if someone isn't comfortable receiving AstraZeneca as their second dose, he is more confident in recommending mixing vaccines.

"People who have received AstraZeneca vaccine as their first dose, they now have the option to chose for an mRNA vaccine once a provincial direction is made," he says. "For those who have received the mRNA COVID-19 vaccine, which includes Pfizer of Moderna, they can get a different vaccine but preferentially our recommendation is they should get the same vaccine as their second dose to make sure they complete their series with the same vaccine," says Dr. Ahmed.

If you received AstraZeneca as your first dose and choose to have Pfizer or Moderna as your second dose, Dr. Ahmed warns of more intense side effects.

"We are not talking about the severity of the disease, we are not talking about any type of severe, adverse reaction," he says, "These are all the local reactions that is a more pronounced local reaction to the vaccine that happens all the time, such as redness, swelling, pain or fever, some of those common reactions, so please know that that would be a possibility."

Canada's chief public health officer Dr. Theresa Tam said on Tuesday the decision to mix and match vaccines is entirely driven by the risk of the extremely rare side-effect linked to AstraZeneca known as V-I-T-T. Forty-one Canadians have now had a confirmed or suspected case of V-I-T-T and five have died.

Canada joins Denmark, Finland, France, Germany, Sweden, Norway and Spain among countries mixing and matching vaccines. 


— With files from The Canadian Press