No wrong choice for second dose of COVID vaccine: Regina doctor

Saskatchewan residents now have a choice on which vaccine to get for their second dose of the COVID-19 vaccine.

The province announced Tuesday that it will be following the latest guidelines on mixing and matching vaccines from the National Advisory Committee on Immunization (NACI).

Dr. Alex Wong, an infectious disease physician in Regina, told the Greg Morgan Morning Show that there’s no wrong choice.

However, Wong does have a preference for those who got AstraZeneca for their first dose.

“I think my stated preference for most people in Saskatchewan is probably that they wait for the second dose of Pfizer. Actually, there’s no waiting involved because people were getting Pfizer as a second dose in the drive-thru (Tuesday) night in Regina so I know it’s immediately available,” said Wong.

Wong said people who got AstraZeneca as a first dose absolutely did the right thing. He explained we needed to get doses into arms as fast as possible to reduce hospitalizations and deaths when the province was “crashing and burning.”

A lot has changed since then as case numbers, hospitalizations and test positivity have dropped. Wong said there is no longer the same degree of urgency as there was a few months ago.

Wong explained why he prefers going with an mRNA vaccine like Pfizer for a second dose. While the risk of blood clots with AstraZeneca is still very low, he said it’s still there.

“The risk of blood clots is more clearly understood now in VITT with AstraZeneca and there isn’t that same risk with Pfizer,” said Wong.

Another reason Wong prefers Pfizer as a second dose is because supply is not an issue, as that vaccine makes up the majority of doses arriving in Saskatchewan into July.

Wong also pointed to a study in Spain that suggests getting an mRNA vaccine like Pfizer for a second dose after a first dose of AstraZeneca actually provides a greater antibody response.

Wong said two doses of AstraZeneca also provides superb protection against severe illness, hospitalization and death against all variants.

Regardless of what choice is made, Wong said people should get their second dose right away.