TORONTO -- Ontario will no longer offer first doses of the AstraZeneca COVID-19 vaccine due to an increase in reports of rare blood clots.
The announcement was made by Ontario’s Chief Medical Officer of Health Dr. David Williams on Tuesday afternoon.
“This decision was made out of an abundance of caution,” Williams said.
“It is not that the risk for individuals has gone up extensively at this time but because it is sometimes severe we want to be cautious and say ‘let's pause it’ while we look at the data and information."
The AstraZeneca vaccine was being offered to individuals aged 40 and up at numerous pharmacies across the province.
According to Chief Health Protection and Emergency Preparedness Officer Dr. Jessica Hopkins, the risk of vaccine-induced thrombotic thrombocytopenia (VITT) associated with the vaccine in Ontario is one in 60,000.
Hopkins later clarified that as of May 8, eight Ontarians have developed blood clots related to the vaccine.
“At this point in time, and given that we're seeing the overall case numbers of COVID going down, and an increase in the safety signal at a population level, it makes sense to pause AstraZeneca, because the risk of severe outcomes with VITT shouldn't be underestimated.”
At the same time, officials say that the AstraZeneca vaccine does provide significant protection from serious illness, hospitalization and death related to COVID-19.
“We maintain that those who received their first dose with the AstraZeneca vaccine did absolutely the right thing to prevent illness, and to protect their families, loved ones, and communities,” Williams said, adding that Tuesday's announcement was the result of a "safety signal" flagged to health officials.
Select pharmacies in the Greater Toronto and Hamilton Area, as well as Ottawa and Windsor-Essex, have started to receive doses of the Pfizer-BioNTech and Moderna vaccines.
Williams added that the decision to pause is also based on the increased and reliable supply of these other vaccine options.
The remaining supply of AstraZeneca in Ontario will be reserved for second doses. Officials said that data from the United Kingdom shows there is a much lesser risk of VIIT following the second shot of the vaccine.
The province is waiting for more data before making any further announcements on second doses of AstraZeneca or whether the vaccine can be paired with a different COVID-19 shot.
Infectious disease expert Dr. Abdu Sharkwy told CP24 Tuesday night that those who received a dose of AstraZeneca vaccine made the correct decision.
“I think it's still important to remember that if you've gotten the shot and you got it during a period where community transmission was high, you've probably saved your life if not countless other lives,” he said. “There's plenty of ICUs that were full of young people who had the option of taking the AstraZeneca vaccine and didn't take it.
Sharkawy added that Tuesday’s announcement is not “mixed messaging,” but rather the government adapting to the latest data and information.
I think it is responsible adaptation to what's going on within your community and what your risk exposure is and it's gonna take some time for people to wrap their heads around that because the messaging hasn't been perfect, but we have to start somewhere.”
Bioethicist Kerry Bowman, on the other hand, argued that messaging around the AstraZeneca vaccine has been “absolute confusion” and this could result in mistrust on the part of the public.
“I appreciate the nuanced arguments that everybody's putting forward but that's asking an awful lot of a lot of people that are looking for some very clear direction,” he said. “We've really wobbled back and forth and we're gonna pay quite a price for it on this front of vaccine hesitancy.”
Canada's National Advisory Committee On Immunizations (NACI) has been criticized for labelling the Pfizer-BioNTech and Moderna vaccines as the “preferred” choice over AstraZeneca and the Johnson & Johnson options. The statement came after months of NACI urging Canadians to get the first shot available to them.
