Ontario is pausing the rollout of the AstraZeneca COVID-19 vaccine in response to concerns about incidents of blood clots linked to it.
Ontario’s chief medical officer of health, Dr. David Williams, made the announcement today shortly after 4 p.m. accompanied by Dr. Dirk Huyer, coordinator of the provincial outbreak response, and Dr. Jessica Hopkins, chief health protection and emergency preparedness officer at Public Health Ontario.
“The important thing to keep in mind is how the vaccine safety system is really working in Ontario and Canada and that allowed us to recognize this safety signal.”
The COVID-19 advisory science table for Ontario released a report today on VITT following the two adenovirus vector COVID-19 vaccines (AstraZeneca and COVISHIELD) comparing the incidence rates of several countries with Canada’s rates.
The report estimates the VITT rate from AstraZeneca and COVISHIELD in Canada is about one per 100,000 doses. Both Williams and Hopkins said the decision was also partly influenced by the change in the COVID situation in Ontario.
“The decision to pause is also based on the increased and reliable supply of the Pfizer and MOderna vaccines and also the recent downward trend in cases,” said Williams.