Ontario pauses administering first doses of AstraZeneca vaccine

Ontario reported 2,320 cases of COVID-19 on Wednesday (an 11.9% increase from the 2,073 cases reported the day before) and 32 more deaths (a 113.3% increase from the 15 reported the prior day). The new numbers include 712 cases in Toronto, 452 in Peel, 157 in York Region, 139 in Durham and 113 in Hamilton.

The province has seen a major decline in cases since the Ontario government declared a province-wide state of emergency with a stay-at-home order in early April to stem increasing hospitalization numbers. The order is set to end on May 20; however, numerous reports suggest it will likely be extended for another two weeks, until June 2.

On Monday, Health Minister Christine Elliott indicated that the province is looking to see a significant drop in cases/ICU admissions before lifting the order.

“It’s really a question of time and how quickly those numbers can come down,” Elliott said at a press conference on Monday. “We are not at the place where we can release the stay-at-home order, but there will be a plan when that time does come.”

Dr. David Williams, chief medical officer of health, said on Monday that he would like to see daily COVID-19 cases drop below 1,000 before easing restrictions.

“Slow and steady and stay open. That’s our goal,” Dr. Williams said, noting that they do not want the province to experience a fourth wave of the virus.

Over 50% of Ontarian adults have received at least one dose of a vaccine. As of Wednesday morning, 6,491,666 doses of the COVID-19 vaccine have been administered out of a total of 7,832,125 doses delivered to the province for administration, meaning 82.9% of doses delivered to Ontario have been administered.

Effective Tuesday, May 11, however, Ontario announced it was pausing the rollout and administration of first doses of the AstraZeneca vaccine—a decision that was made, according to Dr. Williams, “out of an abundance of caution” due to an observed increase in the rare blood clotting condition, vaccine-induced immune thrombotic thrombocytopenia (VITT), linked to the AstraZeneca vaccine.

“In collaboration with health experts at Public Health Ontario, the Science Advisory Table and our federal, provincial and territorial partners, we are reviewing the data to consider options for the use of the AstraZeneca vaccine for second doses and more broadly moving forward,” Dr. Williams said in a statement on Tuesday.

As of May 8, 651,012 doses of the AstraZeneca vaccine were administered with a VITT rate of 0.9 per 100,000 doses administered. 202,873 doses of the COVISHIELD vaccine were administered with a rate of VITT of 1 per 100,000 doses administered. However, according to provincial health officials, in the days leading up to the province’s decision to pause the AZ vaccine, there have been increased reports of VITT, with a rate of 1.7 per 100,000 doses administered.

Dr. Williams noted that the decision to pause is also based on the “increased and reliable supply” of the Pfizer and Moderna mRNA vaccines and the downward trend in cases.

Still, there has been some confusion about what happens to those who already received their first dose of the AZ vaccine.

Dr. Williams noted that they are seeing “early promising results” of administering two doses of different vaccines and have asked the National Advisory Committee on Immunization (NACI) to provide direction on the interchangeability of COVID-19 vaccines.

“Based on the much higher risks of COVID-19 infection recently observed in Ontario including hospitalization, serious illness and death, 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.

Click here for more COVID-19 Ontario updates.

Article exclusive to TRNTO