Ontario pauses rollout and administration of AstraZeneca’s COVID-19 vaccine

May 11, 2020

*Cette information est seulement disponible en anglais.

To: Local Health System Partners


Effective today, administration of AstraZeneca is on pause

As of May 11, 2021, the province of Ontario has paused the rollout and administration of first doses of the AstraZeneca COVID-19 due to an observed increase in the rare blood clotting condition known as vaccine-induced immune thrombotic thrombocytopenia (VITT).  This decision was also based on the increasing mRNA vaccine supply and decreasing rates of COVID-19.

In collaboration with health experts at Public Health Ontario, the Science Advisory Table and federal, provincial, and territorial partners, the provincial government is reviewing the data to consider options for the use of the AstraZeneca vaccine for second doses and more broadly moving forward.

Early studies have shown promising results with the administration of two doses of different vaccines and the province is seeking guidance from the National Advisory Committee on Immunization (NACI) on the interchangeability of COVID-19 vaccines moving forward.

Based on the much higher risks of COVID-19 infection and with the variants of concern stronger and more transmissible, those who received their first dose of the AstraZeneca vaccine did the right thing to prevent severe illness and to protect their communities.  Additional details on second dose recommendations will be shared following further evaluation.

Within the Public Health Sudbury & Districts service area, 459 doses of AstraZeneca have been administered by primary care and 2801 doses by local pharmacies.

All eligible individuals, who are net yet immunized, are encouraged to book an appointment to receive an mRNA COVID-19 vaccine when it is available to them.

For further details, read Ontario’s statement on pausing the administration of the AstraZeneca vaccine.


Original Signed By

Dr. Penny Sutcliffe
Medical Officer of Health and Chief Executive Officer

NOTE: All Advisory Alerts are found on our website.

This item was last modified on May 11, 2021