COVID-19 vaccine dosing intervals, booking and PPE reminders

Advisory Alert

April 14, 2021

*Cette information est seulement disponible en anglais.

To: Local Health System Partners


This Advisory Alert provides an overview of exceptions to the extended second dose intervals for COVID-19 vaccination, the processes for re-booking second dose appointments, and personal protective equipment reminders.

Exceptions to extended COVID-19 vaccine dosing intervals

On March 26, 2021, the provincial Vaccine Clinical Advisory Group (VCAG) Recommendations of Exceptions to Extended Dose Intervals for COVID-19 vaccines, released its findings which are summarized here.

Special populations were reviewed under the following categories: 1) pregnancy, 2) immunocompromising conditions and immunosuppressive therapies, and 3) age. No changes were made to the recommended dosing schedule of 16 weeks for pregnant individuals or those of advanced age, as it was determined that the four-month dosing interval remains appropriate in the context of constrained vaccine supply.

Exceptions to the extended dose intervals were recommended. These exceptions include transplant recipients as well as individuals with malignant hematologic disorders and non-hematologic malignant solid tumours receiving active treatment (chemotherapy, targeted therapies, immunotherapy), excluding individuals receiving solely hormonal therapy or radiation therapy. These populations should receive COVID-19 vaccines at the dose interval as indicated in the product monograph. This means that the second dose of the Pfizer-BioNTech, Moderna or AstraZeneca COVID-19 vaccine should be provided at an interval of 21 days, 28 days, or 12 weeks respectively. The National Advisory Committee for Immunization continues to review evidence which informs the provincial VCAG recommendations.

Scheduling second dose appointments

Scheduling of dose intervals is determined at the time of immunization based on factors such as eligibility as described above and based on the type of vaccine administered. All necessary information is tracked in the COVax booking system and a second dose is scheduled as appropriate.

Individuals who already received first dose

Individuals who have already received a first dose of a COVID-19 vaccine and meet the newly identified criteria to receive a second dose as per the product monograph can self-identify by calling the booking centre at 705.674.2299 (toll-free: 1.800.708.2505) OR 1-844-782-2273. Additionally and as capacity allows, primary health care providers are asked to advise any patients who have received their first dose and who are eligible for their second dose at the product monograph timeline. Primary care providers should advise these patients to call the booking centre to rebook their second dose appointments at the shortened timeline.

All those who call the booking centre and self-identify will be screened per Ministry guidelines at time of booking and must attest to their eligibility for a shortened dose interval. If eligibility is confirmed, the second dose will be booked per product monograph. At time of immunization, individuals who self-identify will be assessed again to determine if they are eligible for their second dose based on the product monograph schedule. If at that time, it is determined that further medical consultation is required, immunization will not occur.

To ensure no eligible individuals are missed in the process, Public Health Sudbury & Districts will soon issue public communication regarding the eligibility criteria for the shortened dose interval.

Individuals with upcoming first dose appointments

All individuals who have not yet received their first dose, are asked to identify their eligibility for the product monograph timeline at the time of their vaccination appointment. Eligibility will be evaluated per Ministry guidance and immunizers will conduct an assessment of vaccination second dose interval. Those who are confirmed eligible for the shorter second dose timeline, will be re-booked at the product monograph interval prior to leaving the immunization center. This process will take effect in the coming days.

As a reminder, in addition to transplant recipients and individuals undergoing active treatment, other groups immunized according to the product monograph include residents of long-term care homes, retirement homes and assisted living facilities identified by the Ontario Ministry of Health, as well as individuals who live on reserve in First Nation communities.

PPE reminders at time of immunization

As many of our primary care partners and pharmacy settings continue to support local vaccination efforts at mass clinics or plan for immunization clinics in practice settings or pharmacies, it is important to remember that in addition to medical masks, eye protection must be worn when providing immunizations. Additionally, prior to immunization, a risk assessment and screen for COVID symptoms must be conducted. For more information, please review Public Health Ontario’s guidance for immunization.

Additional information

Due to the ever-changing nature of information on the COVID-19 vaccines, it is encouraged that you bookmark the COVID-19 vaccine resource centre and check back regularly.

For additional information on the COVID-19 vaccines, as well as for specifics on how it is being rolled out locally, please visit Public Health’s COVID-19 vaccine webpage.


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 April 14, 2021