COVID-19 Booster Doses

Protection after a primary COVID-19 vaccine series decreases over time, especially against the Omicron variant of concern. COVID-19 vaccine booster doses help to increase protection against symptomatic infection and severe outcomes at the individual level and helps to reduce transmission at the population level.

Get Vaccinated and Stay Up to Date

Up to date means a person has received all recommended COVID-19 vaccine doses, including any booster dose(s) when eligible.

Booster Doses Eligibility

Trying to figure out if you are eligible for a COVID-19 booster dose? We can help.

Booster Doses Information

We answer your frequently asked questions about COVID-19 booster doses.

Bivalent COVID-19 Booster Dose

Starting Tuesday, October 18^th to individuals aged 12 and over will be eligible for the Pfizer COVID-19 bivalent vaccine. The eligibility for the Moderna COVID-19 bivalent vaccine remains 18 and over.

Appointments are strongly recommended and can be booked online (www.GetYourShotCK.ca) or by calling 519-351-1010.
The flu shot and the COVID-19 vaccine can be administered at the same time, or before or after each other for individuals aged 5 years and older.
Children younger than 5 years of age are recommended to wait 14 days between receiving the flu shot and the COVID-19 vaccine.

Both the Pfizer and Moderna bivalent vaccines will be available at the CK Public Health vaccination clinics that are administering vaccine to those aged 12 and over (www.CKPublicHealth.com/clinics) *Individuals must be 18 or over to receive the Modern bivalent vaccine.
When booking your COVID-19 bivalent vaccine appointment, simply register for the timeslot that works best for you, and you can choose which vaccine you would like once you arrive to the clinic (Both Pfizer and Moderna will be available at the clinics, though individuals must be 18 years of age to receive the Moderna bivalent vaccine)
It’s recommended that individuals receive their booster dose six months after completing their primary COVID-19 vaccination series or after receiving their most recent booster. However, booster doses may also be administered as early as three months after an individual received their most recent dose of vaccine.
Individuals who are at higher risk of severe outcomes, including individuals aged 65 and older, are recommended to receive booster doses at an interval of three months.
Individuals who have had COVID-19 should wait a minimum of three months before receiving a booster dose of the bivalent vaccine.

For a complete list of COVID-19 vaccination clinics, including locations, dates and times, visit www.CKPublicHealth.com/clinics

4th Dose Eligibility

3rd Dose Eligibility

Individuals with Immune Compromising Health Conditions

Moderately to severely immunocompromised individuals who are eligible for a three-dose primary series are recommended to receive booster doses after their third dose at the following intervals:

1st Booster Dose (i.e. 4th dose)

(if 5-11) not eligible
(if 12-17) 6 months after 3rd dose
(if 18+) 5 months after 3rd dose

NEW: 2nd Booster Dose (i.e. 5th dose)

(if 5-17) not eligible
(if 18+) 5 months after first booster

A three dose primary series of mRNA COVID-19 vaccine is recommended for the below populations eligible for vaccination with the vaccine product authorized for their age group (these recommendations also apply to children aged 5-11 who fall within any of the categories below).

The third dose should be administered 8 weeks (56 days) after the second dose.

Individuals receiving dialysis (hemodialysis or peritoneal dialysis)
Individuals receiving active treatment1 (e.g., chemotherapy, targeted therapies, immunotherapy) for solid tumour or hematologic malignancies
Recipients of solid-organ transplant and taking immunosuppressive therapy
Recipients of chimeric antigen receptor (CAR)-T-cell therapy or hematopoietic stem cell transplant (within 2 years of transplantation or taking immunosuppression therapy)
Individuals with moderate to severe primary immunodeficiency (e.g., DiGeorge syndrome, Wiskott-Aldrich syndrome)
Individuals with stage 3 or advanced untreated HIV infection and those with acquired immunodeficiency syndrome
Individuals receiving active treatment with the following categories of immunosuppressive therapies: anti-B cell therapies2 (monoclonal antibodies targeting CD19, CD20 and CD22), high-dose systemic corticosteroids (refer to the Canadian Immunization Guide for suggested definition of high dose steroids), alkylating agents, antimetabolites, or tumor-necrosis factor (TNF) inhibitors and other biologic agents that are significantly immunosuppressive

When should you get a booster after testing positive for COVID-19?

Individuals 12 years of age and older, infected* with COVID-19 after their primary series but before their booster dose, are recommended to receive their booster dose 3 months after symptom onset or positive test (if asymptomatic) and, for 12 to
17 years olds, provided it is at least 6 months from completing the primary series. As per NACI, emerging evidence indicates that a longer interval between SARS-CoV-2 infection and vaccination is associated with improved antibody responses to COVID-19 vaccines. With informed consent, individuals may receive a booster dose once they are asymptomatic and have completed their isolation.
*A previous infection with SARS-CoV-2 is defined as a COVID-19 case confirmed by a molecular (e.g., PCR) or rapid antigen test, or symptomatic AND a household contact of a confirmed COVID-19 case.

Can people have a different brand for their booster?

If someone aged 18 to 24 yrs old had two doses of Moderna, should the individual receive Pfizer or Moderna for their third dose?

Can individuals who have a mixed series of viral vector and mRNA vaccines receive a booster dose?

Getting Your Booster Dose

Getting your booster dose is easy. Visit our COVID-19 Vaccine Clinics page to find the best option for you.