Skip to main content Skip to Navigation Skip to Footer

Third Doses of COVID-19 Vaccines

Two-doses of a COVID-19 vaccine provides strong protection against COVID-19 infection and severe outcomes, including against the Delta variant, for most people.

As an additional measure to continue protecting the most vulnerable, third doses of the COVID-19 vaccine will be offered to those at highest-risk, providing them with an extra layer of protection against the Delta variant. 

These populations include those who are moderately to severely immunocompromised and vulnerable elderly in high-risk congregate settings.

Moderately to Severely Immunocompromised


  • Individuals receiving active1 treatment (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 therapies (monoclonal antibodies targeting CD19, CD20 and CD22), high-dose systemic corticosteroids, alkylating agents, antimetabolites, or tumor-necrosis factor (TNF) inhibitors and other biologic agents that are significantly immunosuppressive.

Individuals in the above groups can receive a third dose one or two months after their second dose.  If you fit into one of these groups, contact your primary care provider to determine when to get your third dose to get the best immune response.

Referral Forms
If you don’t have a primary care provider, call the Porcupine Health Unit at 705-360-4319 or 1-800-461-1818. 

Vulnerable Elderly in High-Risk Congregate Settings

The immune response in residents who live in long-term care homes is lower than the general population. A third dose of a COVID-19 vaccine will be offered to residents of high-risk congregate settings including long-term care homes, higher-risk licensed retirement homes and First Nations elder care lodges.

Individuals in these settings can be receive a third dose five months after their second dose.

The Porcupine Health Unit is currently working with long-term care homes, high-risk retirement homes (as identified by the province) and elder care providers to plan vaccine clinics for their residents.

If eligible, you will be contacted.