Archived 32: Summary of NACI rapid response of February 4, 2022: Updated guidance on COVID-19 vaccination timing for individuals previously infected with SARS-CoV-2

Published: February 4, 2022

On this page

• Overview
• What you need to know
• Quotes

Overview

• On February 4, 2022, the Public Health Agency of Canada (PHAC) released updated guidance from the National Advisory Committee on Immunization (NACI) regarding the timing of COVID-19 vaccination after SARS-CoV-2 infection. These recommendations are based on current scientific evidence and NACI's expert opinion.
• Vaccination continues to be very important, even for those with a prior SARS-CoV-2 infection. NACI continues to recommend that COVID-19 vaccines should be offered to individuals with previous SARS-CoV-2 infection without contraindications to the vaccine.
• Suggested intervals between SARS-CoV-2 infection and COVID-19 vaccination are intended to serve as a guide and are based on the available evidence on the safety, effectiveness and timing of vaccination following infection; immunological principles; and expert opinion. Guidance on suggested intervals between infection and vaccination may change as additional evidence emerges.

At this time, NACI suggests that:

• Individuals who experienced SARS-CoV-2 infection before starting or completing their primary COVID-19 vaccine series may receive their next dose 8 weeks after symptoms started or after testing positive (if no symptoms were experienced).
• Individuals who are recommended to receive a booster dose and who experienced SARS-CoV-2 infection after completing their primary series may receive a booster dose 3 months after symptoms started or after testing positive (if no symptoms were experienced) and provided it is at least 6 months after completing a primary series.
• Additional guidance on intervals between infection and vaccination for individuals who are moderately to severely immunocompromised or who have experienced multisystem inflammatory syndrome in children (MIS-C) are outlined in the rapid response.

For the full update, please see NACI rapid response: Updated guidance on COVID-19 vaccination timing for individuals previously infected with SARS-CoV-2.

For more information on NACI's recommendations on the use of COVID-19 vaccines, please refer to the COVID-19 vaccine chapter in the Canadian Immunization Guide (CIG), as well as additional statements on the NACI website.

What you need to know

• The Omicron variant continues to circulate and cause widespread infection in Canada. People who have a recent history of SARS-CoV-2 infection may be wondering how long to wait after infection before receiving a dose of a COVID-19 vaccine, either to start or complete a primary series or receive a booster dose.
• Vaccination continues to be very important, even for those with a prior SARS-CoV-2 infection. NACI continues to recommend that COVID-19 vaccines should be offered to individuals with previous SARS-CoV-2 infection without contraindications to the vaccine.
• Suggested intervals between SARS-CoV-2 infection and COVID-19 vaccination are intended to serve as a guide and are based on the available evidence on the safety, effectiveness and timing of vaccination following infection; immunological principles; and expert opinion.
• Some studies conducted before the emergence of the Omicron variant noted that past infection offers good protection from re-infection, but that this protection decreases as time goes on.
• While infection alone may provide some protection, vaccination following infection is expected to strengthen the immune response and to provide a more robust and longer-lasting protection against COVID-19.
• The safety profile for people with previous infection is very good and generally comparable to those who have not previously been infected. Limited evidence suggests that side effects may be slightly increased in individuals previously infected with SARS-CoV-2 compared to those with no history of previous infection.
• A longer interval between infection and vaccination may result in a better immune response and longer-lasting protection against Omicron and future variants. Risk factors for exposure and severe outcomes should be assessed when considering longer intervals.
• Additional guidance on intervals between infection and vaccination for individuals who are moderately to severely immunocompromised or who have experienced multisystem inflammatory syndrome in children (MIS-C) are outlined in the NACI rapid response.
• It is important that individuals with SARS-CoV-2 infection wait until they are no longer considered infectious and no longer have any symptoms of acute COVID-19 illness before receiving a dose of a COVID-19 vaccine. This will help minimize the risk of transmission of COVID-19 at immunization venues and allow monitoring of potential side effects from vaccination, respectively.
• Previous infection can be defined in different ways. Provinces and territories will decide how to define previous infection in their jurisdictions.
• Suggested intervals may change as additional evidence on the extent and duration of protection provided by infection emerges. NACI will continue to evaluate the evolving evidence and will update guidance as needed.

For the full update, please see NACI rapid response: Updated guidance on COVID-19 vaccination timing for individuals previously infected with SARS-CoV-2.

For more information on NACI's recommendations on the use of COVID-19 vaccines, please refer to the COVID-19 vaccine chapter in the Canadian Immunization Guide (CIG), as well as additional statements on the NACI website.

Quotes

"We have seen the number of COVID-19 cases rise significantly over the past few winter weeks with the spread of the Omicron variant of concern. This means that many people in Canada will be wondering and asking whether they still need to complete their vaccine series and how long they should wait after infection before receiving their first, or next, dose of a COVID-19 vaccine. While infection alone may provide some protection, NACI continues to recommend that individuals who have been infected complete their primary series and receive a booster dose, when eligible, to better protect themselves against re-infection and severe outcomes from current and future variants of the virus. These suggested intervals between an infection and a vaccine dose aim to improve long-term COVID-19 protection and are intended to serve as a guide. It is expected that evidence on the optimal timing between infection and COVID-19 vaccination will continue to emerge. The Committee will continue to assess new data and update guidance, as needed."

Dr. Robyn Harrison, NACI Vice-chair

"This winter, unprecedented numbers of people in Canada have been infected with the highly contagious Omicron variant. Many of these individuals may now be wondering about the importance of COVID-19 vaccination and whether they should wait for a period of time after infection before starting or continuing with a COVID-19 vaccines primary series or booster dose. NACI continues to recommend that COVID-19 vaccines should be offered to all eligible people, including those with a previous SARS-CoV-2 infection and no contraindications to the vaccines. Complete and up-to-date COVID-19 vaccination is recommended in order to provide the best possible protection against severe illness due to COVID-19 now and going forward. This update with NACI's suggested intervals between COVID-19 infection and vaccination provides a helpful guide for considering optimal timing for getting a first or next dose of COVID-19 vaccines following infection. As always, I thank NACI for their expert advice on how best to use vaccines to protect Canadians against COVID-19."

Dr. Theresa Tam, Chief Public Health Officer