The National Advisory Committee on Immunization (NACI) recommended earlier this month people at high risk of severe disease get another COVID-19 booster shot in the spring.
With the most recent messaging targeting particular groups and cases of COVID-19 appearing to be steady across the nation, many Canadians may be asking if and when they should plan their next booster injection.
Here is a summary of NACI’s current COVID-19 vaccination recommendations for both infants and people who are at high risk of severe illness and those who are not.
PRIMARY VACCINE SERIES
Aside from a very small number of individuals who have valid medical exemptions, NACI recommends that all Canadians aged five and up receive a complete primary immunization series against COVID-19. The number of doses thought to make up a full series depends on the vaccine and the individual being vaccinated.
A complete series consists of two injections about eight weeks apart for people of most ages getting either the Pfizer-BioNTech Comirnaty or Moderna Spikevax vaccine and who are not mildly or seriously immunocompromised.
A complete set of three injections, eight weeks apart, is recommended for children aged six months to four years old who are getting the three-microgram pediatric formulation of the Pfizer-BioNTech Comirnaty vaccine. The Moderna Spikevax original vaccine is still given in two dosages, eight weeks apart, to children aged six months and up.
NACI’s guidance for children aged six months to under five years old is that they “may be immunized with a primary series of an authorized mRNA vaccine,” what the organization calls a “discretionary recommendation.”
A full course of the Novavax Nuvaxovid or Medicago Covifenz vaccine consists of two to three injections. A complete course of the AstraZeneca Vaxzevria vaccine is two doses plus one mRNA vaccine, whereas the Janssen Jcovden vaccine is one dosage plus one mRNA vaccine.
BOOSTER DOSES
Because vaccine protection declines over time, and the COVID-19 Omicron variety and its sub-variants continue to spread in Canada and around the world, NACI and Health Canada suggest booster doses six months after the last dose of a main course for everyone aged five and up.
“It remains important to stay up to date with your COVID-19 vaccines, including recommended booster doses, given the continued circulation of SARS-CoV-2 virus variants in Canada and elsewhere,” Dr. Theresa Tam, Canada’s chief public health officer, said in a media release on March 3. “Booster doses help to build back protection against severe disease that wanes over time after COVID-19 vaccination or infections.”
According to the most recent Canadian Immunization Guide, completely vaccinated adults 65 and later should have gotten one booster dosage since the start of the autumn, regardless of prior booster doses. The same advice is given to adolescents as well as adults aged 12 to 64 who are at greater risk of serious sickness from COVID-19, including those who are immunocompromised.
Children aged five to eleven who have an underlying medical condition that puts them at raised risk of serious sickness due to COVID-19 should also be increased, according to NACI. There are no approved COVID-19 vaccine boosters for children under the age of five.
Correction
A previous version of the article claimed that children aged six months to five years should receive a main set of vaccinations. For this age range, NACI’s advice is discretionary, stating that students may have a primary sequence. It is recommended that anyone aged five and up have this series.