OTTAWA -- Health Canada approved a COVID-19 vaccine booster for children on Friday that targets more recent variants of the coronavirus, along with the original strain.
The Pfizer-BioNTech "bivalent" shot protects against the most prevalent subvariants of Omicron, BA.4 and BA.5, and is the first approved for use in children ages five to 11.
In a press release, Health Canada said that after the thorough review it has found the vaccine is safe and effective and that its benefits outweigh any potential risks when used as a booster dose.
The child-sized dose is about a third of the dose that is approved for people over the age of 12.
The National Advisory Committee on Immunization strongly recommends children with weakened immune systems or underlying medical conditions be offered a dose of the new vaccine at least six months after they receive their first two COVID-19 shots.
The recommendation for other children in that age group is more discretionary, and NACI suggests the bivalent booster "may be" offered.
For now, kids five to 11 are only recommended to get one COVID-19 booster shot, though NACI says an extra booster could be considered at the discretion of family doctors for children who are at higher risk.
"At this time, it is not assumed that every child will need a COVID-19 booster dose but they are particularly important for children five years of age and older with underlying conditions that place them at high risk of severe illness from COVID-19," Dr. Shelley Deeks, chair of NACI, said a statement.
She said the new vaccine is preferred as a booster for kids because it is expected to perform at least as well as the original booster and may have extra benefits against newer variants.
The NACI recommendations noted that although about 40 per cent of children aged five to 11 have had their primary COVID-19 vaccination series, only five per cent of kids in that age group have had a booster dose and that the availability of the bivalent shot "may increase acceptance and uptake of pediatric COVID-19 vaccines."
Dr. Cora Constantinescu, a pediatric infectious diseases specialist with the Vaccine Hesitancy Clinic at Alberta Children's Hospital, said the bivalent booster will provide "more tailored protection" and could be especially beneficial for kids who have not been infected with the Omicron variant.
"Being able to have a tailored type of continued protection is reassuring for a lot of parents," Constantinescu said.
Parents who were already planning to get their children boosted will likely be the ones who seek out the bivalent shot, she said, noting that she's "not convinced" it will increase overall vaccine uptake in that age group.
NACI now also recommends that COVID-19 vaccine boosters can be given to children aged six months and older at the same time as other routine vaccines like the flu shot without a waiting period in between. Deeks said in her statement that she hopes the new recommendation will help children catch up on shots they may have missed during the pandemic.
Canada's chief public health officer, Dr. Theresa Tam, said in a statement that most children who catch COVID-19 experience only mild illness, and the risk of being hospitalized is lower for vaccinated children than those who are unvaccinated.
The Omicron wave of the pandemic has seen far more children infected with COVID-19 than previous waves, given the high level of infection overall, she said.
No unexpected safety concerns were flagged with the new vaccine in the five to 11 age group.
Pfizer-BioNTech must continue to provide data from ongoing studies and real-world use of the vaccine to Health Canada to make sure the benefits continue to outweigh any risks, and to alert the drug regulator to any new safety concerns.
Health Canada and the Public Health Agency of Canada say they will keep a close eye on the safety of the vaccine in Canada and internationally.
-With files from Nicole Ireland in Toronto
This report by The Canadian Press was first published Dec. 9, 2022.
This report has been produced with the financial assistance of the Canadian Medical Association. It has no say in editorial choices.