Health officials announced the decision in a press conference on Friday, with the specific timeline of the vaccine rollout to be announced later in the day.
“This authorization comes at a critical time in the pandemic,” said Supriya Sharma, the chief clinical adviser at Health Canada, noting that COVID-19 “incident rates” have been increasing among children under 12.
“While children are less likely to experience complications, they can still get very sick. Although the risk of severe illness is lower in children than in adults, it’s still there,” she said.
On Oct. 18, Health Canada received an application from Pfizer-BioNTech to expand the use of its vaccine, known as Comirnaty, to children aged 5-11. The vaccine was authorized for those aged 16 and older on Dec. 9, 2020, and was later authorized for children aged 12 to 15 on May 5, 2021.
Theresa Tam, Canada’s chief public health officer, said the specific timeline of the vaccine rollout will be announced in a separate press conference on Friday.
“We have been working very closely with a manufacturer, and after authorization from Health Canada we expect to get our supplies very quickly,” Tam said.
Health Canada said clinical trials found the Pfizer vaccine to be 90.7 percent effective in preventing COVID-19 in children aged 5 to 11. To determine if the vaccine is effective, Health Canada compared the response of the children aged 5 to 11 with the response of adolescents and young adults aged 16 to 25.
During the clinical trials, roughly 4,600 children aged 5 to 11 were tested, with 3,100 of receiving the vaccine and 1,500 receiving a placebo, according to the health officials.
“The main adverse events reported were similar to those and adolescents and young adults but were less frequent, except for redness and swelling at the injection site, which were slightly higher,” Sharma said.
Other adverse events reported included fatigue and headache, which Sharma said were mostly “mild to moderate in severity.” She noted that among the 3,100 vaccine recipients, four reported serious adverse events but they were determined to be unrelated to the vaccine. So far, there are no reports of myocarditis, pericarditis, or severe allergic reactions.
Since last spring, a small number of cases of myocarditis (inflammation of the heart muscle) and/or pericarditis (inflammation of the lining around the heart) following immunization with COVID–19 vaccines have been reported in Canada and internationally, including Israel, the United States, and Europe.
According to Harvard University’s Medical School, cases of myocarditis and pericarditis have been most common in male adolescents and young adults, occurring most often after the second dose.
The National Advisory Committee on Immunization is recommending an interval of at least eight weeks between the first and second dose.
Health Canada says that in keeping with transparency, it will publish a number of documents relating to the approval, including a high-level summary of the evidence it reviewed.
When asked if there will be a push to encourage parents to have their children vaccinated, Tam said there will be a media campaign “coming shortly.”
She said the government has been working with health-care professionals, including pediatricians, family physicians, and pharmacists so that “all of these players will accelerate the support and communication and provision of information to parents.”
“We will also be engaging people who parents connect with on social media and other channels as well, so you will see that escalating in the coming days,” Tam said.