Health Canada has finally given the green light for Moderna’s COVID-19 vaccine to be used to inoculate youth as young as 12.
The original approval for Moderna in December, 2020, was only for people at least 18 years old.
Moderna applied for authorization for youth in early June, citing a clinical trial of 3,700 youth in which none of the teens who got two doses developed a COVID-19 infection.
Youth as young as 12 in Canada have been authorized to receive the vaccine from Pfizer-BioNTech since May 5.
As of mid-August, 75 per cent of youth in that age group had received at least one dose, and 59 per cent were fully vaccinated.
Health Canada also says the National Advisory Committee on Immunization is meeting next week to discuss whether booster shots should be offered to people with compromised immune systems.
Ontario has already begun to offer boosters to transplant recipients, people with some blood cancers and long-term care home residents.
Health Canada took only a few weeks to approve Pfizer for youth, and has not explained why the Moderna review took more than two months.
“After a thorough and independent scientific review of the evidence, Health Canada has determined that the vaccine is safe and effective at preventing COVID-19 in youth aged 12 to 17,” a spokeswoman wrote in an e-mail Friday.
Europe approved the Moderna vaccine for children more than a month ago. The United States has not yet authorized it for teenagers.
The Pfizer vaccine however was approved for teens just as concerns were rising about rare instances of myocarditis – inflammation of the heart muscle – and pericarditis, inflammation of the sac around the heart – particularly in younger people.
In Canada, 557 cases of the two syndromes have now been diagnosed in people who had received one or two doses of a COVID-19 vaccine, 96 per cent of whom had received either Pfizer or Moderna. Half of the people who developed the syndrome were between 12 and 29 years old.
Over all the rate of the syndromes occurred in less than one in 100,000 people who received the vaccine.
NACI said in a statement Friday that it recommended youth between 12 and 17 get both doses of either Pfizer or Moderna, noting that it had taken into account the concerns around myocarditis and pericarditis.
Chief Public Health Officer Theresa Tam said in her weekly written update that since Pfizer has been used for the nearly two million teens already vaccinated, some provinces and territories might want to just keep using it since they are more familiar with its side effects.
But she said Moderna is still safe to use for that age group.
Both Pfizer and Moderna are in the midst of trials of their vaccines for children younger than 12, with results expected some time this fall.
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