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Aarav Shah gets the Pfizer-BioNTech COVID-19 vaccine for children as his mom, Binal Shah comforts him at the Embassy Grand Convention Centre in Brampton, Ont., on Nov. 26, 2021.

Baljit Singh/The Globe and Mail

The National Advisory Committee on Immunization has released new guidelines that favour giving kids a Pfizer-BioNTech COVID-19 vaccine over the newly approved Moderna version.

Health Canada approved Moderna’s pediatric COVID-19 vaccine for kids ages six to 11 on Thursday.

The risk of heart inflammation, known as myocarditis, in Moderna’s child-sized dose is unknown, but the adult dose carries a slightly higher risk of the rare adverse complication in adolescents when compared to the vaccine from Pfizer-BioNTech.

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The advisory committee says Moderna’s vaccine can be offered to kids as an alternative, but the Pfizer dose is preferred for the first two shots because of the potential risk for myocarditis.

Moderna’s vaccine does appear to be slightly more effective, according to indirect data in the adult population.

For that reason, the committee says a three-dose regimen of Moderna may be considered for some immunocompromised kids.

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