Ottawa Public Health (OPH) has announced a plan to deliver a lower-dose version of the Comirnaty COVID-19 vaccine to children aged five to 11.

According to Canada’s Chief Public Health Officer Dr. Teresa Tam, Health Canada has approved the Pfizer-Biontech vaccine for younger children. The vaccine was previously only available to youth aged 12 and up.

The vaccine will contain only 10 micrograms, or one third of the adult dose. The doses will be administered at least eight weeks apart, as recommended by The National Advisory Committee on Immunization (NACI).

Tam made the announcement on Friday, saying the vaccine would allow a greater portion of Ottawa’s population to achieve full immunization.

“Approval of a pediatric COVID-19 vaccine has been long anticipated,” said Tam. “Today, the new lower-dose pediatric formulation of the Comirnaty COVID-19 vaccine by Pfizer-Biontech is being authorized by Health Canada as Canada's first COVID-19 vaccine for use in children ...in this age group who do not have contrary indications to the vaccine.”

According to data from Public Health Ontario, children 17-and-under represent 18.7 per cent of Ontario’s population, but accounted for 12.9 per cent of the province’s total confirmed COVID-19 cases between Jan. 2020 and June 2021.

Tam said that evidence has shown a longer interval period between doses will improve the lasting immunity provided by the vaccines. She said that the lower dose of 10 micrograms for younger children is just as effective as the 30 microgram dose for adults.

“Data shows that the 10 microgram dose works very well at preventing symptomatic COVID-19 in children aged five to 11 years, with an estimated efficacy of 90.7 per cent,” said Tam. “This is very similar to the level of protection achieved with a 30 microgram dose in adolescents and adults, given the current and prevailing epidemiology of COVID-19 in Canada, where incidence rates have remained highest in children aged five to 11 years for most of the fourth wave.”

A news release from OPH stated that 77,000 first doses of this new vaccine will be available “within four weeks of the vaccine authorization and delivery.” The release also indicated that three new vaccination hubs would open in the coming weeks, giving Ottawa a total of seven public centres offering COVID-19 vaccines.

Appointments for children five to 11 years old are not yet available, but OPH says more information on how and where to book an appointment will be released in the coming weeks.

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