Pfizer shots ready for kids

Different doses, intervals recommended for younger age group

Pfizer COVID-19 vaccines are now available across Ontario for all children aged six months to five years.

About 6,500 children in the age group in Peterborough city and county, Curve Lake First Nation and Hiawatha First Nation became eligible for the vaccine in July when early pediatric Moderna Spikevax COVID-19 vaccine became available across Ontario.

“The Pfizer vaccine is an mRNA vaccine similar to the Moderna vaccine,” said Donna Churipuy, director of health protection at Peterborough Public Health. “The difference is you require three doses of it, versus the two doses that were authorized for the Moderna vaccine.”

Adults only need two doses of Pfizer, she said, but since children under five receive a quarter of the adult dose, three shots are recommended. It’s also recommended that children wait 56 days between each of the three doses, to build a better immune response, she said.

“When Pfizer conducted their studies, they required three doses to get an effective immune response,” Churipuy said. “It is not the same dosage that you would

receive as an adult, it’s actually half the dose that is given to the six-to-11-year-old group.”

Roughly six to seven per cent of children under five have already received their first dose of the Moderna vaccine, she said. However, the province is currently discouraging the mixing of vaccine brands for this age group.

“You have two different products that require two versus three doses,” Churipuy said. “So, it’s important not to mix them.”

This was less of a concern for adults, she said, and when Pfizer and Moderna came out there were also shortages in supply.

“There were no safety concerns with mixing the doses. We had learned enough about them to be able to mix Moderna and Pfizer, but that’s not the case for this age group,” Churipuy said.

Churipuy explained the vaccine has been approved as safe for children under five by Health Canada, but ongoing surveillance and monitoring of safety with any new vaccine occurs over a period of time.

For this reason, it’s also recommended that children aged six months to five years receive no other vaccine, unless urgently required, within 14 days of receiving a dose of the COVID-19 vaccine, she said.

“It’s a fairly new vaccine for children, and we want to be able to differentiate if there are any issues. Most adults have now had three, maybe four doses. So, the same surveillance is not required,” Churipuy said.

“For children at this age, it may be the first time they’ve had multiple vaccines. So, you don’t know if it’s because of an MMR vaccine or the COVID vaccine, if they’re getting both at the same time.”

Churipuy pointed out that it’s important for children under the age of five to be immunized, as there are some complications of COVID-19 that are worse for this age group.

“Multi system, inflammatory syndrome is a particular complication of COVID-19 seen in children under the age of five,” Churipuy said. “It’s rare, but can be a very serious complication, which usually requires hospitalization.”

She said she hopes that more people will consider the available evidence or consult their primary care provider if they have any questions.

“Priming a child’s immune system to be able to respond to COVID, will help their overall wellbeing and health in the coming months,” Churipuy said.

Appointments can be made for children aged six months to five years at the Peterborough Square (lower level of 340 George St N.) clinic, where a clinic for children is taking place Wednesday from 4 to 6 p.m..

Walk-ins are not accepted. Parents and caregivers can book a COVID-19 vaccine appointment for children online at covid-19.ontario.ca/bookvaccine/ or by calling the provincial vaccine booking centre at 1-833-943-3900.

For anyone five and older, walk-in service will be provided Thursday from 10 a.m. to 6 p.m. when the province’s GO Vaxx mobile clinic makes a stop at Lansdowne Place mall.