When Matthew Seabrook brought his 10-year-old son to receive his first dose of the COVID-19 vaccine in late November, a wave of relief washed over London, Ontario. dad.
He was happy to immediately schedule his son for dose n. 2 eight weeks later, by the end of January.
To Seabrook, it all seemed “reasonable” and hopeful, as one of the great burdens of the COVID-19 pandemic for parents – getting their children the best vaccine protection available – could finally be lifted off their shoulders.
“A big priority for us has been doing everything we can to make sure he can go to school in person this year,” Seabrook, who, along with his wife, homeschooled their son last year. “We are very happy to give her her first dose.”
That first dose happened days before Omicron arrived in Canada. And that was enough time to change Seabrook’s perspective.
“As it stands, looking at Omicron’s rate of increase, it is very possible that this wave will hit us on January 22,” he said. “The landscape seems to be changing quite dramatically.”
Parents like Seabrook are now making decisions about whether to try to get a second dose for their children before the eight-week interval recommended by the National Advisory Committee on Immunization (NACI).
There are competing factors. On the one hand, in tests conducted by Pfizer, the vaccine manufacturer for the children’s doses, the doses were given three weeks apart and that interval was determined to be safe and effective. The United States is administering doses of vaccines to children at a three-week interval based on the results of these trials.
But data over time has shown that a longer interval between doses for adults has resulted in longer-lasting immunity, and NACI says there is reason to believe that a longer interval may reduce the likelihood of a rare side effect. which is sometimes seen after taking the vaccine. , myocarditis.
Although the NACI recommendation is for an eight-week interval, the vaccine for children is approved by Health Canada and Public Health Ontario for use at a three-week interval.
Clinical trials of the vaccine in children ages 5 to 11 were conducted at a time when Delta was the primary strain circulating in the US, and at that time two doses were found to be more than 90 per percent effective in protecting children from developing COVID. -19, with efficacy after unknown dose.
Adding Omicron to the mix adds additional uncertainty. Pfizer has said that for adults, a third dose of vaccine may be necessary to “neutralize” the virus according to preliminary studies, but it is not yet known if the same applies to children.
And in Canada, third doses for children will not be a practical consideration until a substantial group has their first and second doses.
The uncertainty about how much protection children receive from a single dose of vaccine is prompting some parents to seek at least a second dose more quickly.
In an email to the Star, Adam Ratner, chief of the pediatric infectious diseases division at Hassenfeld Children’s Hospital in New York, said that “vaccinating children is extremely important both to provide direct protection and to help improve protection for children. community level, “and that the US uses the three-week interval because that’s what has been studied and shown to be safe in clinical trials.
Some parents who initially adopted the logic of extending the time between doses for children are now wondering: Should rapid transmission of the Omicron variant change the strategy?
For Samir Gupta, a clinical scientist at St. Michael’s Hospital in Toronto, Omicron has changed the equation.
For her six-year-old daughter, she says, she is now looking to increase her second dose of the COVID-19 vaccine so that there are only three weeks between doses.
“Initially, we were eager to get that second dose, but (we were) balancing that excitement with the knowledge that a little better and longer-lasting protection can come from the delay,” he said.
“Omicron really changed everything for us. It creates a great deal of urgency. “
Projections shared by Dr. Theresa Tam last Friday showed that if Omicron surpasses Delta as the dominant variant of COVID-19, it could result in 26,600 new daily infections in Canada by mid-January, more than double the cases seen. during peak transmission. of the Delta variant. There are still unknowns, even if Omicron will cause a disease as severe as Delta.
Dr. David Goldfarb is associate clinical professor in the department of pathology and laboratory medicine at BC University Goldfarb has two recent publications, one in the Journal of the American Medical Association, on dosing ranges that explain that a stronger response comes with lag intervals.
Goldfarb said that studies in adults, the results of which translate to children, show that a longer interval between injections provides a higher level of long-term protection.
He said that although people may want to get a second injection for their child more quickly, it is not necessarily the best approach.
“I think it’s reasonable at this point to want to have a lot of different layers of protection when we see a new variant that seems to be spreading and we’re expecting, probably, an Omicron wave,” he said. “This is an area where I think it’s not really going to add a lot of extra protection and may, in the long run, reduce the protection that children will have.”
He stressed that the situation could be different for immunosuppressed children, in which case the child’s doctor should be consulted.
A longer wait may also reduce the rare risk of myocarditis, some initial studies in Ontario suggest, he said.
For Gupta, Omicron’s rapid transmission still tips the balance in favor of vaccinating his six-year-old son.
“I can’t really quantify the pros and cons of giving the second dose at three to eight weeks,” he said. “Except I’m scared of Omicron in those five weeks that my son wouldn’t be fully protected.”
“There is no right or wrong, but I have a feeling that many of us would err before protecting our children,” he said.
Reference-www.thestar.com