Students enter Pierre Laporte Secondary School as secondary school students return to class full time during the COVID-19 pandemic in Montreal, on Monday, March 29, 2021.

Image Credit: THE CANADIAN PRESS/Paul Chiasson

MONTREAL - Severe cases of COVID-19 were very rare among Canadian children during the first waves of the pandemic, according to a new study by researchers who warn the findings should not be taken as a reason not to vaccinate youth.

The study was published Monday by the Canadian Medical Association Journal and looked at 264 reported cases of children hospitalized in Canada between March 25 and Dec. 31, 2020, before the more infectious Delta variant emerged.

Of those cases, 43 per cent had been hospitalized for another reason, such as a fracture, and it was only after they were admitted that the positive test came to light.

Nearly 34,000 Canadians of all ages were hospitalized during the same time frame.

"If you look at the numbers in total, that's only 150 children hospitalized with COVID during the first two waves here in Canada," said study co-lead author Dr. Fatima Kakkar of Montreal's Ste-Justine Hospital.

"These are very small numbers, when you compare with what has happened in adults."

The study was conducted before the emergence of the more infectious Delta variant, which now accounts for most COVID-19 infections in Canada.

The research also took place before COVID-19 vaccines were authorized for youth aged 12 and older. Of the cases studied, 77 involved kids aged 13 to 17. Pfizer has said it intends to seek authorization soon for a vaccine intended for kids aged five to 11.

Researchers originally believed that children may be at higher risk for severe disease, since this is typically seen with respiratory infection in the pediatric population.

Among the 150 children admitted directly because of the coronavirus, the most common symptoms were fever (70 per cent) and cough (34 per cent).

Half had a severe form of the disease, with 21 per cent admitted to intensive care and 13 per cent needing respiratory or cardiac support.

Researchers add that more than three per cent of Canadian children — a high among all age groups in the country — have recently been shown to carry antibodies to COVID-19, indicating that they have been exposed to the virus.

But the relatively small number of pediatric admissions shows that children had less severe infections than adults, even though they were potentially infected more often, Kakkar said.

Overall, 39 per cent of children and youth hospitalized for COVID-19 had at least one co-morbidity and those with severe disease were more likely to have an underlying health condition including obesity, neurological or respiratory issues.

"We often talk about children who have comorbidities and who are sicker, (...) but 60 per cent had no comorbidity," she said.

"They were healthy children who were hospitalized for the disease. On the other hand, when we look at the severity, the most severe cases were in children who had comorbidities, such as obesity, major neurodevelopmental disorders."

Deaths of children infected with COVID-19 were also very rare, confirming the findings of other studies.

But even with the encouraging conclusions, parents should not take from it a false sense of security and not vaccinate their child, Kakkar said, given children in good health also ended up in hospital.

"We do not know, among these children who are in good health, which will be the sickest, and we know that when we have a severe disease, we have consequences," Kakkar said.

"A child intubated in intensive care needs months of rehabilitation, and unfortunately we cannot predict which child will fall into this category.'

An unvaccinated child will also be more likely to continue the spread of the virus within their own family and friends.

She also noted the Delta variant is much more transmissible and currently wreaking havoc among unvaccinated adults.

"I do not want to discourage parents at all from having their child vaccinated," she said. "We really have to look at the total well-being of the child: what will allow them to have a normal life, to do activities, to play sports, to see friends? It's vaccination."

Still, Kakkar said the benefits of attending school and seeing friends are essential to development.

"There is a lot of anxiety among parents about the risk of COVID in children," Kakkar said.

"It is important to reassure parents, it is not the same disease as in adults, (so) I hope that will allow the children to live a little more normal life."

This report by The Canadian Press was first published Sept. 27, 2021.

News from © The Canadian Press, 2021