Is the COVID-19 risk to children worse now than in earlier waves?
One of the more troubling aspects of Canada's third wave of COVID-19 has been the impression that the latest round of infections is proving to be a larger threat to young children.
Along with data showing higher provincial and national infection rates among younger age groups has come tragic news of young victims, such as 13-year-old Emily Viegas, who passed away at her home in Brampton, Ont. last week, and the deaths of a 16-year-old in Quebec and a toddler in B.C. in April.
Yet as parents try to figure out how to process the evolving threat of the virus to their children, experts say that while the recent surge in infections represents a threat to anyone not yet fully vaccinated, there’s little to suggest a meaningful shift in the risk to children.
“I don’t actually think that children are at any more risk from problems with COVID-19 than they were at the beginning of the pandemic,” Jeremy Friedman, associate pediatrician-in-chief at The Hospital for Sick Children in Toronto, told CTVNews.ca by phone on Tuesday.
Friedman says Sick Kids has seen a total of 160 children over the course of the pandemic, with typically one or two children in the ward at a time over the first two waves, and three or four in the most recent. But he said this tracks with the overall rise in infections and hospitalizations.
“I think what has changed is that the numbers of cases in the community are at their highest level so I think the risk of children contracting coverage has increased just because of how much of the virus is in the community,” he added.
Helping skew the numbers to lower age groups are infection rates that have fallen in the highest age brackets that were the targets of the initial vaccine rollout. Canadians over 80, for instance, have seen a considerably lower infection rate in the most recent wave than in the initial wave last spring and the second wave last fall.
“If we look at the highest growing age group in terms of infections, that's the 20-39s and then we also have 40 to 59s, and then right after that people 19 and under,” Omar Khan, an assistant professor in biomedical engineering at the University of Toronto, told CTVNews.ca by phone on Friday.
“The 60-and-up group is well taken care of now. Their cases aren’t really growing as quickly.”
New research also confirms that children are less likely to pass on the virus on than adults. A study published in the Canadian Medical Association Journal examined 305 nasal swabs from adults and children who had tested positive for COVID-19 in Manitoba between March and December of last year.
It found that samples from children 17-years-old or younger were about half as likely to grow live virus in a lab setting as samples from adults, “meaning less viable virus was present”. For children aged 10 and younger, the positivity rate was considerably lower than for children aged 11-17, or adults.
“These data, along with our local epidemiology, suggest that children do not appear to be the main drivers of SARS-CoV-2 transmission,” the study concluded.
However, it’s the severe cases that tend to draw attention, and the higher overall rate of infection means that severe cases, though extremely rare for children, have been on the rise, said Khan.
“Even though the percentage of kids who get severe disease are smaller, because we have higher numbers we're going to see more children suffer because of severe disease, simply because more are infected,” he said.
With a larger number of Canadians in their 40s having now received their first vaccine dose, and vaccine shipments expected to pick up in May, infection rates could very well skew increasingly younger over the coming months as more adults receive protection.
However, Khan said the higher numbers of parents now being immunized should eventually confer its own protection on children as there are increasing signs of vaccinations reducing not just illness but also transmission.
A study this week by Public Health England showed that one dose of the Pfizer-BioNTech or AstraZeneca vaccine could reduce household transmission by 38-49 per cent.
“That shows the importance of why we need eligible people to go get vaccinated because it's now kind of one of our only tools to protect this younger population,” he said.
While the opening up of lower age groups for vaccinations is good news, Khan warned that it’s going to take some time before life returns to some semblance of normal, as each vaccine dose takes 2-4 weeks to take full effect, and the timeline for second doses means the current vaccination campaign is likely to continue through the summer.
Beyond that, there are the impact of variants to consider, and the potential for other variants to comes from parts of the world where vaccination rates are much lower.
“As we kind of get things going here we also have to be very aware of what's happening in the rest of the world, and hopefully help because it's a global health problem,” he said.