Rising rates of COVID-19 in children, adolescents spark concerns about back to school plans

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Rising rates of COVID-19 in children and adolescents in Canada are prompting concerns about the spread of disease and highlighting the need for answers about how well children transmit the virus as daycares and schools reopen.

While people under the age of 20 typically experience a mild form of COVID-19 and are much less likely to have serious complications compared with older adults, the growing number of cases among kids and teens is causing some experts to worry, particularly about the possibility of children spreading the virus to vulnerable groups.

On Tuesday, Ontario recorded its first COVID-19 death in a patient under age 20. Across Canada, 105 people under age 20 have been hospitalized for COVID-19 and 21 have been admitted to the intensive care unit during the pandemic, representing one per cent of all hospital and ICU admissions.

Theresa Tam, Canada’s Chief Public Health Officer, tweeted on Friday that positivity rates in younger people may be rising because they are going out more. Experts also say cases in younger age groups are making up a greater portion of the total as outbreaks among seniors at long-term care facilities get under control. Several provinces have also loosened the rules around who can get a test, meaning that more kids and teens are likely getting swabbed.

But months into the pandemic, little is known about how easily children contract and transmit the virus, as most countries have kept schools and daycares shut, leading to doubts about how to proceed in September.

“There’s so much uncertainty around all of this,” said Ashleigh Tuite, an epidemiologist at the University of Toronto’s Dalla Lana School of Public Health.

The median age of COVID-19 cases in Canada has been dropping since the beginning of April, according to an epidemiological report published by the Public Health Agency of Canada on Friday, reaching 40 as of June 19. And the number of cases in every age group has been declining steadily for that two-month period, except for people under age 20, PHAC says.

People under age 20 accounted for 14 per cent of all new COVID-19 cases in Canada in the past week, up from 11 per cent the week before, according to the PHAC report. And individuals age 29 and under account for about one-third of all new COVID-19 cases across the country in the past week, the report said.

In Ontario, people under the age of 20 made up 10 per cent of COVID-19 cases during the week of June 7, up from 2.7 per cent during the week of March 29, according to figures provided by Public Health Ontario. At the same time, the proportion of older people testing positive is on the decline. People 80 and older made up 5.6 per cent of cases during the week of June 7, down from 15 per cent the week of March 29.

Across Canada, officials are struggling to figure out what the start of the school year will look like. Last week, Toronto’s Hospital for Sick Children released a set of recommendations for reopening schools that said measures such as non-medical masks and strict physical distancing aren’t required. Some public-health experts criticized the document, saying the recommendations aren’t based on sound evidence.

In Quebec, where elementary schools outside of Montreal opened in May, physical distancing and increased hand hygiene are part of daily life. Officials say about half of public school and two-thirds of private school students returned to the classroom. More than 50 students and staff have tested positive for COVID-19 since schools reopened, but officials say no one has become seriously ill.

Dr. Tuite said there simply isn’t enough data on how easily children are infected and how well they transmit the virus because of worldwide lockdowns.

“You’re making these inferences based on an abnormal situation, which is that kids have been at home,” she said. “It’s a completely artificial situation that we’ve created.”

Many children and teens don’t develop the same type of cough or shortness of breath that most adults with COVID-19 do, which can make the disease more difficult to detect. Dr. Tuite said it’s unclear why the positivity rate is going up so quickly in young people.

Tom Lacroix, chief of pediatrics at Bluewater Health in Sarnia, Ont., said he’s seen young patients with COVID-19 who don’t have any respiratory symptoms. He’s also treated children with fevers who are close contacts of confirmed cases, but who test negative, leading him to believe children have a slow onset of COVID-19 and are being missed by testing.

“We’re making a lot of policy decisions on a group in our population who have really gone under-tested and under-reported,” Dr. Lacroix said.

Upton Allen, head of infectious diseases at SickKids, said the recommendations released last week were meant to start a conversation about how to safely get kids back to school.

“We see this as a first step,” Dr. Allen said. “At every single point in time, it’s going to be a careful balance of risks versus benefits.”

Andrew Petrosoniak, an emergency and trauma physician at Toronto’s St. Michael’s Hospital, said the reopening of schools is a “wicked problem,” meaning there is no simple solution. Instead, officials will have to focus on adopting a series of new measures to help mitigate the spread of infection while children enjoy the benefits of returning to school. Officials will have to be flexible and adaptable, trying out new strategies and testing them out to see what works best, Dr. Petrosoniak said.

“There’s no solution,” he said. “It’s a sequence of interventions that will get us gradually to a better place.”

With a report from The Canadian Press

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