COVID-19 and other respiratory viruses are expected to make a resurgence in the fall when schools reopen across Canada, experts are warning.
After more than three years of COVID-19, reported cases have decreased or remained stable nationally.
However, that trajectory is likely to change with the virus rates increasing in the fall, particularly among children, as they congregate in schools and other indoor spaces, said Dr. Jesse Papenburg, a pediatric infectious disease specialist at the Montreal Children’s Hospital of the McGill University Health Centre.
“I think most people expect that there will be a certain amount of seasonality to COVID-19, and we do expect that the case counts will rise in the fall and winter,” he told Global News in an interview Wednesday.
“How much of a surge it will be remains to be seen.”
Scientists are keeping a close eye on a new subvariant of Omicron – named EG.5 – that accounts for the largest proportion of new COVID-19 cases in the United States and has recently made its way into Canada.
The World Health Organization (WHO) said in an update Wednesday that EG.5 has a “growth advantage” and “immune escape characteristics” which could cause a rise in COVID-19 cases, making this Omicron lineage the dominant version of the virus globally.
Vaccinations are the best way to protect families from infection as they reduce the risk of medically attended disease and hospitalization, Papenburg said.
Masking and testing are other effective tools to counter “a cascade of transmission” as schools open next month, said Dr. Prabhat Jha, an epidemiologist at Unity Health Toronto.
While children “very rarely” get sick from COVID-19, the virus can spread to their parents or grandparents who are more vulnerable to the virus, he told Global News in an interview.
Who should get a COVID-19 booster?
Canada’s National Advisory Committee on Immunization (NACI) released fall booster guidance last month, recommending a dose of the new formulation of the COVID-19 vaccine for the authorized age groups.
NACI says all Canadians aged five years and up should get a COVID-19 booster in the fall if it has been at least six months since their last vaccine dose or infection, whichever is later.
The agency also continues to strongly recommend that anyone five years of age and older who hasn’t yet been vaccinated be immunized with a primary two-dose series of an mRNA vaccine.
An Omicron-containing bivalent vaccine is currently available to Canadians, but NACI anticipates that the new vaccine formulations could be available this fall.
While an Omicron vaccine is ideal, any booster that is available is going to be effective at reducing infection, Jha said.
COVID-19 boosters are especially important for children with underlying medical conditions that put them at a higher risk of severe COVID-19 infection, Papenburg said.
The end of August or September is a “good time” to be thinking about getting a booster shot if families feel that’s the right thing for their child, he advised.
Currently, there are no authorized boosters for children aged six months to under five years in Canada, but Papenburg said approval from Health Canada might come in the fall.
What about flu and RSV?
COVID-19 is not the only virus that could surge when schools reopen and the weather cools, experts say.
Canada could see another “tridemic” as it did last fall, with the triple threat of COVID-19, flu and RSV, Jha said.
There is concern about the impact on Canadian children of influenza this year given the surge of pediatric hospital visits during Australia’s flu season, which typically runs from June to October.
An annual influenza vaccine is recommended for all children aged six months of age and above in Canada.
Flu shots are typically made available to the public across different provinces in October or November.
The spread of respiratory syncytial virus (RSV) – another common seasonal virus – was unusually high among children last year.
RSV season in Canada usually starts in the late fall and lasts until spring.
RSV is very contagious among kids under five years of age and can cause serious infection in babies, but it’s not a disease that is exclusive to young children.
Last week, Health Canada approved the first vaccine for RSV for adults aged 60 and over.
Earlier in April, the agency also authorized a new antibody drug, Nirsevimab, to help protect babies from serious illness as a result of RSV.
The drug, which is given by injection, is also authorized for children up to two years of age if they are at risk of serious infection, according to Health Canada.
As availability is “very limited” in Canada, provinces are currently in the process of deciding how this drug can be used, Papenburg said.
— with files from Global News’ Katherine Ward and Katie Dangerfield and The Canadian Press