As Canadians continue to enjoy the last bit of summer’s sun-soaked days, doctors say they are bracing for a potential “tripledemic” of influenza, respiratory syncytial virus (RSV) and COVID-19, signalling the imminent arrival of respiratory flu season.
Last flu season — which typically runs from November to March in Canada — saw a surge of all three respiratory viruses across the country, especially among children, which was exacerbated by a scarcity of pain relievers, leading to increased hospitalizations and heightened emergency room visits.
The triple threat of respiratory viruses is expected to hit Canadians again, Toronto Public Health’s associate medical officer of health Dr. Vinita Dubey said at a virtual Ontario Medical Association (OMA) conference on Aug. 24.
“We take our lead from what’s happened in the Southern Hemisphere because their winter is before ours,” she said.
“And they certainly have had a busy season with those three viruses, and we did see that again here last year as well, too. So we are expecting this fall to see a heavy respiratory virus season, particularly with those three, RSV, influenza and COVID, among the other viruses spread around that time.”
It may be the first year since the pandemic is no longer considered a global health emergency, “but COVID is still here,” she added.
Australia’s flu season has long been looked at by Canadian health experts in preparation for flu season here. This year’s influenza season in Australia has revealed a significant trend: children aged 16 and younger bore the brunt, constituting 72 per cent of hospital admissions, according to Australian health data. The season was also met with high RSV rates.
Dr. Prabhat Jha, an epidemiologist at Unity Health Toronto, said the severity of this flu season remains uncertain for now, but a potentially clearer picture may emerge by the end of September, in terms of COVID-19 cases.
“When schools reopen and activity assumes in the post-vacation period in September, then towards the end of September, we’ll have some sense of how large the increases might be and we’ll have wastewater and other data to give us some sense of how widespread it is,” he said.
“The flu season, when that arrives is typically a bit later, along with the RSV season.”
What to expect for this fall’s flu season
While cases of respiratory illnesses are currently relatively low, Dr. Andrew Parks, the president of OMA, warned illnesses are likely to rise as the fall and winter set in.
“Historically, we see the rates of these viruses increase in the fall as temperatures drop and people spend more time indoors,” he said during the virtual conference Thursday.
Influenza, RSV and COVID-19 are all primarily transmitted through respiratory droplets. When people gather indoors during colder months, especially in close proximity, these viruses can spread more easily.
RSV and the flu, which typically emerge a bit later in the fall and winter seasons, started earlier than usual last year, meaning all three viruses peaked around the same time.
Last flu season, children’s hospitals across Canada reported significant surges in patients, which led many to cancel major surgeries in order to redeploy staff to help in overcrowded emergency departments and intensive care units.
The situation was further exacerbated by a scarcity of pediatric acetaminophen and ibuprofen and the reopening of school, work and indoor gatherings as COVID-19 mandates lifted.
In his two decades of practice, Anthony Crocco, an emergency room pediatrician at McMaster Children’s Hospital in Hamilton, Ont., said he witnessed the most severe surge of respiratory viruses during last year’s flu season.
“Across the board, we were not only seeing high volume but along with that high acuity with children requiring significant respiratory support and intensive care admission,” he said. “With that experience now… we are now thinking about that as our high watermark that we should be prepared for.”
How doctors, hospitals are preparing
Whether on the provincial, regional or institutional level, there is a concern that “there is going to be another surge of multiple viruses,” this fall season, Crocco warned.
There needs to be a plan in place to navigate the upcoming season, such as increasing staffing and bed capacity and making sure operating rooms are still functioning, he said.
Another plan to help relieve pressure on hospitals is to redirect patients (who have less severe symptoms) out of the emergency department and guide them towards alternative health care facilities, such as cough and cold clinics, family physicians or urgent care.
For example, he said, come mid-September, McMaster Children’s Hospital is launching a rapid access area designed to treat children with less severe symptoms of viral infections.
“To try and redirect them away from the emergency department where we may need those resources allocated for more serious, seriously impacted children,” he explained.
The clinic will function as an “overflow” for the emergency room, operating during evening hours since the highest patient volumes for respiratory illnesses tend to occur at night. The objective is to promptly evaluate patients and discharge them in a timely way, he said.
“So we’re hopeful that that will address some of the increased volumes that we’re seeing,” Crocco said.
Preparations for the upcoming flu season extend beyond hospitals and emergency rooms, but involve family physicians as well, Park said.
“From a practice standpoint, is to ensure that our primary care physicians have a stable supply of their vaccines and are ready to go. That they have a supply of personal protective equipment (PPE) to ensure that when their patients are sick, they are protecting themselves,” he said.
In an effort to mitigate the transmission of the trio of viruses — RSV, influenza, and COVID-19 — Dubey encourages Canadians to prioritize hygiene practices and ensure their vaccinations are current.
“If you are sick, stay home. If your child has a fever, if they have a new or worsening cough, if they have respiratory symptoms that can spread to others, vomiting and diarrhea… keep your child at home,” she said.
“The goal is not to keep them home indefinitely, but when symptoms are improving for 24 hours they can return back to school.”
Similar to the measures implemented during the pandemic, Dubey emphasized the significance of preventive actions, including frequent handwashing, proper cough etiquette, maximizing outdoor time, and acknowledging the need for heightened precautions among individuals at greater risk (such as wearing masks).
And then there is the importance of vaccines, she said.
At the beginning of August, Health Canada approved the first vaccine for RSV for adults aged 60 and over. There is no RSV vaccine for children, but there are two kinds of antibody injections that can be given to high-risk babies to help prevent serious illness.
“We know that RSV and flu, those two viruses can be more serious in children, especially young children. What we learned from the Southern Hemisphere, from Australia and New Zealand, is that children were more impacted by influenza this season. But we also learned that influenza virus strains that circulated were a good match with the vaccine,” Dubey said.
The fall influenza booster is not yet available but typically rolls out in October, she said.
“S0 parents can add to the list, by getting the flu vaccine in the fall. In particular, getting their children vaccinated, and that will be really important for keeping children from getting really sick from the flu,” she said.
“The flu vaccine and the COVID vaccine can be given at the same time this fall.”
As new COVID-19 variants start to circulate across the globe and in Canada, updated booster shots are also expected to roll out this fall.
Canada’s National Advisory Committee on Immunization (NACI) released fall booster guidance in July, recommending a dose of the new formulation of the COVID-19 vaccine.
NACI said 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.
In an email to Global News on Monday, a spokesperson from Health Canada said the department is, “actively reviewing the submissions received from Pfizer-BioNTech and Moderna, seeking authorization for the use of their respective COVID-19 vaccines containing the XBB.1.5 Omicron subvariant, for persons six months and older. The reviews are ongoing.”
— with files from Teresa Wright and Global News’ Isaac Callan and Saba Aziz