A trio of respiratory illnesses is showing no signs of relenting in Alberta, and that's prompting concern about the potential for an even more dramatic surge once people start gathering for the holidays.
As influenza, RSV and COVID-19 continue to overwhelm pediatric hospitals in the province, health officials are warning the worst could be yet to come.
"The concern I have right now is that we are not seeing any substantial downturn in … viral spread at the moment," said Craig Jenne, associate professor in the department of microbiology, immunology and infectious diseases at the University of Calgary.
"Judging by the patterns we've seen in Eastern Canada, it's unlikely we'll see a substantial decrease in viral transmission before the holiday season. And if we continue to gather in large groups and events where there's, for example, no masking indoors, that will further drive viral spread."
Data published by the Public Health Agency of Canada show, for the week ending Nov. 12, Alberta had "widespread" flu activity, and it registered higher than any of the other provinces or territories reporting data at the time.
Canada's chief public health officer, Dr. Theresa Tam, tweeted this week that RSV and influenza are hitting kids particularly hard.
"Influenza detections among children [and] teenagers are unusually high," said Tam. "As a result, pediatric hospitals are reporting unprecedented levels of viral respiratory ER visits [and] admissions."
What has health experts worried right now is the timing.
"If this doesn't begin to plateau or slow before we get into these holiday seasons where there are more social activities, we have seen in previous winters with COVID that typically the holidays do drive a post-holiday spike. And we need to be careful that we have the capacity to deal with … all three of these respiratory infections," said Jenne.
According to Alberta Health Services, the intensive care units at both the Alberta Children's Hospital in Calgary and the Stollery Children's Hospital in Edmonton are operating at close to 100 per cent of their normal capacity.
"We continue to see an early and steep increase in influenza activity in Alberta, with 355 hospitalizations due to influenza since late August.… Of these hospitalizations, 98 have been in children under nine years of age," spokesperson Kerry Williamson said in a statement provided to CBC News.
Letter to parents
With no reprieve in sight, health officials are ramping up their messaging efforts.
In a letter sent through school boards Wednesday, Alberta's new interim chief medical officer of health, Dr. Mark Joffe, warned parents about the severe surge in respiratory viruses. The letter was also signed by AHS senior medical officer of health, Dr. Laura McDougall.
"In the last few weeks, we have seen a large rise in cough and fever type sickness in our schools," it said.
"We are concerned that this influenza season will be more severe than we have seen in years, and that illness will continue to disrupt school, sports and upcoming holiday gatherings."
The doctors noted Australia, which can be a predictor of Canada's flu season, had a severe respiratory virus season, with children under the age of 16 accounting for the majority of that country's influenza hospitalizations.
"While most children who get influenza will recover without complications, some children can get very sick and need treatment in hospital.… H3N2, the common strain of influenza so far in Alberta, is known to cause more severe illness in young children and seniors. The influenza vaccine being used this season provides protection against the H3N2 virus."
Joffe and McDougall pointed to masking as another key precaution parents can take.
"Using a well-fitting, high-quality mask is encouraged, especially in crowded indoor settings. Wearing a mask can help reduce your risk of becoming sick and help protect others from being exposed. Individuals should be supported regardless of their choice to mask or not."
Dr. Jia Hu, Calgary-based public health physician, expects the situation will likely get worse before it gets better.
"People can take steps … that will blunt the peaks of these things," he said.
"We don't have a vaccine for RSV, fair enough. But we do for flu and COVID. So make sure you get that. If you feel the slightest desire [or] concern, it's OK to wear a mask in an indoor public place," he said.
Hu noted influenza vaccination rates are low and COVID immunization rates, in particular for young children, are also lagging.
When it comes to gathering, Hu's key message is to stay home if you're feeling unwell.
"I would definitely hope that people … do take those steps. They're sort of no-brainer steps, in my mind."