Influenza has led to the deaths of at least 37 people this flu season, according to the Public Health Agency of Canada.

While that number is slightly down from the same period last year, with at least six children losing their lives to the virus and more than 540 being hospitalized across the county -- more than double the number of pediatric hospitalizations compared with this time last season -- health-care workers are warning that kids are particularly vulnerable to this year’s dominant influenza strain.

“The severe illness that we’re seeing is unexpected, and to be honest, unprecedented from previous years,” Dr. Tanya Holt, head of pediatric intensive care at the Royal University Hospital in Saskatoon, told CTV News. “We’re seeing more admissions to the intensive care unit and what we know is that the kids that have been admitted to the ICU, none of them have had the vaccine.”

The 2018-2019 flu season at a glance

The predominant influenza strain affecting adults and children alike this year is H1N1, a serotype of the Influenza A virus that caused the deadly Spanish flu pandemic a century ago and the so-called “swine flu” pandemic of 2009 and 2010.

While overall this flu season has been moderate in its intensity, of 14,897 confirmed influenza cases reported as of Jan. 5 this season, 21 per cent have been in children aged four and under while 17 per cent have occurred in people aged five to 19.

Children four and under have also by far been experiencing the highest rate of influenza-related hospitalization of any age group this season, at a staggering 47.69 per 100,000 people. There have also been 540 pediatric hospitalizations due to influenza, including 95 intensive care unit admissions, according to the most recent government data -- figures that are more than double than the same period last year.

That has put an incredible strain on emergency units across the country, including the one at Montreal Children's Hospital.

“We’ve almost had a doubling of presentations to the emergency department and that’s caused… prolonged wait times for patients who are coming for evaluation,” Dr. Harley Eisman, medical director of the hospital’s pediatric emergency service, told CTV News. “Our peak numbers have been over 300 patients a day. (The) sweet spot for an emergency like ours is about 200 patients a day, so we’ve really seen an increase in volumes.”

Ground Zero Saskatchewan?

While the Public Health Agency of Canada’s most recent FluWatch report from Jan. 5 says that there have been six pediatric deaths from influenza this season, as of Jan. 10, Saskatchewan alone has recorded four influenza-related deaths in children under the age of five.

One of those was two-year-old Kaelynn Hansen, who died on Dec. 8 at Saskatoon's Royal University Hospital.

“The severe cases have often been the toddlers,” Holt, who works at that hospital, explained. “But we’re also seeing it in kids that are less than 12. They’re ending up on the ventilator, they’re ending up having prolonged stays in the intensive care unit and some of them have even had complications.”

Twelve-year-old Quinton Kequahtooway, for example, is very lucky to be alive.

After becoming sick in early December, he was flown from a Saskatchewan First Nations reserve to the Royal University Hospital. Close to full organ failure, Quinton was so ill that he had to be put on a respirator while in an induced coma for three weeks.

“We were totally in shock,” his father, Wesley Kequahtooway, told CTV News. “We didn’t know that this could happen to him because he’s a totally healthy kid.”

In total, Quinton spent a month in hospital, much of it in intensive care. Now recovering, he will be returning to his community this week.

Quinton didn’t receive an influenza vaccination, his father says, because the school program that was supposed to give him his flu shot didn’t follow through. That, he added, will not happen again.

“There’s no ifs or ands about it because we don’t want to go through this again,” Wesley Kequahtooway said. “We don’t want anybody going through what we had to go through this past month.”

‘Get the vaccine’

Quinton’s case illustrates the true cost of a disease that some people dismiss as “just the flu.”

Public health officials theorize that young children are being particularly hard-hit this season because they were not born when the H1N1 serotype was last widespread in Canada, thus they were unable to build up immunity. That’s also why public health officials are recommending the flu vaccine as a first defence. This season’s batch, moreover, is being touted as much more effective than last year’s.

“This particular virus is a match to the strain contained in this year’s influenza vaccine,” Canada’s Chief Public Health Officer, Dr. Theresa Tam, told CTV News. “I do encourage Canadians over the age of six months to get the vaccine. It’s not too late.”

Data from the Public Health Agency of Canada shows flu season may have just peaked, but Canadians young and old alike could still be at risk of contracting the infectious disease for weeks to come.