Rising influenza numbers tie for highest peak since COVID-19 pandemic

Medical equipment inside the trauma bay photographed during simulation training at St.Michael's Hospital in Toronto on Tuesday, August 13, 2019. (Tijana Martin/The Canadian Press)

Positivity rates for influenza are continuing to rise, with the latest numbers tying the 2022-23 season’s peak for the highest since the COVID-19 pandemic at 24.3 per cent of tests detecting the virus.

Published Friday to the federal Health Infobase dashboard, the updated figures show 10,449 detections of influenza in the week of Feb. 8, with 93.6 per cent detected as influenza A, the dominant subtype for the season.

A total of 83 new outbreaks linked to influenza have been counted, with a weekly hospitalization rate of 3.4 per 100,000 in the population. Infobase notes that known cases of influenza are most concentrated among Canadians aged 65 and up.

Outbreak and hospitalization numbers have increased in recent weeks, according to the dashboard, and positivity rates have seen an accelerating rise since the beginning of the year.

This year’s all-season high of 24.3 per cent has arrived later than in 2023-24, which peaked in late December at 18.7 per cent, and in 2022-23, which reached its maximum positivity rate of 24.3 per cent in the week of Nov. 23.

You can learn more about the latest data on respiratory viruses at CTVNews.ca’s tracker here.

What to know about flu season

Influenza is a contagious respiratory virus that typically causes fever, cough and body aches, as well as chills, fatigue, headaches, sore throat, loss of appetite and runny or stuffy noses, notes the Public Health Agency of Canada (PHAC).

In children, parents are advised to keep an eye out for low energy, difficulty breathing, irritability, and changes in eating and drinking habits, among other warning signs. Children are especially susceptible to gastrointestinal symptoms like nausea, vomiting and diarrhea.

In more severe cases, complications can aggravate chronic health conditions, impact the heart and respiratory system, or lead to pneumonia. Influenza can require hospitalization and, in some cases, may be fatal, PHAC’s influenza fact sheet reads.

Symptoms typically appear between one and four days after exposure, and last for seven to 10 days. A person with the flu is considered contagious from the day before symptoms appear until five days after.

Experts say, those who become ill should stay home, avoid close contact with others until symptoms subside and practise good public health through regular handwashing, covering coughs or sneezes and wearing a well-fitting face mask.

Those at higher risk should seek out their health-care provider if they develop symptoms.