Flu cases down, COVID-19 activity on the rise: Toronto Public Health

Toronto Public Health, citing the latest data as of Jan. 10, says flu cases are declining while COVID-19 activity is trending upward once again. (Evan Mitsui/CBC - image credit)
Toronto Public Health, citing the latest data as of Jan. 10, says flu cases are declining while COVID-19 activity is trending upward once again. (Evan Mitsui/CBC - image credit)

The worst of flu season appears to be over but COVID-19 cases are on the rise again, according to Toronto Public Health (TPH).

Toronto's Medical Officer of Health Dr. Eileen de Villa presented the latest data, with metrics as of Jan. 10, to the city's board of health Monday, showing flu season appears to have peaked just as COVID-19 indicators show that virus is on the rise.

"In recent weeks, COVID case activity has steadily increased while flu case activity has significantly decreased," said de Villa.

"We will continue to monitor, of course, to see how this continues."

In the last few months, hospitals across Ontario have been battling unprecedented levels of respiratory illnesses, particularly RSV, COVID-19 and the flu. TPH says RSV, which put a severe strain on children's hospitals, has since stabilized to seasonal levels and flu cases have significantly declined.

The recent uptick in COVID-19 activity may be in line with Ontario's top doctor's prediction that there's of another wave of infections expected in the province this month.

In December, Ontario's Medical Officer of Health Dr. Kieran Moore predicted a rise in COVID cases in early to mid-January and recommended "layers of protection" to fend off respiratory infection.

As of Jan. 10, 17 per cent of COVID-19 lab tests from Toronto came back positive — more than four percentage points higher than the province's positivity rate at 13.6 per cent. The rolling weekly incidence rate of newly confirmed COVID-19 cases, expressed per 100,000 residents, sits at 52.

While these indicators show an uptick in infection, De Villa noted wastewater surveillance trends are decreasing, and TPH is keen to see how that will reflect in clinical data and hospitals.

Toronto Public Health
Toronto Public Health

De Villa says severe outcomes such as hospitalization and ICU admission are still low. She noted the latest COVID-19 variant XBB.1.5 is the most transmissible seen so far, and is spreading quickly in the United States and Europe.

"But at this point, levels in Ontario remain low," de Villa said, adding infection with this variant doesn't seem to lead to higher rates of serious illness.

"The best information we have at this point suggest that continued use of existing layers of protection are still very important and continue to reduce the risk of severe outcomes associated with these new COVID-19 subvariant infections."

De Villa says vaccination campaigns have been largely focused on those with increased risk to the virus. Since the fall, tens of thousands of boosters have been given, TPH data shows, with 73 per cent of Torontonians 60 and over having received a booster.

Influenza, RSV numbers down 

In the Monday update, TPH said influenza activity started and peaked earlier than usual, coming to its highest point in December.

This season saw almost 4,000 confirmed cases so far — a sharp increase compared to previous five years before the pandemic, which saw a cumulative average of a little over 3,000 cases by the end of flu season.

De Villa says at this point TPH can't say why this happened, but it followed similar trends in jurisdictions in southern hemisphere.

"I don't know that we have fulsome explanations for all these interesting phenomena," she told the board.

Children's hospitals getting back on track

Meanwhile, levels of respiratory syncytial virus, or RSV, are sitting at seasonal levels. In recent months, RSV was also hitting Ontario hospitals earlier than normal, but started to slow down late November.

Pediatric hospitals across Ontario have had to cancel surgeries in order to deal with a major surge in respiratory illnesses, but there are signs that demand is easing.

Toronto's Hospital for Sick Children began increasing surgeries Monday after it ramped down surgeries mid-November to attend to its overwhelmed intensive care unit and ER, saying it has seen the number of patients stabilize to volumes usually seen this time of year.