Ontario through worst of respiratory virus season: chief medical officer

TORONTO — Ontario is through the worst of the respiratory virus season, with the three major viral threats on the decline, though a more transmissible variant of COVID-19 may lead to a "smaller" spring wave, the province's top doctor said Thursday.

Chief Medical Officer of Health Dr. Kieran Moore "strongly" recommended people wear masks in indoor public settings in mid-November, as the flu, respiratory syncytial virus and COVID-19 were circulating and straining children's hospital capacity. 

Moore said at the time that a renewed mask mandate was on the table, but now with the province on the other side of a tough respiratory season after three years of a pandemic, that may be off for good.

"I really can't see us considering that," he said in an interview. 

"In no jurisdiction has there been a mandatory masking recommendation, nor has our expert panel recommended that to us. So we hope the highest-risk Ontarians will continue to take the layers of protection seriously."

Moore said that includes staying at home when sick, practising good hand hygiene and "cough etiquette," and the strong recommendation for indoor masking continues.

As well, he recommends people stay up to date on COVID-19 booster shots, particularly people more susceptible to the virus.

A bit more than half of Ontarians over the age of 70 have received a bivalent shot, Moore said.

"I would love the 45 per cent who haven't come forward to take advantage of the bivalent booster," he said. 

"We know that population has the highest morbidity and mortality ... We know our partners in pharmacies and primary care and public health have vaccines, have openings, so the call is really for them to come forward and get that bivalent booster and stay up to date and stay protected, especially given the unknowns associated with (the XBB.1.5 subvariant) and its increased infectiousness."

The flu in Ontario peaked in early December, with around 568 patients in hospital, and now that number is 80, Moore said. RSV peaked at the same time, with about 350 people in hospital.

"We're now down to 190, so that number is slowly going down with RSV," Moore said. "RSV typically doesn't have that high peak that influenza does, and stays with us throughout the winter months, but its impact is decreasing significantly week by week."

The COVID-19 situation has also been improving, Moore said, with 99 people in ICU, the lowest number since July.

However, previous pandemic years have seen spring waves of COVID-19, so Moore said he is closely monitoring the more transmissible XBB variant.

"This virus has tended to have 90-to-100-day cycles in its mutations, and each subsequent variant has been more infectious," he said. "So we do anticipate having another, smaller wave."

This report by The Canadian Press was first published Jan. 26, 2023. 

Allison Jones, The Canadian Press