By David Ljunggren

OTTAWA (Reuters) – Healthcare systems across Canada are still very fragile from efforts needed to fight COVID-19, even as signs suggest a fourth wave is starting to recede, a top medical official said on Friday.

Chief Public Health Officer Theresa Tam said it was important for health workers to get vaccinated and prevent hospitals from becoming overwhelmed.

“Everybody’s exhausted. And if health care workers have to go into quarantine for example, after exposure, the system simply isn’t going to be sustainable,” she told a briefing. “Our health systems are still very fragile.”

Official data show that as of Oct. 8, 81% of Canadians aged 12 and over have received two shots against COVID-19.

That said, COVID-19 is still posing serious problems in the western provinces of Alberta and Saskatchewan, which lifted most restrictions in July only to see cases soar.

“Surveillance data from this week indicates that although the virus continues to surge and present ongoing challenges in several areas … overall we’re observing a decline in COVID-19 disease activity nationally,” Tam said.

She also urged Canadians to get their annual shots against the flu, which is worst in the winter months.

“This is definitely not the year to have influenza wreak havoc,” she said.

Ontario, the most populous of the 10 provinces, on Friday began to allow residents to download proof of vaccination on to their devices as a QR code, as well as an application that will allow businesses to verify it.

While businesses such as restaurants and arenas have been required to ask for proof of vaccination since Sept. 22, this took the form of PDFs, which critics noted were easy to edit.

(Additional reporting by Anna Mehler Paperny in Toronto; Editing by Nick Macfie)