As COVID case counts steadily climb in Ontario concerns about a fifth wave of the pandemic are growing.

The chances of Ontario heading into a fifth wave seem high, according to one top doctor.

Dr. Malgorzata Gasperowicz, a developmental biologist at the University of Calgary, told Maclean's that Canada's chances of going into a fifth wave are considerable this winter.

Dr. Malgorzata Gasperowicz has been modelling the pandemic using the skills she developed as a developmental biologist. Right now, she’s worried about what she’s seeing in the data: she rates the likelihood of a fifth wave as 7 or 8 out of 10. https://t.co/uIrGdHVK1v

— Maclean's Magazine (@macleans) November 25, 2021

"We're in a very risky state," she said. "It all depends on what our politicians will do."

Ontario, which lifted many lockdown measures in October, could be at higher risk. She notes Ontario has nearly doubled its daily average of case counts in the past three weeks.

But Ontario's Chief medical officer of health Dr. Kieran Moore said the province is actually still in the fourth wave that started earlier in September. This is not the start of a fifth wave, Moore said this week.

"We never declared the fourth wave over, this is simply a continuance," Moore told reporters.

He thinks the fourth wave will continue into the winter.

"Sadly, all modelling would predict this would slowly, steadily rise and increase over the coming months, including January and February."

And now the possibly vaccine-resistant COVID variant entering Canada is stoking more fears of a surge in cases. Premier Doug Ford asked the federal government to ban flights from countries of concern.

This morning, I was briefed by Dr. Kieran Moore, Ontario’s Chief Medical Officer of Health, about the new variant that’s been found in several countries.

I am extremely concerned about the risks it poses. The federal government needs to act today. pic.twitter.com/GqzheTXfS1

— Doug Ford (@fordnation) November 26, 2021

"I was just briefed by Dr. Kieran Moore, Ontario's Chief Medical Officer of Health, about the new variant that's been found in several countries in Africa that early reports suggest could be vaccine resistant. I have contacted the federal government to express my extreme concern about the risks it poses and the need for immediate action today," Ford said.

Cases of the new B.1.1.529 variant have been found in Botswana, South Africa and Hong Kong.

The worry has even delayed flights coming into Toronto.

@brianlilley some flights from South Africa may not arrive in Toronto later today after all. https://t.co/FXyo0amvso

— houseofno (@houseofno) November 26, 2021

"I am extremely concerned about the risks it poses," Ford Tweeted. "The federal government needs to act today."