Canada faces start of Delta-driven 4th wave of COVID-19, Top doctor says

Canada is at the start of the Delta-driven fourth wave of COVID-19, Canada's Chief Public Health Officer Theresa Tam said on Friday.

"The updated longer-range forecast shows how the epidemic trajectory may evolve through early September. It suggests that we are at the start of the Delta-driven fourth wave, but that the trajectory will depend on ongoing increases in fully vaccinated coverage, and the timing, pace and extent of reopening," Tam said at a press conference in Ottawa.

"I think we are in a slightly precarious period at the moment, in between these people trying to get the vaccines in and reopening," she said.

"As soon as that balance is tipped, and it wouldn't take very much with a highly transmissible virus, you're going to see an uptick in cases."

After weeks of sustained decline in new cases of COVID-19, Canada is seeing an increase in new COVID-19 cases, and thousands of more infections are predicted if contacts aren't contained, according to national modelling released by the Public Health Agency of Canada (PHAC) on Friday.

The seven-day moving average of 594 new cases reported daily (July 22-28) showed an increase of 39 per cent over the previous week, said the PHAC on Thursday.

The national modelling released by the PHAC on Friday showed the serious threat the highly contagious Delta variant is posing, and the risk that the unvaccinated may be to the country being thrust into the fourth wave.

As of Friday, 80.5 per cent of those eligible have received the first dose in Canada, while 65.8 per cent are now fully vaccinated.

The PHAC warned that if community-wide contact rates increase too quickly with ongoing reopening efforts, the long-term forecast indicates Canada could experience a "stronger resurgence" of the virus.

The Delta variant "underscores the need for high vaccination coverage and continued caution as restrictions are eased," according to the modelling.

The modelling predicts that in the short term, the case count will continue to increase, meaning the country could see between 2,700 and 11,800 new cases over the next week or so.

As of Friday afternoon, Canada reported a cumulative total of 1,430,289 COVID-19 cases, including 26,589 deaths, according to CTV.