Ontario could see upwards of 10,000 new cases of COVID-19 a day by New Year's Eve and will likely have to reintroduce some capacity limits in order to protect the health-care system while it embarks on a broader rollout of third doses, the head of the province's science table says.

Dr. Peter Juni, who is the scientific director of the Ontario science advisory table, made the comment during an interview with CTV News Toronto’s Colin D'Mello on Wednesday.

"This trajectory won't change without public health measures, and this means that we're above 10,000 cases a day before New Year's Eve," Juni said.

"You have to do enough that you basically can get this curve down ... and bring it relatively flat and keep it flat for as long as we need to get to roughly 50 per cent of the eligible population vaccinated with a third dose."

"If you can do that in, you know, three to four weeks, great. This is not forever. But you know it's really an extraordinary circumstance and nobody has seen what's happening right now."

Juni said he thinks people need to stop "thinking (Omicron) will be mild" or "it's not a problem."

"Of course it's a problem," he said. "Even if it were half as severe it wouldn't help us a penny, nothing."

A new report from Public Health Ontario suggests that the Omicron variant likely already accounts for more than 80 per cent of the COVID-19 cases being confirmed in the province each day, based on projections that take into account likely time lags in the incubation period.

The same report also estimates that each Omicron case identified in Ontario between Nov. 28 and Dec. 9 infected 7.7 times as many people as each case involving the previously dominant Delta variant, underscoring the real threat that the province faces.

The authors of the report says that Ontario will need to "rapidly implement public health responses to contain the rapid spread of Omicron," though they don't provide specific recommendations.

'NOT GOING BACK TO SQUARE ONE'

In his interview with CTV News Toronto, Juni seemed to suggest that Ontario can avoid the sort of widespread lockdown it had to put in place in the spring, but he said that that capacity limits will have to reintroduced for many venues and the rollout of third doses will need to be accelerated significantly.

"It is not going back to square one with public health measures, that's really important. We learned what is high risk. But unfortunately for restaurant owners, restaurants are high risk. Unfortunately for people who organise a Christmas party at all, that's high risk,” he said.

"It's about capacity limits. In sports arenas, you know, 20,000 people is probably too much. We need less people and all of them masked, so drop food and drinks there."

On Tuesday, Chief Medical Officer of Health Dr. Kieran Moore said he would be making recommendations to Premier Doug Ford’s cabinet on potential measures that could help slow the spread of the Omicron variant.

"There will be a discussion in the next coming days about what additional measures we need, if any, to best protect Ontarians against Omicron," Moore said. "Further news will be announced later this week."

He said capacity limits are being reviewed by his team, and options will be presented to the Ford government on things like maximum group sizes for gatherings and best practices in schools.

"We are planning to best protect our healthcare system," Moore said. "We're taking nothing for granted with this rapidly spreading virus."