EDMONTON -- It's a term you may have heard over the past year. 'Herd immunity' is often mentioned in the context of moving past the current pandemic and back into a more pre-COVID-19 sense of normalcy.

But how do we achieve it?

Medical experts agree that the safest path to herd immunity is through mass vaccinations - but a recent study suggests many Albertans may not be on board with that plan.

In a poll released by Angus Reid Institute last month, 23 per cent of Albertans surveyed said they would not get a coronavirus vaccine. Three per cent said they weren't yet sure.

Compared to a national average of about 19 per cent who say they either would not or may not get the shot, Alberta would seem to be home to a higher number of vaccine-sceptics than the rest of the country. 

'NOT TOO CONCERNED': KENNEY

During a news conference Monday, CTV News Edmonton's Bill Fortier asked Alberta's premier if he was worried about those numbers.

"I’m not too concerned about that," Premier Jason Kenney replied. "Of course, we strongly encourage everyone to get vaccinated when their time comes up."

Kenney said as the province's vaccine rollout continues, he expects those saying "no" right now will eventually change their minds.

"So people can see, as more and more folks get vaccinated, that it’s safe and that it’s effective."

But one public health policy expert is concerned.

Tim Caulfield, research director of the University of Alberta's Health Law Institute, tells CTV News Edmonton that in order to achieve herd immunity a large majority of the population will need to get the shot.

"Most will tell you that we need to get to 70, 80 per cent in order to get some degree of population protection," he said. "So 70, 80 per cent of the population needs to get vaccinated and to be honest with you, many are saying even higher.

"You know, more is better, so any degree of hesitancy is problematic."

Take into consideration the continued spread of variant strains of COVID-19 in the province and the percentage of immunized Albertans needed to achieve herd immunity might start to look like a moving target.

"With respect to herd immunity, we do know that the variants are more infectious and so we are looking right now at how we would incorporate vaccine coverage rates into our planning going forward with respect to how that informs what kind of measures we need," Alberta's chief medical officer of health Dr. Deena Hinshaw said Monday. "But we don’t yet have a firm number."

Another factor: No vaccines are currently approved for Canadians under the age of 16.

"Twenty per cent of the population says they’ll never get it. Those are pretty grim numbers," said Caulfield. "Layer on top of that…individuals that can’t get it and we get to a number that is nowhere near sufficient."

RETURN TO NORMALCY?

Caulfield says elected officials will have some difficult policy decisions to make if too few Albertans choose to get vaccinated.

"About how much we can open up, about wearing masks, about what education is going to look like, about how restaurants and stores are going to look.

"If we can get enough people vaccinated, that makes it a lot easier. That’s going to allow Alberta to open up."

Starting Wednesday, Albertans aged 50 to 64 years old will be eligible to receive the AstraZeneca vaccine if they do not have a severe chronic illness. Indigenous people from 35 to 49 years old will also be eligible in Alberta. 

The province has said every Albertan over the age of 18 who wants a vaccine will have received at least one dose by the end of June.

But the question remains: Come July, how many eligible Albertans will have chosen to get vaccinated, and will that number be high enough to achieve herd immunity in the province?

On at least one point, Tim Caulfield and Jason Kenney agree.

"People need to understand," said Kenney, "that if we want to get our lives back, to get freedom back, then we have to have as many people as possible take that vaccine."

"Let’s make this easy for the Alberta government and public health officials," said Caulfield. "Get vaccinated."

With files from CTV News Edmonton's Bill Fortier