In this May 25, 2020, file photo, a lab technician extracts a portion of a COVID-19 vaccine candidate during testing at the Chula Vaccine Research Center, run by Chulalongkorn University in Bangkok, Thailand. THE CANADIAN PRESS/AP-Sakchai Lalit

How many Canadians will need to get vaccinated against COVID-19? Officials aren’t sure

Canada has secured contracts for four potential vaccines

Although Canada has secured four contracts for more 190 million doses of potential COVID-19 vaccines, health officials aren’t sure how many people will need to receive it.

Deputy public health officer Dr. Howard Njoo said Tuesday (Sept. 1) that the level of vaccination to achieve community, or herd, protection varies by the disease.

“That’s still to be determined because the science is not clear on that yet,” Njoo said.

“For a very contagious disease like measles the vaccine uptake needs to be much higher to determine that level of community protection. We don’t know that yet for COVID-19.”

There are currently at least 128,948 total test positive cases of the virus in Canada, with more than 9,100 deaths.

For measles, the Canadian government has a goal of 95 per cent vaccination by 2025. According to John Hopkins University, early estimates of the virus’s infectiousness point to at least 60 to 70 per cent of the population needing to be vaccinated to achieve herd protection. A recent poll suggests that about 14 per cent of Canadians will not get the vaccine altogether, while nearly one-third will adopt a “wait and see” approach.

It’s also unclear how effective an eventual vaccine will be.

“International consensus is that we should at least look at vaccines that are around the 50 per cent vaccine efficacy mark,” chief public health officer Dr. Theresa Tam said, echoing similar statements from other public health researchers.

“This means that an individual who was vaccinated would be 50 per cent less likely to get COVID disease—or whatever the particular endpoint is that’s measured in the trial—than individuals that weren’t vaccinated,” said Dr. Ruth Karron, who leads the Center for Immunization Research at the Johns Hopkins Bloomberg School of Public Health.

But Canadian health officials were sure on one point; going for a herd immunity approach by letting the disease run through the population was not effective. Tam called it an “extremely difficult strategy” because of the potential for exponential growth that could overwhelm health-care systems.

“What we do know that even in the most [COVID-19] affected parts of the world, the level of population immunity seems quite low, so getting high enough vaccine uptake is going to be quite important,” Tam said.

Currently, Canada has agreements with Johnson & Johnson, Novavax, Pfizer and Moderna, if any of the four companies develop an effective vaccine. Any vaccine will have to be approved by Health Canada before Canadians can get it.

READ MORE: Canada signs deals with two suppliers for potential COVID-19 vaccines

READ MORE: 30% of British Columbians would ‘wait and see’ before taking COVID vaccine: poll


@katslepian

katya.slepian@bpdigital.ca

Like us on Facebook and follow us on Twitter.

Want to support local journalism during the pandemic? Make a donation here.

Coronavirusvaccines

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

“My world exploded,” says Bentley-area farmer who’s swather was struck by a motorist

Dennis Duncan was a mile from home when his swather was struck by another travelling at high speeds

Man sentenced to 7 years for gas-and-dash death of Alberta gas station owner

Ki Yun Jo was killed after Mitchell Sydlowski sped off in a stolen cube van without paying for $198 of fuel

New owners of Sylvan Lake Canadian Tire looking to be big part of the community

Randy and Alison Patton are the new owners of Sylvan Lake Canadian Tire

COVID-19: Central zone cases down to 32 Wednesday

No active cases in some central Alberta communities

Notley to stay on as Alberta NDP leader for 2023 provincial election

The NDP took almost all of Edmonton but few seats outside of the city

Young Canadians have curtailed vaping during pandemic, survey finds

The survey funded by Heart & Stroke also found the decrease in vaping frequency is most notable in British Columbia and Ontario

B.C., Alberta sending nearly 300 fire personnel by Friday to help battle wildfires in Oregon

Some 230 firefighters, most from British Columbia but including a number from Alberta, will be deployed Friday

Death of mother grizzly a ‘big loss’ for bear population in Banff park: experts

The bear, known as No. 143, spent most of her time in the backcountry of Banff

U.S.-Canadian border closure reportedly could extend through November

The border between the two countries has been closed to non-essential travel since March 21

Threat of fall federal election eases as COVID-19 cases continue to rise

Congeniality emerged as fears of second wave of COVID-19 were heightened after another case increase

Intoxicated male arrested by Ponoka RCMP passes away after fall

Incident remains under investigation by ASIRT

Breton RCMP activate Search and Rescue to locate four overdue adults

Four adults found safely near the North Saskatchewan River.

Most Read