Canada needs to jump-start a stalled first-dose campaign to avoid a fourth wave, experts say

Canada has gone from a vaccine laggard to a world leader in COVID-19 immunizations in just a few months' time thanks toan ambitious vaccination campaign that has so far blunted the spread of the much more virulent delta variant.

More than 79 per cent of those eligible for a shot have received at least one dose of a COVID-19 vaccine.

While that's a high number, it suggests there are still more than six million people over the age of 12 who have chosen to forgo a shot altogether, or wait for a later date.

The number of unvaccinated Canadians is roughly equivalent to everyone living in the Calgary, Edmonton, Ottawa, Winnipeg and Quebec City metropolitan areas combined.

Experts agree more people need to get the shotto avoidanother pandemicresurgence withdevastating consequences. The challenge now involves easing access and convincing the hesitant among us to roll up their sleeves,experts say.

After a blitz in April and May, the number of new first doses being administered has stalled at well under 100,000 daily since June 16. That means it would take months more to immunize the remaining holdouts at the current pace.

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Dr. Theresa Tam, Canada's chief public health officer, said recently the vaccination campaign has produced impressive results. But it's not enough, she said,to simplyhit the government's early target of 75 per cent of the eligible population with a single shot whenthe much more contagious delta variant which appears to betwice as virulent as other strains is circulating widely.

Dr. Anthony Fauci, the doctor leading the COVID-19 fight in the U.S., was among those who first suggested "herd immunity" against the virus would develop at a 75 to 80 per cent vaccination rate. The new variants may have rendered that targetobsolete.

"Should we aim for higher? Yes, I think we should. Shoot for higher, shoot for gold, shoot for the stars. That gives us a better buffer for managing the COVID-19 situation," Tam said.

"We've got some work to do," Dr. Howard Njoo, Tam's deputy, told a press conference Thursday. "I think we could obviously do better."

WATCH: Dr. Njoo discusses COVID-19 booster shots

Deputy Chief Public Health Officer Dr. Howard Njoo discusses Covid booster shots.

3 years ago

Duration 1:59

Dr. Njoo says while research on the need for a booster shot is under way, his main focus now is on fully vaccinating Canadians.

Caroline Colijn is a mathematician who specializes in infectious diseases at Simon Fraser University in Burnaby, B.C.

Colijn told CBC News it's hard to pinpoint an exact vaccination rate that would make it safer to further relax pandemic-related restrictions in Canada butit should be higher than it isnow.

More shots in arms could spell the difference between a fourth pandemicwave like the crush of newcasespiling up in the U.K. and the Netherlands and no wave at all, Colijn said, citing some of the modelling she and her team of researchers have compiled.

"There is a lot of uncertainty and I don't think we have one number where we can say 'Oh, OK, it's 82 per cent, that's it, that's enough and we won't have COVID anymore,'" she said. "But we do know that 90 per cent would give us so much better protection than 80 per cent because it cuts in half the number of people who aren't protected at all."

Colijn said that at90 per cent protection, there will be both fewer cases andfewer opportunities for new mutations to emerge because there won't be as many unvaccinated vectors for the virus.

"I'm not going to say we're going to be in the clear. We don't know how much immunity will wane over time,hopefully it won't. But I think it would put us in a really great position," she said. "We can say with high confidence we'll be in a much, much better position at 90 per cent. We'll cut those chains of transmission and we'll be more resilient to the arrival, spread or emergence of new variants."

Widespread infections amongmillions of unvaccinated Canadianscould be enough to overwhelm the healthcare system again. New variants also threaten to penetrate the high level of protection that the fully vaccinated currently enjoy.

"It's even more important for us to really reach a high level of vaccinations when we start to see variants that can break through that vaccination. You just need that much more vaccination to get to the same place," Colijn said.

The federal government's own modelling, released late last month, suggests hospital capacity may again reach dangerous levels in the fall and winter months if vaccine coverage is at or below 80 per cent across all age groups with the contagiousdelta variant as the dominant strain.

In the United Kingdom, where 87.6 per cent of adults have had a first shot, hospitalizations have increased to levels not seen since February, with 600daily admissions andreports of 50,000 new cases most of them of the delta variety eachday. The number of people in hospital with coronavirus could reach "quite scary"levels within weeks, England's chief medical officerChris Whittysaid Friday.

'Rural areas have had the biggest problems'

In Ontario, a province where vaccines have been relatively plentiful in most areas for weeks, vaccination coverage varies greatly by region and age.

While vaccine uptake has been extraordinarily high among older Canadians, in many jurisdictions the 18-29 age cohort has been noticeably less willing.

In the City of Ottawa, for example, well over 90 per cent of residents 70 years of age and older have had at least one shot an enviable level of coverage. As of July 14, fewer than 70 per cent of people aged 18 to 29 have had that first dose.

In rural Renfrew County, a sprawling region in eastern Ontario, the vaccination campaign has hit a wall of vaccine hesitancy.

Earlier this month, some areas in the county reported first-dose vaccination rates at just 50 per cent, according to provincial data while urban areas like Toronto and the suburbs in Peel Region had coverage rates that were some 15 to 20 points higher.

Dr. Rob Cushman, the medical officer of health for Renfrew County, told CBC News that90 to 95 per cent of the shots administered in his jurisdiction over the past three weeks have been second doses, even though just 72 per cent of the people in the area have had a first dose. (That last number is likely somewhat higher, Cushman said, because vaccinations among Canadian Forces service membershave not yet been factored into the local numbers. There's a large military basein Petawawa, Ont.)

"It's a big problem. Some of our rural areas have had the biggest problems," Cushman said. "These people who haven't been vaccinated in the 20 to 45 years of age crowd they're going to suffer the most, they're going to get it and they're going to give it to their kids. We really have to motivate them even though they're young and they may think they're invincible."

Cushman said lower vaccine rates can be explained in part by access problems for rural dwellers; he's already planning pop-up clinicsin smaller communities in the coming days. But he estimates thatas much as 10 per centof the population won't get the shot, no matter what.

"There's a real dig-in-your-heelsanti-vax crowd and you have distrust of government, libertarianism, anti-science and all these things," he said.

There's another group of people, Cushman said, who are not fiercelyopposed to getting a shot but are worried about possible side effects, suffer fromneedle-related phobias or feellingering anxiety about the pace at which these products were developed.

He said there's also a perception that, because many rural areas have been spared the high caseloads reported in some cities, Canadians in more remote areas face a lower risk of infection.

"We've done very well compared to the city and people think we're more immune," he said. "But what we're seeing now and I didn't know this even three months ago is just how high the vaccination rate needs to be to get herd immunity. It's a matter of really convincing people, and it's a hard sell, let me tell you."

Lagging vaccination rates have been reported in other rural regions.Recent polling conducted by the Saskatchewan Population Health Evaluation and Research Unit found a vaccine acceptance rate of less than 64 per cent in some parts of the province's northern and southern regions, compared to 74 to 89 per cent in urban areas like Regina and Saskatoon.

Beyond smaller pop-up clinicsdesigned to target the holdouts, Cushman is considering more personalized interventions sending public health workers door-to-door to connectwith unvaccinated homes and empowering more family doctors to give the shot.

"This is when the hard slog starts," he said.

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