This is an excerpt from Second Opinion, a weekly roundup of health and medical science news emailed to subscribers every Saturday morning. If you haven’t subscribed yet, you can do that by clicking here.
New Canadian data suggests the bold strategy to delay and mix second doses of COVID-19 vaccines led to strong protection from infection, hospitalization and death — even against the highly contagious delta variant — that could provide lessons for the world.
Preliminary data from researchers at the British Columbia Centre for Disease Control (BCCDC) and the Quebec National Institute of Public Health (INSPQ) shows the decision to vaccinate more Canadians sooner by delaying second shots by up to four months saved lives.
The researchers excluded long-term care residents from the data, who are generally at increased risk of hospitalization and death from COVID-19, in order to get a better sense of vaccine effectiveness in the general population — and the results were exceptional.
The analysis of close to 250,000 people in B.C. from May 30 to Sept. 11 found two doses of any of the three available COVID-19 vaccines in Canada were close to 95 per cent effective against hospitalization — regardless of the approved vaccination combination.
That means for every 100 unvaccinated people severely ill in Canadian hospitals, 95 of them could have been prevented by receiving two doses of either the AstraZeneca-Oxford, Pfizer-BioNTech and Moderna vaccines, or some combination of the three.
Dr. Danuta Skowronski with the B.C. Centre for Disease Control laid the groundwork for the decision to hold back second doses and says the early vaccine effectiveness data is extremely encouraging. (Harman/CBC)
Dr. Danuta Skowronski, a vaccine effectiveness expert and epidemiology lead at the BCCDC whose research laid the groundwork for the decision to hold back second doses based on the “fundamental principles of vaccinology,” says the early data is extremely encouraging.
“We were very pleased to see during the period when the delta variant was not just circulating, but predominating, that we had such high protection nonetheless against both infection and hospitalization,” the lead researcher on the analysis told CBC News.
“Protection was even stronger when the interval between the first and the second doses was more than six weeks apart.”
In fact, the research showed that protection against COVID-19 infection from two doses of the Pfizer vaccine rose dramatically when the first and second shots were spread out — from 82 per cent after three or four weeks, to 93 per cent after four months.
“For those who received the AstraZeneca vaccine as their first dose, their protection against any infection was lower than for mRNA vaccine recipients, but they had comparable protection against hospitalization and that’s the main goal,” she said.
“But for those who received a first dose of AstraZeneca and a second dose as an mRNA vaccine, their protection was as good as those who had received two mRNA vaccines. So that’s also a really important finding from this analysis.”
While the work is still being finalized and has not yet been submitted as a pre-print or undergone peer review, the researchers felt it’s important to get their early data out now to inform the public and policymakers here and abroad about the positive results.
“The mix-and-match schedules are protecting well, and my preference would be that those countries who don’t recognize that get to see our data as soon as possible,” she said, adding that the findings were sent to U.S. officials for review of international travel policies.
“My hope is that when they see the evidence that they will change those policies, which are frankly inconsistent with the science.”
Quebec data backs up findings from B.C.
In Quebec, thousands of kilometres away and with a different population, demographic makeup and early vaccine rollout approach — the results of a twin study that will be published alongside the B.C. data were astonishingly similar.
Of the 181 people who died from COVID-19 from May 30 to Sept. 11 in Quebec, just three were fully vaccinated. Researchers say that corresponds to a vaccine effectiveness against death upwards of 97 per cent based on a population analysis of nearly 1.3 million people.
Similar to the B.C. data, the Quebec research also showed more than 92 per cent protection from hospitalizations — with Pfizer, Moderna or AstraZeneca vaccines — against all circulating coronavirus variants of concern in Canada at that time, including delta.
“The takeaway is whatever vaccine people had, if they got two doses they should consider that they are very well protected against severe COVID-19,” said Dr. Gaston De Serres, an epidemiologist at the INSPQ. “That’s the main message.”
The analysis found Pfizer and Moderna vaccines were 90 per cent effective at preventing COVID-19 infections — either asymptomatic, symptomatic, or those needing hospital care — a protection rate equal to those with an AstraZeneca and mRNA vaccine combination.
For people who received two doses of AstraZeneca, the research suggests a slightly lower level of protection from infection — but one that is still remarkably high at 82 per cent.
The research showed that protection against COVID-19 infection from two doses of the Pfizer vaccine rose dramatically when the first and second shots were spread out. (Darryl Dyck/The Canadian Press)
De Serres says the National Advisory Committee on Immunization (NACI) and the Quebec Immunization Committee (CIQ) are looking at whether additional doses may be needed for that group, but says it’s “not as pressing” given the strong protection from hospitalization.
“For the time being, just stay put. If there is a recommendation for you to get an additional RNA dose you’ll know in time,” De Serres said. “But feel that what you’ve got is still a very good regimen to protect you against what we fear most — which is severe COVID-19.”
The NACI recommendation in March to delay second doses of all three COVID-19 vaccines by up to four months was not without controversy at the time, and no doubt led to confusion among many Canadians about whether they were adequately protected.
Canada’s Chief Science Adviser Mona Nemer said in early March that the strategy amounted to a “population level experiment,” while at the same time health officials tried to reassure the public that the approach was safe and effective.
Deepta Bhattacharya, an immunologist at the University of Arizona who was not involved in the study, says the results are “very encouraging” and provide evidence of “improved real world protection” from delaying second doses.
But he admits even he was initially skeptical.
“I was uneasy about it in large part because I just wasn’t sure how well the protection would hold up in the interim,” he said. “Obviously it turned out well … but it was risky, and that gamble paid off.”
Bhattacharya says the Canadian data now provides real world evidence that vaccinated people produce more antibodies if their second shot is delayed, and the quality of those antibodies may actually improve — which could explain the better protection against delta.
“What I’m really wondering now going forward is whether the recommendations are going to fundamentally change as to when we should get that second shot,” he said, referring to other countries around the world. “I wish I’d gotten mine later now in retrospect.”
Keeping ‘eye on the prize’ means avoiding hospitalization
The data also has implications on whether average Canadians need booster shots, particularly given that emerging real world data in other countries like the U.S., Israel and Qatar show evidence of waning immunity that has prompted the rollout of third doses.
But experts caution that while countries reporting diminished vaccine effectiveness against COVID-19 infection may be making headlines, the more important factor is that the studies largely show the vaccines have prolonged protection against severe COVID-19 — meaning hospitalization and death.
“We really should keep our eyes on the prize, which is preserving healthcare system capacity and preventing unnecessary suffering,” said Skowronski. “We’re not going to prevent every case of COVID-19. Our goal was never to prevent the sniffles. Our goal was to prevent serious outcomes.”
Still, the B.C. and Quebec data showed “no signs” of waning immunity in the general population four months after the second mRNA dose and strong protection against infection of more than 80 to 90 per cent maintained. The analysis doesn’t go beyond five months, but the researchers will continue monitoring vaccine effectiveness.
“We should be reassured that our vaccine effectiveness from this calculation, from what I’ve seen, will be robust with its protection,” said Alyson Kelvin, an assistant professor at Dalhousie University and virologist at the Canadian Center for Vaccinology and the Vaccine and Infectious Disease Organization in Saskatoon who was not involved in the research.
“We must continue to have public health measures in place as well as expect at some point we might need a booster, but data like this will inform when we do and right now it’s suggesting that we don’t need it yet — but we have to keep vigilant.”
WATCH | Canada recommends COVID-19 booster shots for long-term care residents:
NACI recommends COVID-19 booster shots for seniors in long-term care
11 days ago
Amid a global debate over COVID-19 vaccine boosters, the National Advisory Committee on Immunization is recommending third doses for Canada’s most vulnerable, especially seniors in long-term care homes. 1:58
Skowronski says that while she supports giving long-term care residents and immunocompromised people third doses of COVID-19 vaccines to increase their protection based on emerging data, including from Canada, there isn’t enough evidence yet for average Canadians.
Until then, she says Canadians should feel well protected against severe outcomes from COVID-19 in the delta-driven fourth wave if they’re fully vaccinated with any of the approved vaccine combinations in Canada.
“We’re going to have to learn to live with SARS-CoV-2, including in it’s very many future iterations,” she said.
“But so long as we can prevent severe outcomes and maintain healthcare system capacity, we can come to a kind of a mutual understanding with this virus.”
BUFFALO, N.Y. (AP) — Hearing the familiar sounds of clacking sticks and pucks banging off the boards and glass while watching Columbus Blue Jackets prospects from the stands of a cold rink on a warm late-summer afternoon was not enough to wash away the lingering residuals of grief for Don Waddell on Saturday.
That, the Blue Jackets’ general manager acknowledged, will take more time than anyone can guess — weeks, months, perhaps an entire season and beyond.
What mattered is how spending the weekend attending the Sabres Prospects Challenge represented a start to what Waddell called among the first steps in refocusing on hockey and the future in the aftermath of the deaths of Columbus star Johnny Gaudreau and his brother, Matthew, who were struck by a suspected drunken driver while riding bicycles on Aug 29.
“We got to play hockey,” Waddell said. “We’re not going to forget about Johnny and his family, the Gaudreau family.”
“Everybody knows that Johnny wants them to play hockey,” Waddell said. “And everybody’s rallying around that.”
The resumption of hockey in Columbus began last week, when most Blue Jackets players returned to their facility to be together and lean on each other at the urging of Waddell and team captain Boone Jenner. And it will continue on Thursday, when the team opens training camp, exactly three weeks since the Gaudreaus were killed.
“Tragic. Senseless. But now we got to focus on trying to get our team ready to play hockey this year,” Waddell said. “We all mourn and heal differently, but I think as a team being together like that is going to be critical for them to get moving forward.”
Waddell was general manager of the then-Atlanta Thrashers in 2003 when Dany Heatley lost control of his car and struck a wall, with the crash killing passenger and teammate Dan Snyder. In 2021, Blue Jackets goalie Matiss Kivlenieks died during a July Fourth fireworks accident.
Waddell placed the emphasis on himself and coach Dean Evason — both newcomers to Columbus this offseason — to guide the team through what will be an emotional season.
“Now, do I think there’s going to be some dark days? I won’t be surprised,” Waddell said.
Reminders of the Gaudreaus’ deaths remain apparent, and reflected in Buffalo on Friday night. A moment of silence was held in tribute to the brothers before the opening faceoff of a game between the Blue Jackets and Sabres.
Afterward, Columbus prospect Gavin Brindley recalled the times he spent with Johnny Gaudreau in Columbus and as teammates representing the United States at the world hockey championships in the Czech Republic in May.
“He was one of the biggest mentors for me at the world championships,” Brindley said. “I couldn’t tell you how many times we hung out with Meredith, pictures on my phone. It’s just so hard to look back and see that kind of stuff.”
The NHL and NHL Players’ Association are providing the Blue Jackets help in the form of grief counseling, crowd security at vigils and addressing hockey issues, such as potentially altering the league’s salary cap rules to provide Columbus relief from having to reach the NHL minimum payroll because of the void left by Gaudreau’s contract.
“The Blue Jackets, I don’t think anybody’s focused from an organizational standpoint, from a hockey standpoint as to what comes next, because I think everybody’s still in shock,” NHL Commissioner Gary Bettman told The Associated Press last week. “I don’t think anybody’s focused right now other than on the grieving part, which is understandable.”
Much of the burden has fallen to Waddell, who has been in discussions with the NHL and the NHLPA and dealing with outreach programs with the Blue Jackets’ partner OhioHealth, while also overseeing preparations for training camp and gauging his prospects in Buffalo.
There’s also his roster to attend to, which he said has two openings at forward, one involving Justin Danforth, who may miss the start of the season because of a wrist injury. Waddell didn’t have to mention the second opening.
Tiring and emotional as it’s been, Waddell found comfort being in his element, a rink, and looking ahead to the start of training camp.
“The guys are in really good shape. We’ve done a lot of testing already and they’re eager to get going,” Waddell said. “We have a reason to play for. And we’ll make the best of it.”
The Blue Jackets later Sunday signed veteran winger James van Riemsdyk to a one-year contract worth $900,000.
“James van Riemsdyk has been a very consistent, productive player throughout his career,” Waddell said. “Bringing him to Columbus will not only provide depth to our group up front, but also valuable leadership and another veteran presence in our dressing room.”
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AP Hockey Writer Stephen Whyno in New York contributed to this report.
PARIS (AP) — Paris Saint-Germain defender Nuno Mendes was the target of abusive and racist comments on social media after a French league game.
The club condemned the abuse and expressed its “full support” Sunday for the Portugal left back, who was targeted following PSG’s 3-1 win against Brest on Saturday.
Mendes, who is Black, shared on his Instagram account a racist message he received.
During the match, Mendes brought down Ludovic Ajorque in the box for a penalty that Romain Del Castillo converted to give Brest the lead.
“Paris Saint-Germain doesn’t tolerate racism, antisemitism or any other form of discrimination,” the club said. “The racial insults directed at Nuno Mendes are totally unacceptable … we are working with the relevant authorities and associations to ensure those responsible are held accountable for their actions.”
MONTREAL – Tadej Pogacar was so dominant on Sunday, Canada’s Michael Woods called it a race for second.
Pogacar, a three-time Tour de France champion from Slovenia, pedalled to a resounding victory at the Grand Prix Cycliste de Montreal.
The UAE Team Emirates leader crossed the finish line 24 seconds ahead of Spain’s Pello Bilbao of Bahrain — Victorious to win the demanding 209.1-kilometre race on a sunny, 28 C day in Montreal. France’s Julian Alaphilippe of Soudal Quick-Step was third.
“He’s the greatest rider of all time, he’s a formidable opponent,” said Woods, who finished 45 seconds behind the leader in eighth. “If you’re not at your very, very best, then you can forget racing with him, and today was kind of representative of that.
“He’s at such a different level that if you follow him, it can be lights out.”
Pogacar slowed down before the last turn to celebrate with the crowd, high-five fans on Avenue du Parc and cruise past the finish line with his arms in the air after more than five hours on the bike.
The 25-year-old joined Belgium’s Greg Van Avermaet as the only multi-time winners in Montreal after claiming the race in 2022. He also redeemed a seventh-place finish at the Quebec City Grand Prix on Friday.
“I was disappointed, because I had such good legs that I didn’t do better than seventh,” Pogacar said. “To bounce back after seventh to victory here, it’s just an incredible feeling.”
It’s Pogacar’s latest win in a dominant year that includes victories at the Tour de France and Giro d’Italia.
Ottawa’s Woods (Israel Premier-Tech) tied a career-best in front of the home crowd in Montreal, but hoped for more after claiming a stage at the Spanish Vuelta two weeks ago.
“I wanted a better result,” the 37-year-old rider said. “My goal was a podium, but at the same time I’m happy with the performance. In bike racing, you can’t always get the result you want and I felt like I raced really well, I animated the race, I felt like I was up there.”
Pogacar completed the 17 climbs up and down Mount Royal near downtown in five hours 28 minutes 15 seconds.
He made his move with 23.3 kilometres to go, leaving the peloton in his dust as he pedalled into the lead — one he never relinquished.
Bilbao, Alaphilippe, Alex Aranburu (Movistar Team) and Bart Lemmen (Visma–Lease) chased in a group behind him, with Bilbao ultimately separating himself from the pack. But he never came close to catching Pogacar, who built a 35-second lead with one lap left to go.
“It was still a really hard race today, but the team was on point,” Pogacar said. “We did really how we planned, and the race situation was good for us. We make it hard in the last final laps, and they set me up for a (takeover) two laps to go, and it was all perfect.”
Ottawa’s Derek Gee, who placed ninth in this year’s Tour de France, finished 48th in Montreal, and called it a “hard day” in the heat.
“I think everyone knows when you see Tadej on the start line that it’s just going to be full gas,” Gee said.
Israel Premier-Tech teammate Hugo Houle of Sainte-Perpétue, Que., was 51st.
Houle said he heard Pogacar inform his teammates on the radio that he was ready to attack with two laps left in the race.
“I said then, well, clearly it’s over for me,” Houle said. “You see, cycling isn’t that complicated.”
Australia’s Michael Matthews won the Quebec City GP for a record third time on Friday, but did not finish in Montreal. The two races are the only North American events on the UCI World Tour.
Michael Leonard of Oakville, Ont., and Gil Gelders and Dries De Bondt of Belgium broke away from the peloton during the second lap. Leonard led the majority of the race before losing pace with 45 kilometres to go.
Only 89 of 169 riders from 24 teams — including the Canadian national team — completed the gruelling race that features 4,573 metres in total altitude.
Next up, the riders will head to the world championships in Zurich, Switzerland from Sept. 21 to 29.
Pogacar will try to join Eddy Merckx (1974) and Stephen Roche (1987) as the only men to win three major titles in a season — known as the Triple Crown.
“Today gave me a lot of confidence, motivation,” Pogacar said. “I think we are ready for world championships.”
This report by The Canadian Press was first published Sept. 15, 2024.
