Dr. Bonnie Henry talks about phase two in B.C.’s COVID-19 immunization plan as Premier John Horgan and Minister Arian Dix look on during a press conference at Legislature in Victoria, B.C., on Monday, March 1, 2021. THE CANADIAN PRESS/Chad Hipolito

Dr. Bonnie Henry talks about phase two in B.C.’s COVID-19 immunization plan as Premier John Horgan and Minister Arian Dix look on during a press conference at Legislature in Victoria, B.C., on Monday, March 1, 2021. THE CANADIAN PRESS/Chad Hipolito

Vaccines: B.C. pushes ahead with delayed second doses as Ontario waits for national guidance

Dr. Bonnie Henry said she expects the national immunization committee to align with the province’s decision

Ontario is waiting for a recommendation from the National Advisory Committee on Immunization before delaying second doses of COVID-19 vaccines, while British Columbia is pushing ahead with its plan to extend the interval to four months.

A researcher whose work underpinned B.C.’s decision said Tuesday that the change was based on strong data. Dr. Danuta Skowronski, epidemiology lead of influenza and emerging respiratory pathogens at the B.C. Centre for Disease Control, said Pfizer-BioNTech underestimated the efficacy of the first dose of its own vaccine in its submissions to the U.S. Food and Drug Administration.

Skowronski said the company included data from the first two weeks after trial participants received the shot, which is a time when vaccines typically aren’t effective. When she and her colleagues adjusted the data, they made a surprising discovery.

“We took that into account and showed that the vaccine efficacy was not 52 per cent, it was actually 92 per cent. That was actually very similar, that first-dose efficacy, to what the other manufacturer, Moderna, had actually itself correctly analyzed in its own submissions to the FDA,” she said in an interview.

Skowronski said the four-month interval is based on the basic principles of vaccine science. The protection from a first dose of vaccine does not suddenly disappear, it gradually wanes over time, and scientists are typically more concerned about providing a second dose too soon rather than too late, she said.

“I think if the public had a chance to hear and to understand that, they would say, ‘OK, this is not messing around. This is really managing risk in a way that maximizes protection to as many Canadians as possible.’”

She said the province’s decision was backed up by data from Quebec, the United Kingdom and Israel, and comes at a time when B.C. residents are experiencing severe social and economic effects from isolation during the pandemic.

Skowronski added that the B.C. Centre for Disease Control also examined the effects of a single dose on long-term care residents and health-care workers in the province and found that it reduced the risk of the virus by 80 per cent within two to three weeks.

Provincial health officer Dr. Bonnie Henry has said she expects a statement from the national immunization committee aligning with the province’s decision, while Ontario Health Minister Christine Elliott said Tuesday she wanted to wait for such a recommendation.

She said extending the interval between doses would allow the province to get some level of protection to more people.

“This would be a considerable change,” she said.

“With the variants of concern out there, this could make a significant difference for Ontario in reducing hospitalizations and deaths. So, we are anxiously awaiting NACI’s review of this to determine what they have to say in their recommendations.”

Dr. Shelley Deeks, vice-chair of the national committee, said in an email the group is expected to issue a statement on extending the dose interval on Wednesday, but she did not confirm it would align with B.C.’s plan.

Alberto Martin, a University of Toronto immunology professor, said his understanding of a published Pfizer-BioNTech clinical trial was that the first dose provided 60 per cent protection and the second dose provided 95 per cent protection.

He said there is “obviously some concern” about B.C.’s plan because he is not aware of any clinical trial that examined a four-month gap between doses.

“There might be a risk that you’re not going to achieve that 95 per cent protection that the Pfizer-BioNTech vaccine can achieve with two doses separated by a few weeks apart,” he said.

However, he said difficult times — when the vaccine supply is so limited — require drastic measures.

“I think what they’re trying to do is immunize as many people as possible, get partial protection in the population and then hope for the best that the second dose that comes in four months later will boost the immune response enough to achieve that 95 per cent protection,” he said.

“It’s a difficult decision to make. I don’t know whether I’d like to be in that position, but I think it’s understandable why they’re doing this.”

Coronavirus

Just Posted

A grant from the Okanagan Basin Water Board has allowed the historic O’Keefe Ranch in Spallumcheen to construct and complete its rain gardens project. (O’Keefe Ranch photo)
Spallumcheen ranch protects ecosystem with water grant

Historic O’Keefe Ranch receives $20,000 to construct and complete rain gardens project

Michelle Jacobs receives her first dose of the COVID-19 vaccine at the Coast Capri Hotel on April 28, 2021. The pop-up clinic was hosted by the First Nations Health Authority. (Aaron Hemens/Capital News)
126 new cases of COVID-19 in Interior Health over the weekend

There are 22 individuals hospitalized due to the virus, and 13 in intensive care

(File photo)
Repeated cougar sighting on Okanagan Rail Trail

Plenty of bear sightings around the valley too

Vernon local Ryan Lazar – who specializes in 2D background design and 3D animation – is ready to start his career after a tough yet rewarding two years of studies. (Contributed)
Okanagan College students get animated at graduation

‘The pandemic has resulted in more video consumption and the animation industry is so hot right now because of it’

An e-scooter and a car bumper make for a narrow passthrough on a sidewalk out front of the Kelowna Law Courts on Wednesday, April 28. (Michael Rodriguez/Black Press)
E-scooters ready to roll in Vernon

Final bylaw changes in place to allow personal use and for companies to operate a rental program

WildSafeBC is reminding residents to keep manage wildlife attractants on their property. (WildSafeBC Central Okanagan)
WildSafeBC reminds residents to manage attractants as bears spotted in Okanagan

The most prominent reminder is to keep garbage secured indoors until collection day

Barriere RCMP nabbed two suspects who were allegedly breaking into cabins in McLure. (File photo)
Thieves nabbed by Barriere Mounties during McLure break-ins

Police Service Dog Kody instrumental in making the arrest

Cannabis bought in British Columbia (Ashley Wadhwani/Black Press Media)
Is it time to start thinking about greener ways to package cannabis?

Packaging suppliers are still figuring eco-friendly and affordable packaging options that fit the mandates of Cannabis Regulations

B.C. Health Minister Adrian Dix and provincial health officer Dr. Bonnie Henry update the province’s COVID-19 vaccine program, May 10, 2021. (B.C. government)
B.C.’s COVID-19 infection rate stays below 500 a day over weekend

14 more deaths, down to 350 in hospital as of Monday

Join Black Press Media and Do Some Good
Join Black Press Media and Do Some Good

Pay it Forward program supports local businesses in their community giving

Royal Bay Secondary School’s rainbow crosswalk was vandalized shortly after being painted but by Monday, coincidentally the International Day Against Homophobia, Transphobia and Biphobia, the crosswalk had been cleaned up and students had surrounded it with chalk messages of support and celebration. (Zoe Ducklow/News Staff)
B.C. high’s school’s pride crosswalk restored following ‘hateful’ graffiti attack

Hate terms, racial slur, phallic images spray-painted at Greater Victoria high school

RCMP vest
Penticton beach brawl results in one arrest but no charges

People took to social media after a fight broke out at the fire pits at Okanagan Lake Saturday

Terrance Mack would have celebrated his 34th birthday on May 13, 2021. Mack’s family has identified him as the victim of a homicide in an apartment on Third Avenue in Port Alberni sometime in April. (SUBMITTED PHOTO)
Family identifies Ucluelet man as victim of Vancouver Island homicide

Terrance Mack being remembered as ‘kind, gentle’ man

A single motorcycle parked outside of the Kelowna Hells Angels clubhouse at 837 Ellis Street on July 9, 2020. (Michael Rodriguez - Capital News)
Kelowna Hells Angels prospect sentenced to 9 months in jail for aggravated assault

Colin Michael Bayley pleaded guilty to the downtown Kelowna assault earlier this month

Most Read