A vial of some of the first 500,000 of the two million AstraZeneca COVID-19 vaccine doses that Canada has secured through a deal with the Serum Institute of India in partnership with Verity Pharma at a facility in Milton, Ont., on Wednesday, March 3, 2021. THE CANADIAN PRESS/Carlos Osorio - POOL

A vial of some of the first 500,000 of the two million AstraZeneca COVID-19 vaccine doses that Canada has secured through a deal with the Serum Institute of India in partnership with Verity Pharma at a facility in Milton, Ont., on Wednesday, March 3, 2021. THE CANADIAN PRESS/Carlos Osorio - POOL

Federal panel recommends 4-month gap between COVID vaccine doses due to limited supply

The recommendation applies to all COVID-19 vaccines currently approved in Canada

The National Advisory Committee on Immunization (NACI) is supporting B.C.’s decision to delay the second doses of COVID-19 vaccines by up to four months.

“NACI recommends that in the context of limited COVID-19 vaccine supply jurisdictions should maximize the number of individuals benefiting from the first dose of vaccine by extending the second dose of COVID-19 vaccine up to four months after the first,” the committee said in a decision published Wednesday (March 3).

The recommendation applies to all COVID-19 vaccines currently approved in Canada; Pfizer-BioNTech, Moderna and the newly approved AstroZeneca vaccine.

B.C. announced the decision to delay the second booster shot for four months on Monday, which health officials said could mean that all adults in the province could have their first dose by July.

READ MORE: Most B.C. adults could get their first COVID vaccine shot by July: health officials

Both provincial health officer Dr. Bonnie Henry and NACI said that its rationale was based on both the current available vaccine supply and data from other countries.

A study published by the University of Cambridge in the U.K., which has not yet been peer-reviewed, suggests that a single dose of the Pfizer-BioNTech vaccine can reduce the number of asymptomatic COVID-19 infections by 75 per cent.

In Israel, researchers studied the effects of a single dose of the same vaccine and published their findings in The Lancet medical journal, concluding that it was 85 per cent effective against symptomatic COVID-19 infections.

Also in The Lancet, a U.K. study found that the Oxford-AstraZeneca vaccine is 81 per cent effective when its second dose is given three months after the first, compared with 55 per cent efficacy after six weeks.

The national advisory committee noted that since the COVID-19 vaccines are still new, its unknown how long the protection of one or both doses lasts for.

“Experience with other multi-dose vaccines after a single dose suggests persistent protection could last for six months or longer in adolescents and adults,” NACI said in its statement. “Longer-term follow-up of clinical trial participants and those receiving vaccination in public programs will assist in determining the duration of protection following both one and two doses of vaccination.”

The national advisory committee added that it’s unknown how a delayed booster shot regime will affect the spread of variants of concern, including the U.K. and South African ones. However, NACI notes that there is “currently no evidence that an extended interval between doses will either increase or decrease the emergence of variants of concern.”

The committee noted that all three currently approved vaccines have shown “promising early result” against the U.K. variant B.1.1.7.

READ MORE: COVID-19 wage and rent subsidies, lockdown support to be extended until June

– with files from The Canadian Press


@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

A police car at the scene of a child’s death Friday, April 9, at the Falcon Nest Motel in Duncan. (Kevin Rothbauer/Citizen)
RCMP investigating child’s death at Duncan’s Falcon Nest Motel

First responders responded to a call about an unresponsive child at the… Continue reading

Town of Lake Cowichan looking to form tourism and housing committees

Decision not related to the Lake Cowichan Visitor Information Centre closure

“Representing the school district, legion, and Kaatza Station Museum left to right are Georgie Clark of the museum, Wilma Rowbottom of School District #66 and Ernie Spencer, representing the Legion. The museum and Legion, along with the Village will each take a piece of the old wood shop.” (The Lake News)
Lake Flashback: Soapboxes, woodshop split, taxes down

Remember these stories from Lake Cowichan?

Tim Schewe
Drivesmart column: Rules around bicycle lanes

The lane is often painted green to distinguish it from lanes intended for motor vehicles.

Robert’s column
Robert Barron column: New hospital shouldn’t charge for parking

Paying a parking meter is the last thing people visiting a hospital should have to worry about.

B.C. Health Minister Adrian Dix and Premier John Horgan describe vaccine rollout at the legislature, March 29, 2021. (B.C. government)
1,262 more COVID-19 infections in B.C. Friday, 9,574 active cases

Province’s mass vaccination reaches one million people

People walk past the Olympic rings in Whistler, B.C., Friday, May 15, 2020. Whistler which is a travel destination for tourists around the world is seeing the effects of travel bans due to COVID-19. THE CANADIAN PRESS/Jonathan Hayward
Adults living, working in Whistler, B.C., eligible for COVID-19 vaccine on Monday

The move comes as the province deals with a rush of COVID-19 and variant cases in the community

RCMP display some of the fish seized from three suspects who pleaded guilty to violating the Fisheries Act in 2019, in this undated handout photo. THE CANADIAN PRESS/HO - RCMP
3 banned from fishing, holding licences after overfishing violations near Vancouver Island

Mounties seized the group’s 30-foot fishing vessel and all equipment on board at the time

B.C. Premier John Horgan responds to questions during a postelection news conference in Vancouver, on Sunday, October 25, 2020. British Columbia’s opposition Liberals and Greens acknowledge the COVID-19 pandemic has presented huge challenges for Horgan’s government, but they say Monday’s throne speech must outline a coherent plan for the province’s economic, health, social and environmental future. THE CANADIAN PRESS/Darryl Dyck
Horgan’s NDP to bring in throne speech in B.C., Opposition wants coherent plan

Farnworth said the budget will include details of government investment in communities and infrastructure

FILE - An arena worker removes the net from the ice after the Vancouver Canucks and Calgary Flames NHL hockey game was postponed due to a positive COVID-19 test result, in Vancouver, British Columbia, in this Wednesday, March 31, 2021, file photo. As vaccinations ramp up past a pace of 3 million a day in the U.S, the NHL is in a tougher spot than the other three major North American professional sports leagues because seven of 31 teams are based on Canada. (Darryl Dyck/The Canadian Press via AP, File)
Vancouver Canucks scheduled to practice Sunday, resume games April 16 after COVID outbreak

Canucks outbreak delayed the team’s season by eight games

Two-year-old Ivy McLeod, seen here on April 9, 2021 with four-year-old sister Elena and mom Vanessa, was born with limb differences. The family, including husband/dad Sean McLeod, is looking for a family puppy that also has a limb difference. (Jenna Hauck/ Chilliwack Progress)
B.C. family looking for puppy with limb difference, just like 2-year-old Ivy

Ivy McLeod born as bilateral amputee, now her family wants to find ‘companion’ puppy for her

A vehicle that was driven through the wall of a parkade at Uptown Shopping Centre and into the nearby Walmart on April 9 was removed through another hole in the wall later that night. (Photo via Saanich Police Department and Ayush Kakkar)
Vehicle launched into B.C. Walmart removed following rescue of trapped workers

Crews cut new hole in parkade wall to remove vehicle safely

Most Read