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Single vaccine jab appears highly effective against COVID-19, experts say

A single jab of COVID-19 vaccine appears to be highly effective, which could allow better use of scarce supplies and see more people immunized, federal and Quebec health officials said Thursday.

A single jab of COVID-19 vaccine appears to be highly effective, which could allow better use of scarce supplies and see more people immunized, federal and Quebec health officials said Thursday. 

Health authorities in Ottawa said experts were looking at whether one shot of the Pfizer-BioNTech vaccine could be almost as good as the recommended two. 

Canada's deputy chief public health officer, Dr. Howard Njoo, called the data in a new Canadian-authored study compelling.

Writing in the New England Journal of Medicine, two doctors say U.S. data indicate the vaccine to be 92 per cent effective against COVID-19 two weeks after just one dose. Original data suggested a first dose offered about 52 per cent protection.

Co-author Dr. Gaston De Serres, with the Institut national de sante publique du Quebec, said preliminary data show a single dose given to health-care workers and long-term care residents in the province had been 80 per cent effective within two or three weeks.

De Serres and Dr. Danuta Skowronski, with the British Columbia Centre for Disease Control, said delaying second doses could allow more of the most vulnerable to be protected by giving them at least one shot.

To stretch its supplies, New Brunswick said residents at lower risk for severe disease will now wait up to three months for a second vaccine dose so as many others as possible can get their first.

"This is not a perfect approach but action is required," said Dr. Jennifer Russell, the province's chief medical officer of health.

Across Canada, COVID-19 has killed 21,435 people out of 834,000 infections. Almost 33,000 people are currently infected, according to federal data.

Ontario reported another 44 pandemic-related deaths to bring its total to 6,773 and Quebec saw 10 more fatalities, bringing its total to 10,268.

"It is important to remember that the vast majority of Canadians remain susceptible to COVID-19," the Public Health Agency of Canada said.

The misery inflicted by the pandemic, beyond its rising death count, was highlighted Thursday by a report showing record-setting job losses in the country's largest province last year, with young people hit hardest.

Ontario's fiscal watchdog said 355,000 jobs disappeared, while another 765,000 people had work hours cut. Youth unemployment jumped to 22 per cent.

The Canadian Labour Congress, noting many people were still out of work and facing an end to emergency benefits, called on Ottawa to provide extra weeks of aid beyond the maximum 26. Latest federal data show the Canada Recovery Benefit paid out $9.88 billion in the $500-a-week aid to more than 1.7 million people in the past four months.

Despite mounting casualties, new cases of COVID-19 have plunged in recent weeks, prompting eased restrictions in many areas.

Alberta Health Minister Tyler Shandro said it may be safe to lift more restrictions soon as the numbers trend downward. The province announced 415 new infections Thursday. 

However, Saskatchewan Premier Scott Moe issued a recommendation that residents travelling outside the province get tested twice for COVID-19 to prevent more contagious variants from taking hold there.

In British Columbia, health officials reminded residents to follow public health orders and restrictions after a rise in cases from earlier this week. The province reported 617 new cases on Thursday after recording 348 cases between Sunday and Monday.

In a joint statement, provincial health officer Dr. Bonnie Henry and Health Minister Adrian Dix said much of the uptick in cases has been in the Lower Mainland and in the province's northern region.

Ontario Premier Doug Ford said his province was considering a plea from two hot spots — Toronto and Peel Region — to stay locked down for two more weeks. 

In Newfoundland and Labrador, where a stubborn outbreak of coronavirus disease has hit the capital region, the mayor of a fly-in community expressed shock after a still unconfirmed case in his village.

Mayor Barry Andersen of Makkovik on Labrador's north coast said the case appeared to be related to medical travel to St. John's. Save for a few scattered cases, Labrador health officials have so far managed to keep the virus out of the region. 

Makkovik was one of the first places in the province to receive the Moderna vaccine and about 75 per cent of residents have received two doses.

In Manitoba, those able to receive their shots can now access proof of vaccination to carry with them. The information can be printed from a government website while the province works toward more formal vaccination cards like in British Columbia.

Quebec Premier Francois Legault, meanwhile, said his government would compensate soon-to-reopen movie theatres barred from selling popcorn and other snacks as an anti-pandemic measure. 

— With files from Mia Rabson and Jordan Press in Ottawa, Jacob Serebrin in Montreal, Sarah Smellie in St. John's, N.L., Holly McKenzie-Sutter in Toronto and Kevin Bissett in Fredericton.

This report by The Canadian Press was first published Feb. 18, 2021.

Colin Perkel, The Canadian Press