Several provinces were preparing to loosen COVID-19 restrictions on Sunday, as Canada's chief public health officer expressed optimism over vaccines ahead of the one-year anniversary of the COVID-19 crisis.

The World Health Organization declared COVID-19 a pandemic last March 11, and Chief Public Health Officer Dr. Theresa Tam said it's been a difficult 12 months marked by hardship and sacrifice.

"Yet, as the months have gone by, I have also witnessed the remarkable courage, strength, and generosity demonstrated by Canadians," she wrote in a statement.

"Through it all, it is the incredible support that Canadians have shown for one another that has impressed me the most."

Tam expressed optimism that brighter days were coming, thanks to the recent approvals of the Johnson & Johnson and Oxford-AstraZeneca vaccines.

"This week has been a very good week for Canada's COVID-19 vaccination programs," she wrote.

The anniversary comes as all provinces are expanding their mass vaccination programs and some are loosening restrictions aimed at limiting the spread of the virus.

Quebec, Ontario and New Brunswick are among the provinces preparing to lift restrictions on Monday after weeks of stable or declining cases.

A stay-at-home order in Ontario's Toronto, Peel and North Bay regions will lift on Monday, while five Quebec regions, including Quebec City, will be downgraded from red to orange on the province's colour-coded regional alert system.

All of New Brunswick will transition to the less-restrictive "yellow" alert level Sunday at midnight, meaning residents can expand their contacts from 10 to 15 people and team sports activities may resume.

Canada's two biggest cities will remain under fairly strict restrictions, however.

Toronto -- and neighbouring Peel Region -- will enter the "grey lockdown" category, which will allow more retailers to open, with restrictions, but leaves gyms, personal care services and indoor restaurant dining closed.

The greater Montreal region remains a red zone, which means an 8 p.m. curfew is still in effect.

Tam said the addition of the two new vaccines will help Canadians get immunized faster and help ease the worries surrounding supply disruptions or setbacks.

In a long message, Tam said it is not that it is @not possible to directly compare the efficacy of different vaccines to one another.

"Each vaccine was studied in a separate trial conducted at different times, using different populations and conditions," she wrote.

She said the single-shot Johnson & Johnson vaccine, manufactured by Janssen, was shown to be 66 per cent effective overall in preventing moderate to severe COVID-19, while the AstraZeneca vaccine was found to have an efficacy of 62 per cent in generally preventing "symptomatic COVID-19."

Both vaccines, she said, were found to protect against severe disease, meaning that those who got COVID-19 after the shot were much less likely to get seriously ill.

Currently, Canada's National Advisory Committee on Immunization does not recommend that the AstraZeneca vaccine be given to those aged 65 or over due to limited data, but Tam stressed that the recommendations could change.

She noted both the new vaccines are easier to transport than those produced by Pfizer-BioNTech and Moderna, which require freezer storage.

With Canada set to receive more than 900,000 COVID-19 doses of the Pfizer and Moderna vaccines this week, many provinces are ramping up their vaccination campaigns.

Health authorities across British Columbia will start booking COVID-19 vaccination appointments Monday for people 90 years old and older and Indigenous residents over the age of 65.

Quebec, which has been booking vaccine appointments for seniors 70 or 80 and over depending on the region, will speed up the pace this week as more mass vaccination centres open across the province after focusing mainly on hard-hit Montreal last week.

Ontario reported administering 30,192 doses of COVID-19 vaccine on Saturday, for a total of 890,604 doses handed out so far.

Saskatchewan, meanwhile, reported 116 more cases and two more deaths due to COVID-19, including a person who was under 20 years old.

The government said it would receive more than 14,000 doses of Pfizer-BioNTech vaccine this week, which will be sent to five different parts of the province.

This report by The Canadian Press was first published March 7, 2021