VICTORIA -- British Columbia is bumping up its age-based vaccination plan by offering Oxford-AstraZeneca shots to Lower Mainland residents between the ages of 55 and 65.

The move comes a day after provincial health officer Dr. Bonnie Henry announced a pause on use of the same vaccine for anyone under 55 on the advice of the National Advisory Committee on Immunization over concerns about rare blood clots.

Henry says in a news release that officials know from the millions of doses used worldwide that the vaccine is highly effective and the benefits to those over age 55 far outweigh the very real risks of getting COVID-19.

“I encourage everyone in the Lower Mainland who is between 55 and 65 years of age to receive their safe and effective COVID-19 vaccine today,” Henry says.

Beginning Wednesday, those between the ages of 55 and 65 can call their local pharmacy and book an appointment to receive their vaccine.

Drop-in service may also be an option at more than 150 participating pharmacies and people must bring their personal health number with them.

The news comes as COVID-19 infections surge in the province, prompting additional restrictions on indoor dining, fitness and faith services announced on Monday.

There were 840 new daily cases on Tuesday but no deaths. More than 99,000 people have been diagnosed with COVID-19 in B.C. since the pandemic began and 1,455 have died.

There have been 320 new confirmed cases that are variants of concern in B.C. for a total of 2,553 cases.

The bulk of variant cases involve the B.1.1.7 variant first identified in the United Kingdom, while another 49 cases are the B.1.351 variant first identified in South Africa and 370 cases are the P.1 variant first found in Brazil.

“We're moving ahead with our immunization plan and delivering on our promise to British Columbians to move as quickly as possible, and as safely as possible, to get them the vaccines that they have been waiting patiently for,” Health Minister Adrian Dix says in the release.

On Monday, Henry said British Columbia has a “very robust” vaccine safety program and also monitors research outside the province.

She said instances of blood clots are “very rare” but British Columbia, along with other provinces, put a pause on the use of AstraZeneca on people under 55 for a few days until it receives further information from Health Canada.

“What we do know is this is very rare and it's unlikely we will see any cases here in British Columbia or Canada,” Henry said.

It's also a condition that can be tested for and treated, she said.

Henry said programs and advice would be updated in the coming days.

The National Advisory Committee on Immunization's recommendation on Monday marked the third time the committee had changed its guidance about the use of AstraZeneca.

In late February, the committee said it shouldn't be used on people over the age of 65, citing an insufficient number of seniors involved in clinical trials. Two weeks later, it retracted that advice, based on real-world evidence of AstraZeneca's effectiveness in seniors.

Fiona Brinkman, a professor of molecular biology and biochemistry at Simon Fraser University, said she could not comment directly on the AstraZeneca vaccine without seeing the data but said it appears public health officials are erring on the side of caution.

More concerning to her is misplaced fear about vaccines in general, she said.

Brinkman said a high proportion of the population needs to be vaccinated in order to stop the disease, particularly contagious variants like B.1.1.7 that are spreading rapidly.

“My biggest concern is that people are going to start getting hesitant about getting the vaccine because it's absolutely essential to get a vaccine,” said Brinkman, who also works with the Canadian COVID-19 Genomics Network.

The AstraZeneca vaccine is being offered to 55-to-65-year-olds through a partnership between Immunize BC and community pharmacists.