VANCOUVER -- With Canada approving a third COVID-19 vaccine, B.C.'s health officials say those doses will likely go to essential workers first.

Canada approved the AstraZeneca COVID-19 vaccine on Friday, and since there is less data on its efficacy for those over the age of 65, B.C.'s top doctor said Monday another group will be prioritized.

"Once we know how much we'll be receiving here and when, we will be able to further expand who is receiving vaccine," Henry said.

"We do believe that we will start to target essential workers, particularly our first responders and our key essential workers who are not able to work from home."

Henry said officials hope to reduce workplace spread.

"We've had a number of places in communities around the province where we've had outbreaks, if we think about things like poultry workers working, people who work in some of our mail distribution centres," she said.

"So our B.C. immunization committee will be looking at how do we best use the doses that we have coming in."

Henry said first responders like police, firefighters and 911 dispatch officers are being considered.

"That is one group. But we have a whole group of people that we have come to appreciate are a part of what keep our economy, but (also) our society functioning during this pandemic," she said.

"That is everybody from educators, poultry workers, grocery store workers and we are working on which of those are most at risk from infections and outbreaks."

Paramedics, Henry explained, are included in the rollout alongside other health-care workers because of their roles in hospitals and care homes.

Unlike the Pfizer-BioNTech and Moderna vaccines, the AstraZeneca vaccine doesn't require below-freezing storage and instead is stable at fridge temperatures.

Henry says that will allow health authorities "to be more agile," and use current the vaccine distribution infrastructure that's already in place in the community.

Henry explained essential workers eligible for the AstraZeneca vaccine will be able to choose if they want to receive that dose earlier or wait for the age cohort to receive a Moderna or Pfizer vaccine.

"There will be a limited amount of choice," she said.

"We obviously encourage people to get the vaccine that's available to them as soon as possible and we know how exciting it is to have three very safe and very effective vaccines."

The top doctor said officials don't expect shipments to be quite as large as the Pfizer and Moderna vaccines, however.

The first shipment of the AstraZeneca vaccine is expected to arrive in B.C. next week and have about 60,000 doses.

"This is exciting news," Henry said. "This means we'll be able to move everybody up in the queue."