VANCOUVER -- Tens of thousands of B.C.’s frontline and essential workers were supposed to receive the AstraZeneca vaccine in an immunization campaign that would run alongside the current age-based program.

Concerns around blood clots, prompted by rare incidents in other parts of the world, has changed that. Right now, AstraZeneca can only be administered to people between the ages of 55 and 65 at pharmacies.

That has some infectious disease experts suggesting essential workers be given the Pfizer and Moderna vaccines, even if that means diverting and delaying doses for those in the age-based program.

“The most effective way to use those vaccines is to vaccinate those who are at high risk of infecting others, who are at high risk of being exposed,” said Caroline Colijn, an infectious disease modeller at Simon Fraser University.

Dr. Brian Conway at the Vancouver Infectious Disease Centre agrees.

“We have to have a very dynamic vaccination plan that would now favour I would say younger adults, who are fueling transmission," Conway said.

They acknowledge there may be some push back from British Columbians in their 50s and 60s who are next in line to be vaccinated. They think an education campaign on the benefits of vaccinating younger frontline workers would help.

“I want to just shout out to those 50 and 60 year olds: What is better than having a vaccine in six weeks? You know what’s way better than that? It’s having a vaccine in eight weeks, but having only a quarter of the risk of exposure for those eight weeks. That is actually better for you,” said Colijn.

Provincial health officer Dr. Bonnie Henry says the province has already been vaccinating employees at some high-risk workplaces with Pfizer and Moderna.

“Quite frankly, they often are the larger workplaces where people are more poorly paid, and we know that it involves many of our racialized communities, people who live in large, multi-generational homes. So that has been our focus to start with,” said Henry.

She won’t commit to making Pfizer and Moderna available to all frontline and essential workers, instead hoping Johnson & Johnson doses arrive later this month to jump start that campaign. Conway says it’s a mistake to wait.

“I hope that there are people advising her on this being a very credible option,” he said.

Colijn predicts if B.C. continues to focus on age-based vaccination, COVID-19 case numbers will keep rising.

“I think we are in for really rough ride in the next few months anyway, but much much rougher if we cant stop transmission,” she said.