Here's how B.C. is rolling out fall boosters of COVID-19 vaccine

The B.C. government expects to begin sending invitations for fall COVID-19 vaccine boosters by the end of the week, pending the arrival of the first shipment of Omicron-targeting bivalent doses.

Health officials unveiled their plans for the province's latest vaccine rollout Tuesday afternoon, while stressing the ongoing importance of maintaining strong immunity against the various iterations of the virus.

"It is without a doubt vaccination that has allowed us to get to this point where we no longer need to have broad imposed measures – like mask mandates, like closures, like distancing – that we know are so disruptive to society," provincial health officer Dr. Bonnie Henry said, appearing in her first COVID-19 news conference in months.

"Because so many people have stepped up and received their immunizations, we are in a very different climate now than we were even just a year ago."

Henry noted that immunity is complicated, with individuals benefiting from different levels of protection that last different lengths of time depending on their circumstances, but pointed to studies that have found there is much better protection among those who are boosted.

PRIORITIZING FALL BOOSTERS

Officials confirmed the earliest appointments for bivalent shots will be given to residents who are at higher risk of severe infection, such as the immunocompromised, and to those who have waited the longest since their last dose.

Recipients will generally have to wait at least six months since their previous shot, though there will be exceptions for some vulnerable groups, including residents of long-term care homes, who could receive their fall booster just three months after their last dose.

Anyone who has caught COVID-19 recently should wait three months before getting their fall booster, officials said.

Around 109,000 doses of Moderna's newly authorized bivalent vaccine are scheduled to arrive in B.C. this week, with expected shipments increasing to 405,000 by mid-month. The government noted it's also possible that hundreds of thousands of weekly doses of Pfizer-BioNTech's bivalent vaccine will be arriving in the province by that time, pending Health Canada approval.

B.C. is making bivalent doses available to all adults, and to those between the ages of 12 and 17 who are at increased risk from COVID-19.

Children between the ages of five and 17 who have no risk factors will be given a regular vaccine dose for their fall booster, and there is no booster eligibility for anyone under five. 

Officials anticipate reaching peak capacity for vaccine distribution by the end of September, at which point around 280,000 people should be receiving a dose every week.

Pharmacies will be the first to offer the vaccines, with more than 500 locations across the province participating in the early distribution. Health authorities will follow with dedicated vaccination clinics that will begin opening on Sept. 19.

Officials encouraged the public to ensure they are registered through the province's Get Vaccinated website so they can receive their invitation and secure their appointment. More than four million invitations are expected to be sent over the coming weeks.

WHAT IS A BIVALENT VACCINE?

Multivalent vaccines are nothing new, with annual influenza shots notably carrying three or more virus strains in an effort to target the ones most likely to cause illness in a particular flu season.

Moderna's bivalent vaccine, which was authorized for use in Canada last week, targets the original COVID-19 strain along with the BA.1 Omicron subvariant.

The dose is slightly different from the one approved by the U.S. Food and Drug Administration, which targets the BA.4 and BA.5 Omicron subvariants, which are believed to account for the majority of new cases in Canada.

Henry stressed that clinical trials found the BA.1 vaccine offers "a very strong immune boost against all of the Omicron strains," including BA.4 and BA.5.

The government said people will be able to receive their fall COVID-19 vaccine booster and flu shot at the same appointment beginning sometime in October, at both pharmacy and health authority clinic locations.

Health officials are hopeful uptake will be high for both vaccines this year, to help ward off an expected surge in illness heading into November and December.

Some 1.3 million B.C. residents never responded to their invitation to get a first COVID-19 booster, though a government survey indicated 35 per cent of those – or about 455,000 people – intend to get one this fall.

Approximately two-thirds of people who did receive a first booster said they will "definitely" get another, according to the province, and 21 per cent said they likely will as well.

Henry noted the trajectory of the pandemic remains "very uncertain," and said with significant transmission continuing around the world, there remains an ongoing risk that another variant of concern will emerge.

"We do know more and more about the virus and about how we can manage, both individually and collectively in this province – but we are not yet at a point where we can let our guard down," she said.

"We need to keep it up to be certain we are protecting those most at risk, and protecting our health-care system in the coming months."