VANCOUVER -- After extending the recommended timeline between first and second doses of COVID-19 vaccines to cover as many people as possible earlier on in the pandemic, B.C. health officials have now shortened the gap again.

Provincial health officer Dr. Bonnie Henry and Health Minister Adrian Dix announced Thursday that B.C. is now recommending an eight-week gap between shots, down from the 16 weeks previously announced.

Invitations to book second-dose appointments have already begun being sent out to people who are clinically extremely vulnerable and those who received their first doses near the start of the province's rollout, including the elderly, health-care workers, long-term care residents and those in remote communities.

"About 400,000 people over the age of 70 and clinically extremely vulnerable will start receiving their invites today," Henry said.

She said the accelerated timeline for second doses should mean everyone in B.C. will be able to be fully vaccinated by the end of the summer.


The provincial health officer announced the expedited timeline on the same day that B.C. surpassed three million total doses of vaccines administered.

Nearly 66 per cent of British Columbians ages 18 and older have now received first doses, Henry said. Among all those ages 12 and older who are currently eligible, roughly 62 per cent have received a first dose, she added.

Almost all of the 3,032,811 doses B.C. had administered as of Thursday were first doses. Just 156,730 were second doses.

That disparity is by design. Until now, B.C. has been focused on increasing the level of immunity in communities by ensuring that everyone has an opportunity to get their first dose, Henry said.

"We are making great strides and we want to keep this momentum going," she said. "We now have sufficient, confirmed deliveries of vaccine in our age-based program - that's the Pfizer and Moderna vaccines - that we can move up the interval."

Henry said efforts to provide second doses in long-term care homes have already been underway for some time, and the province expects to have offered second doses at all such facilities "in the next few days to weeks."

She also highlighted the plan for second doses in remote and Indigenous communities where B.C. gave first doses using a "whole of community approach." In those regions, everyone 18 and older was offered a first dose at the same time, and second doses will be offered the same way, Henry said.

"There's no need, if you're in one of these communities, for communities to reach out," she said. "We will be coming to you, and we're co-ordinating that with the First Nations Health Authority and the regional health authorities."


The provincial health officer also took time to acknowledge concerns people who received the Moderna vaccine for a first dose might have, given that the province has sometimes experienced delays in receiving shipments of the vaccine.

"It's much easier, logistically … for Moderna to be taken to some of the more rural and remote communities," Henry said. "We are prioritizing the supplies of Moderna that we have right now to be able to make sure that when we do communities that have received Moderna for their first dose, they can receive it for their second dose."

Still, there is a possibility that some people in B.C. who received Moderna for their first dose will be offered Pfizer as a second dose, Henry said.

She cited research from Canada's National Advisory Committee on Immunization concluding that, while it's preferable to receive the same vaccine for both doses, messenger RNA vaccines like Pfizer and Moderna can be used interchangeably if necessary.

"It is safe and it does work," Henry said. "If you had a Moderna vaccine first, you can receive a Pfizer vaccine for your second dose."

The province will ensure that as many people as possible receive the same vaccine for both doses, but there may be some people who received Moderna in large, urban vaccine clinics who will be offered Pfizer for their second dose, Henry said.

"I would encourage people to take the Pfizer if it is on offer," she said. "We know that it is safe and works just as well if you have one or the other of the mRNA vaccines."


For those who received the AstraZeneca vaccine for their first dose, either at a pharmacy or through a workplace that was prioritized for immunization, Henry's message was to "hold tight for a few more days."

"Our focus this week is on the age-based program and I anticipate we'll have more information by the end of next week to be able to provide advice to people who've received AstraZeneca, so they can make an informed decision about receiving AstraZeneca as (their) second dose or receiving one of the mRNA vaccines," the provincial health officer said.

She said the province is still awaiting more information from studies on the AstraZeneca product being conducted in the U.K. and elsewhere.

Health officials are also working out the logistics of getting second doses of AstraZeneca to the locations where first doses were administered, including pharmacies, Henry said.

"I want to assure people that we will have enough of the AstraZeneca vaccine to provide second doses for everybody who wants that," she added.

Henry noted that B.C.'s stock of AstraZeneca, which is being held for second doses, does not expire until the end of June. She said some people in Ontario had been offered second doses of AstraZeneca because of expiring supply, but said she does not anticipate that being an issue here.


B.C.'s Get Vaccinated website continues to be the main way the province is communicating with residents and scheduling vaccine appointments.

For the thousands of people who received a first dose before the website launched on April 15, Henry encouraged registering to receive an invitation to book a second-dose appointment.

The province has vaccination records for all individuals who were vaccinated before the registration system went live, but it doesn't have email addresses or phone numbers to contact them easily, Henry said.

She said those who received a first dose before April 15 and haven't registered can expect a letter in the mail inviting them to book a second-dose appointment, but noted that the process would likely be slower than it would be if they registered online.

"If you've not already done so, please get registered and get vaccinated today," Henry said. "It's simple, it's fast, and getting vaccinated is important and integral to restarting our province and our lives."