B.C.’s top doctor said it is likely that many British Columbians will get a second dose of COVID-19 vaccine sooner than expected, although the short-term priority remains to get everyone their first dose as soon as possible.
Back in March, provincial health officer Dr. Bonnie Henry said the province would extend the interval between doses of Moderna and Pfizer vaccines to 16 weeks.
During a press briefing on Monday, Henry said that the gap between doses will likely be shorter than that.
“It’s likely for all of the vaccines that we have, as supply has come in, we’ll be able to move up second doses for everybody,” Henry said Monday.
Henry said the interval between doses was extended to 16 weeks to get a first dose of vaccine to as many people as possible as quickly as possible.
“Doing that protects all of us because we were able to get to that community level of reducing transmission,” she said.
Now that vaccine supply has increased, Henry said, second doses can boost protection even further.
“Dose two really is about increasing our own personal protection,” she said, noting that a second dose of Pfizer vaccine can boost effectiveness in preventing infections to over 90 per cent.
“That means that we can make sure that those who are older, those who are clinically vulnerable for different reasons, are able to get their vaccine dose as soon as we have a supply for dose two. So it is likely for everybody that we’re going to be able to move up that dose two.”
In response to a question about second doses, Henry said a second dose will provide better short-term protection in the form of antibodies, as well as “more durable and longer-lasting protection.”
That booster dose protection will “see us through the next year,” she said.
“We don’t yet know how long the single-dose protection lasts, but we absolutely do know that getting a booster dose will give longer-lasting protection,” said Henry.
Henry noted that there is also research that indicates delaying the second dose can produce better immune response, noting that protection after one dose of the Oxford-AstraZeneca vaccine goes up over a period as long as 12 weeks.
B.C’s remaining stock of AstraZeneca vaccine in B.C. — about 20,000 doses — is good until the end of June, Henry added.
“For all of those who have received their first dose, you will have the option of receiving your second dose of AstraZeneca,” she said, adding that additional stock is coming to the province.
Information will be coming in the next few weeks to help British Columbians who received the AstraZeneca vaccine make “an informed choice” about which vaccine they want to receive for their second dose.
The province is awaiting the results of a U.K. survey studying the efficiency of using AstraZeneca as a first dose and Pfizer as a second dose.
Earlier this month, Henry said those who received a dose of AstraZeneca vaccine may be given a choice as to what vaccine they receive for their second.
Henry said while the timeline for second doses may be moving up, the province’s focus is on getting as many people as possible to receive their first dose.
On Monday, the province reported 1,360 new COVID-19 cases over a 72-hour period, along with 14 deaths.
— With files from The Canadian Press