B.C.’s Dr. Bonnie Henry defends extending interval between COVID-19 vaccine doses

VANCOUVER (NEWS 1130) – Provincial Health Officer Dr. Bonnie Henry appears to be close to getting some backing for her recent decision to lengthen the time between first and second COVID-19 vaccine doses in B.C.

A national expert panel is reportedly ready to align with B.C.’s move to extend the interval to four months, quite an increase from the previous 42-day recommendation.

Henry has said the strategy is based on data and she defended on Tuesday the planned delay between doses, referencing a number of studies backing the move including data from the U.K., Israel, and here in B.C.

“We are in a position where we are looking at the data from the UK but we are also in a position that’s quite different from the U.S. in terms of our vaccine availability in the short-term,” she explained. “And we are at a position where we still have ongoing transmission in our communities in quite a serious way.”

Watch: BCCDC’s Dr. Danuta Skowronski provides data supporting B.C.’s decision to delay second doses

B.C.’s top doctor also noted the benefits of delaying second doses isn’t limited to how many more people will receive the shot sooner. She explained that the “timing of the booster dose can sometimes confer additional benefit in terms of the strength of the immune response, particularly the cell-mediated immunity and have a prolonged benefit in how long the response lasts.”

She stressed that context is important, noting the decision to extend the timeframe between doses is something that works for B.C. in its current situation.

“This makes sense for us knowing that it is a critical time right now with the limited amount of vaccines that we have in the coming weeks to be able to provide that protection that is safe and long-lasting in the short-term — so for several months — to everybody here,” she said, also addressing critics of the strategy, including Canada’s top science advisor.

Related articles: 

• B.C. extends wait between COVID-19 vaccine doses to four months

• Ontario waits for national guidance as B.C. pushes ahead with delayed second dose

• Experts caution against comparing COVID-19 vaccines

“It is a little bit unfortunate that the national science advisor who obviously was not involved in some of these discussions and decision making, and perhaps didn’t understand the context that this decision was made in,” Henry noted, adding health officials will continue to monitor vaccine administration and efficacy.

Canada’s National Advisory Committee on Immunization is expected to issue a statement Wednesday on the interval between doses of COVID-19 vaccines. The Globe and Mail cites sources who say it will align with B.C.’s decision, and that guidance would open the door to more first shots to be given more quickly across the country.

Alberta is considering whether to follow suit while Ontario has said it is waiting for a recommendation from NACI before delaying second doses.

Editor’s note: This article has been updated to correct the initial recommended timeline between first and second doses.