TORONTO (Reuters) - Quebec may space out doses of COVID-19 vaccines by as long as 90 days, the province said on Thursday, beyond the 42-day interval recommended by a national advisory council, as high case loads threaten to overwhelm its hospitals.
The approach is similar to that in the United Kingdom, where drug regulators have said shots can be administered up to 12 weeks apart.
"Our experts recommend that the second dose of the vaccine be given between 42 and 90 days. In our context this is the best strategy because we have to deal with very few vaccines," said Quebec Health Minister Christian Dubé.
Quebec imposed a night curfew last week to combat soaring cases. It reported 2,132 additional cases and 63 more deaths on Thursday.
Pfizer and BioNTech's COVID-19 vaccine was authorized in Canada with 21 days between doses, and Moderna's vaccine with a 28-day interval.
Canada's National Advisory Committee on Immunization (NACI) has said efforts should be made to vaccinate on that schedule but acknowledged on Tuesday some places may wish to protect more people by delaying the second dose, giving it "preferably within 42 days" of the first dose.
The European Medicines Agency has said there should be a maximum interval of 42 days between the first and second shots of the Pfizer vaccine.
"The efficacy of the vaccine should be the same up to 42 days. After 42 days, we really don't know," Canada's deputy chief medical officer, Howard Njoo, said during a separate briefing. "There's no new data there."
Njoo echoed a statement from Canada's Council of Chief Medical Officers of Health, which said any vaccination program that extends doses beyond 42 days should monitor the impact of that policy and share results regularly.
Njoo noted that non-COVID-19 vaccines tend to be as effective, or more effective, when given further apart.
(Reporting by Allison Martell; Editing by Steve Orlofsky)