Canada will allow vaccine mixing for second doses
By Ian Austen for the New York Times |
Facing vaccine shortages, Canada’s immunization advisory body is recommending that some Canadians follow up their AstraZeneca shots with a different vaccine on the second dose.
The National Advisory Committee on Immunization said on Tuesday that people who had received a first dose of the AstraZeneca vaccine could be given either the Pfizer-BioNTech or Moderna vaccines as their second dose. It also said that the Pfizer and Moderna vaccines could be used interchangeably, although it recommended sticking with a single brand when possible.
While Canada’s health care system has generally been efficient in dispensing shots, no vaccines are manufactured in the country and larger shipments did not begin arriving until the past several weeks. To ensure that the maximum number of Canadians have some protection, Canada focused on getting at least one dose to as many people as possible. While 62 percent of Canadian adults have been given at least one shot, only 5.7 percent are fully vaccinated.
The advisory panel’s recommendation came as many provinces are starting to ramp up second doses, and it may resolve a potential headache.
Most of the increased shipments of vaccine have come from Pfizer, while supplies of the Moderna and AstraZeneca vaccines have been in much shorter supply. To date, 19.3 million doses of Pfizer’s vaccine have come to Canada, compared with 5.7 million doses of Moderna and 2.8 million Astra Zeneca shots.
The ability to substitute Pfizer’s vaccine for second doses eliminates concerns about limited supplies.
The advisory panel said that its recommendation followed similar advice from Denmark, Finland, France, Germany, Norway, Spain and Sweden. Several studies have shown that mixing vaccines is safe and effective, the committee said.
Seven of Canada’s 10 provinces, whose health care systems perform the vaccinations, have said they will allow people to change course between doses.