Coronavirus vaccine vials may hold more doses than previously thought, officials say

Vials of the coronavirus vaccine delivered to Canada earlier this week could be holding more doses than previously thought.

Alberta’s Chief Medical Officer Dr. Deena Hinshaw told reporters Thursday that it was possible some vials may have enough to provide six doses of the Pfizer-BioNTech COVID-19 vaccine — one more than the five doses that were initially thought to be in each vial.

“When creating these vials, there is enough put in the vials to make sure there’s a guaranteed five doses in each vial,” said Hinshaw in response to questions about the extra dosage.

“If you have a very skilled immunization administrator who’s able to withdraw exactly the amount needed and no more, it is possible that some vials may be able to provide enough for six doses of vaccine. That is something that our immunizers are looking at … we’d be able to provide that extra dose whenever that vial is handled in a way to make that last dose available.”

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Hinshaw said that the extra doses would hopefully increase the number of people they could immunize with the province’s current share of Canada’s initial shipment of 30,000 doses.

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Major-General Dany Fortin previously told CBC’s Power and Politics on Thursday that both the Public Health Agency of Canada and Pfizer-BioNTech told provinces they could extract six doses from each vial of the vaccine.

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Health Canada did not give an immediate response to Global News’ request for comment on reports of the extra doses, as well as how many vaccine doses were now confirmed to be in each province.

In a statement to the Canadian Press however, the health agency said that it was aware of vials potentially containing more than the five doses of the 0.3 millilitres shown on the vial’s label.

“Health Canada has no objections to health-care professionals drawing up an additional dose or two from each vial, where possible,” the agency told CP, also noting that the extra doses were a result of safeguards against potential loss of vaccine that could happen anytime during its handling and storage.

“However, it is important to note that the mixing or pooling of volumes from separate vials is not recommended as it could result in cross contamination, loss of product sterility or improper dosing.”

In a statement to Global News, Pfizer said that the vaccine remaining in the vials after administering five doses can vary “depending on the type of needles and syringes used plus the amount of diluent added.”

“If the amount of vaccine remaining in the vial cannot provide a full additional dose, the vial and any excess volume must be discarded,” read the statement, which also warned that excess vaccine from multiple vials “must never be pooled.”