Could New Brunswickers receive a 'vaccine cocktail'?

·4 min read

When Quebecers get their second COVID vaccination, or booster, the vaccine could be from a different manufacturer than their first shot.

And New Brunswickers are waiting to find out if that could happen here.

Quebec has been trying to give people the same type of vaccine for both shots, based on accepted protocols, said Dr. Horacio Arruda, Quebec's director of public health, at a news conference last week. But if the same vaccine type is unavailable or the protocols on who gets a particular vaccine have changed, Arruda said he believes that recommendation may also change.

And it is possible immunity could be even better with a combination of vaccines, Arruda said, although it is a view experts are split on.

Some experts say while more research is needed, even if there isn't more of a benefit, it increasingly looks like there probably wouldn't be a risk, said Dr. Susan Kirkland, head of the department ofc community health and epidemiology at Dalhousie University. She said the potential that two vaccines used on one individual could target different elements of the virus is also possible.

Colloquially, receiving two different vaccine types is referred to as a "vaccine cocktail."

In New Brunswick, hundreds of high school teachers and staff, rotational workers and others received a dose of the AstraZeneca vaccine prior to protocols changing to direct it not to be used for younger people due to rare incidents of blood clots that occurred mostly in young women.

Rick Cuming, president of the New Brunswick Teachers’ Association, said while they don't have exact numbers of how many high school teachers received a first dose of AstraZeneca, upward of 90 per cent of members were vaccinated at high school clinics completed over an approximate one-week period.

“Teachers are awaiting information on what the next step will be. We don’t know what type they will receive for their next dose,” he said.

Teachers are reaching out to the association, Cuming said, but there is little he can tell them besides to wait and see. Public health has indicated the teachers who received one shot will receive a second within the 16-week period, he said.

The province receives all of our guidance from the National Advisory Committee on Immunization, said Dr. Jennifer Russell, New Brunswick’s chief medical officer, and she said NACI’s advice thus far has been to match the vaccine given for the first dose.

"The guidance on the use of AstraZeneca has been evolving since it was approved earlier this year," she said.

Discussions are ongoing, she said, as to whether younger people who received the AstraZeneca vaccine in their first dose should receive the Moderna or Pfizer as their second dose. Research is emerging from the U.K. on this, Russell said, and Canada is looking at that as it makes decisions.

On Thursday at a COVID-19 briefing Russell directly addressed New Brunswickers who had received a dose of the AstraZeneca vaccine. "Many may be wondering about what happens when it is their turn for a second dose," she said.

She said New Brunswick does not expect to receive another shipment of this vaccine type until late May.

As NASI has now revised its position, stating AstaZeneca could be used for those as young as 30, New Brunswick will be reviewing information by NASI to determine whether those who received AstraZeneca for their first dose should receive it for their second dose, but results of the U.K. study will be key, she said.

"There are harms and benefits to every single drug," said Kirkland, but that rules are changing based on the best emerging evidence is actually a good thing. This process always occurs, in this case, "we're just doing it under a public microscope," she said.

A bigger concern, Cuming said, is that elementary, middle and supply teachers have received no vaccines to date, despite being in classrooms where social distancing is not possible, and often teaching in multiple classrooms depending on areas of specialization.

The association wants these teachers prioritized for a first dose of a vaccine before tackling the issue of second doses for high school teachers, he said.

Russell said working to ensure all New Brunswickers receive a first dose in paramount.

Clara Pasieka, Local Journalism Initiative Reporter, Telegraph-Journal