Do you need a spring COVID-19 vaccine? Research backs extra round for high-risk groups

New guidelines suggest certain high-risk groups could benefit from having another dose of a COVID-19 vaccine this spring — and more frequent shots in general — while the broader population could be entering once-a-year territory, much like an annual flu shot.

Medical experts told CBC News that falling behind on the latest shots can come with health risks, particularly for individuals who are older or immunocompromised.

"Even when the risk of infection starts to increase, the vaccines still do a really good job at decreasing risk of severe disease," said McMaster University researcher and immunologist Matthew Miller.

Back in January, Canada's national vaccine advisory body set the stage for another round of spring vaccinations. In a statement, the National Advisory Committee on Immunization (NACI) stated that starting in spring 2024, individuals at an increased risk of severe COVID may get an extra dose of the latest XBB.1.5-based vaccines, which better protect against circulating virus variants.

That means:

The various spring recommendations don't focus on pregnancy, despite research showing clear links between a COVID infection while pregnant, and increased health risks. However, federal guidance does note that getting vaccinated during pregnancy can protect against serious outcomes.

"Vaccinated people can also pass antibodies to their baby through the placenta and through breastmilk," that guidance states.

Multiple provinces have started rolling out their own regional guidance based on those early recommendations — with a focus on allowing similar high-risk groups to get another round of vaccinations.

B.C. is set to announce guidance on spring COVID vaccines in early April, officials told CBC News, and those recommendations are expected to align with NACI's guidance. 

In Manitoba, high-risk individuals are already eligible for another dose, provided it's been at least three months since their latest COVID vaccine.

Meanwhile Ontario's latest guidance, released on March 21, stresses that high-risk individuals may get an extra dose during a vaccine campaign set to run between April and June. Eligibility will involve waiting six months after someone's last dose or COVID infection.

Having a spring dose "is particularly important for individuals at increased risk of severe illness from COVID-19 who did not receive a dose during the Fall 2023 program," the guidance notes. 

And in Nova Scotia, the spring campaign will run from March 25 to May 31, also allowing high-risk individuals to get another dose.

Specific eligibility criteria vary slightly from province-to-province, so Canadians should check with their primary care provider, pharmacist or local public health team for exact guidelines in each area.