Federal health officials are urging Canadians to get booster doses of the COVID-19 vaccine in advance of a possible resurgence of the virus in the fall.
While case counts and other indicators are stable or declining in most parts of Canada, the virus remains in circulation and could begin spreading further during the fall respiratory virus season, Canada’s chief health officer, Dr. Theresa Tam, said Thursday.
In addition, cases of two highly contagious COVID-19 variants of the Omicron strain called BA.4 and BA.5, which have been fuelling new outbreaks in the United States and Europe, have been increasing in Canada, causing additional concern.
“As the SARS-CoV-2 virus continues to circulate worldwide and new variants emerge and spread, we must remain vigilant and prepare for resurgence in the weeks and months ahead,” Tam said during a briefing Thursday.
That’s why health officials are strongly encouraging all Canadians to get up-to-date with their vaccines as soon as possible, which no longer means just two doses.
Canadians are now only considered up-to-date with their COVID-19 vaccines if they received their last dose within the last nine months, federal Health Minister Jean Yves-Duclos said.
“The immunity conferred by your primary series of two doses of vaccines administered in 2021 has now waned,” Duclos said.
“While you might have gotten infected, (the) risk is high you could get reinfected with all the downfalls, including the risk of developing symptoms of long COVID. As health experts and physicians will tell you, it’s critical that you go and get the shot that’s waiting for you.”
Governments “don’t want to return to more restrictive public health measures” and vaccination is a key measure to prevent this from being necessary, Dulcos added.
On Wednesday, the National Advisory Committee on Immunization (NACI) released new guidance for the fall recommending all Canadians who are at increased risk of serious illness from COVID-19 should be offered a booster dose regardless of the number of booster doses they have previously received.
It also said this guidance could also be extended to all individuals between the ages of 12 and 64.
“Up-to-date vaccination remains the foundation of our protection, individually and collectively, to help reduce the spread that leads to resurgence and to significantly lower the risk of hospitalization and death due to COVID-19,” Tam said Thursday.
Earlier this month, Tam told reporters during a briefing that COVID-19 vaccine efficiency wanes significantly over time, from 50 to 80 per cent effectiveness down to 20 per cent or lower six months after the second dose.
To date, only 60 per cent of Canadians have received a booster dose of the vaccine.
Tam acknowledged that convincing the 40 per cent of those who have yet to get boosted can be challenging.
The key, she says, is trying to understand why they have chosen not to do so.
“We’ve got to… continue to do those more targeted community-led efforts that try to understand why people are not taking up the vaccine as much as possible,” she said.
“I think today Canadians are following the advice if we explain to them that, in fact, protection from the vaccine could wane over time, the virus is changing and it’s important ahead of a respiratory virus season.”
As new variants emerge, a number of countries are now fielding applications from some vaccine manufacturers for new formulations of the COVID-19 vaccine with more targeted protection against mutations of the virus.
Tam says so far, none of these companies have submitted their data on updated vaccines to Canadian health regulators. She said she hopes this information will be submitted to Health Canada as soon as possible.
In the meantime, Canadians should get boosters while health officials wait for the results of any potential new vaccines, she said.
“I do think that right now … looking at ways to broaden immune coverage and immune response would be a very important objective,” Tam said.
“Canada will of course evaluate those vaccines as they come on board.”
On Wednesday, the World Health Organization called for accelerated efforts and incentives to see a pan-coronavirus vaccine developed for use across the globe.