This is it: Health Canada has just approved the first bivalent vaccine adapted to the Omicron variant, from Moderna, as a booster dose for people aged 18 and over. Here is what we know about this vaccine.
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Effective against BA.4 and BA.5
“Clinical trial results have shown that a booster dose of Moderna’s Spikevax bivalent vaccine elicits a strong immune response against the Omicron strain (BA.1) and the original SARS-CoV-2 virus strain. It has also been observed to generate a good immune response against the Omicron BA.4 and BA.5 subvariants, and is expected to prolong the durability of protection,” says Health Canada.
Canada has already ordered 12 million doses of this vaccine.
A “bivalent” vaccine
The main advantage of this new vaccine is that it is “bivalent”, therefore capable of attacking both the original strain of the virus and the Omicron variant. It’s still a messenger RNA vaccine, the technology behind vaccines from Moderna and Pfizer-BioNTech.
“This is good news, because by combating current and past strains, it makes it possible to prevent one of these strains or one of these variants from becoming a problem again”, supports Alain Lamarre, specialist professor in immunology and virology at the National Institute for Scientific Research (INRS).
What side effects?
Much like Moderna’s Spikevax booster shot, the side effects “are also mild and wear off quickly.”
A miracle vaccine?
However, we should not expect this new vaccine to work miracles: the virus is still circulating a lot in the world, which increases the risk of seeing a new variant appear capable of thwarting it, underlines Alain Lamarre.
Recall that the British drug regulator announced last week that it had approved Moderna’s next-generation COVID-19 vaccine, which targets the Omicron variant.
Current vaccines: still effective?
If you have already been to get your booster dose, don’t panic: the other vaccines are still effective in preventing complications, says Alain Lamarre.
“Current vaccines are based on the original Wuhan strain and are less effective than before in preventing contracting the virus, especially due to the Omicron variant. However, protection against severe disease, and therefore against hospitalizations and death, remains good. We are talking about more than 65% for someone who was vaccinated more than 5 months ago. However, at the dawn of an autumn wave, we want to increase this protection again towards 85%. That’s what the booster dose is for, ”explains the virologist.
And what about Pfizer?
Pfizer also submitted a submission for its bivalent vaccine version in late July, and is awaiting approval from Health Canada.