A mucosal vaccine could be a COVID-19 game-changer. So why doesn’t Canada have one?

With the arrival of XBB.1.5 in Canada, some scientists say governments must invest more in mucosal vaccines — a tool that could be a game-changer in the fight against COVID-19.

With the arrival of the highly contagious XBB.1.5 Omicron subvariant in Canada, some scientists say governments must invest more in developing mucosal vaccines — a tool that could be a game-changer in the fight against COVID-19.

Mucosal vaccines, which are inhaled in the nose or mouth, are widely considered by doctors and scientists to be the next generation in protecting against COVID-19 because they offer the greatest potential to prevent transmission of the virus — a feature that injected mRNA and adenovirus vaccines do not offer.

But while some countries, including China and India, have moved forward and authorized new inhaled vaccines, Canada is among the many nations that still do not yet have a mucosal vaccine against COVID-19 approved.

That’s something that needs to change soon if the country truly wants to return to some semblance of pre-pandemic ‘normal,’ says Dawn Bowdish, an immunology professor at McMaster University.

“Many of our policymakers and politicians have really thought that as soon as we get everyone vaccinated, we can just go back to normal,” she said.

“But until we get vaccines that actually stop transmission, we actually need to have a compromise between non-pharmaceutical interventions like masking and vaccination.… If we truly want to go back to a pre-COVID life, we are going to need to invest in mucosal vaccines.”

COVID-19 vaccines currently in use in Canada, such as those produced by Pfizer and Moderna, are injected into the arm’s muscle tissue and work by stimulating an immune response mainly in an individual’s blood.

This has proven to provide protection against severe infection that could cause hospitalization or death, but it does not always prevent transmission of the virus, Bowdish said.