The speed of the development of the coronavirus vaccines and their effectiveness in keeping people alive and out of the hospital is nothing short of remarkable. The vaccines even showed significant levels of protection against several variants of Covid-19. Then came omicron. This highly transmissible variant has torn through countries, even those with a substantial portion of their population vaccinated. Vaccinated individuals who got sick had lots of virus in their noses, which means they can still infect others.
As a result, many scientists are looking to other strategies to find the best way to fight future variants, with the goal being a higher level of protection. The ultimate success would be to block infections completely. One area being explored with great interest is the delivery of a vaccine via nasal spray.
The switch in the vaccine delivery route could cause a wall of immunity right where the viruses enter the body and block their spread, maybe even preventing mild infections. Placing the vaccine in a person’s nostrils could provoke “mucosal” immunity, meaning the immune system has virus-fighting components in the tissue that lines the person’s airways. This localized protection could halt transmission.
It’s vital to note that this strategy is still early in development. So, don’t expect it to be available any time this year. Further, some scientists question whether the goal of blocking transmission and mild infections is too ambitious. Typically, the primary purpose of vaccination is to prevent severe sickness.
However, a growing number of scientists think a vaccine that stops transmission is precisely what is needed rather than having to keep doing what we’ve been doing…playing catch-up. For the past year, scientists have been in this constant cycle of testing current and revised vaccines against the growing number of new variants. While boosters are shown to be effective, the protection is short-lived.
The omicron variant caused a surge in cases this past winter that proved the virus’s ability to keep evolving, resulting in the protection from existing vaccines waning and indicating a different solution is needed going forward. Several companies are now working on developing nasal vaccines, but it’s too early to know if they’re effective and when they’ll be available.