There are important differences between mRNA vaccines and the Novavax protein vaccine.
How they work
The mRNA vaccines and protein-based vaccines are different types of vaccine. However, they are all inactivated vaccines. The crucial difference is the way in which the pathogen information is delivered to the immune system. mRNA vaccines stimulate the body to produce harmless copies of the spike protein. In protein-based vaccines, on the other hand, parts of the virus protein are directly injected into the body.
For the virus variants to date, we know that mRNA vaccines and the Novavax protein vaccine provide good protection against severe COVID-19 illness requiring hospitalisation. But the protection from the vaccine wears off over time, particularly in people at especially high risk. We recommend the booster vaccination, preferably with a variant-adapted (bivalent) mRNA vaccine or the Novavax protein vaccine, if available. It doesn't matter which vaccine was used for previous vaccinations. In terms of mRNA vaccines (Pfizer/BioNTech or Moderna), both the previous (monovalent) mRNA vaccines and the variant-adapted (bivalent) vaccines are suitable for the vaccination this autumn. Current data show that the previously used (monovalent) mRNA vaccines still provide good protection against severe illness requiring hospitalisation caused by the new Omicron variants. The autumn vaccination provides only minimal and short-term protection against infections with mild illness as very little can be done to prevent transmission of the virus to others.
Important: those who are pregnant or breastfeeding should receive an mRNA vaccine and not the Novavax protein vaccine.