Adjuvants are for activating the immune system to respond to free-floating virus particles. If the virus actually infects a cell and produces proteins on the cell’s surface, that is a different signal to the immune system and adjuvants are not needed. Thus adjuvants were not needed for traditional live/attenuated vaccines and 21st century mRNA and vector vaccines (AZ, etc), but were needed for 1980s recombinant protein vaccines (Novavax) and traditional dead/inactivated vaccines.
Adjuvants are for activating the immune system to respond to free-floating virus particles. If the virus actually infects a cell and produces proteins on the cell’s surface, that is a different signal to the immune system and adjuvants are not needed. Thus adjuvants were not needed for traditional live/attenuated vaccines and 21st century mRNA and vector vaccines (AZ, etc), but were needed for 1980s recombinant protein vaccines (Novavax) and traditional dead/inactivated vaccines.