What are viral vector-based vaccines and how could they be used against COVID-19?
How do such vaccines trigger immunity?
Various viruses have been developed as vectors, including adenovirus (a cause of the common cold), measles virus and vaccinia virus. These vectors are stripped of any disease-causing genes and sometimes also genes that can enable them to replicate, meaning they are now harmless. The genetic instructions for making the antigen from the target pathogen are stitched into the virus vector’s genome.