To make an effective vaccine more quickly against never-before-seen, fast-spreading viruses such as SARS-CoV-2, researchers at Vanderbilt and elsewhere are using alternate approaches. In one approach, instead of proteins, a new generation of vaccines, called mRNA vaccines, will carry the molecular instructions to make the protein.

Instead of the standard vaccines where viral proteins are used to immunize, an mRNA vaccine provides a synthetic mRNA of the virus, which the host body then uses to produce the viral proteins itself.

The biggest advantage of the mRNA vaccines is that they can bypass the hassle of producing pure viral proteins, sometimes saving months or years to standardize and ramp up the mass production.

The mRNA vaccines basically mimic the natural infection of the virus, but they contain only a short synthetic version of the viral mRNA which encodes only the antigen protein. Since the mRNA used in vaccination cannot become part of the person’s chromosomes, they are safe to use. Such mRNA vaccines would also be safer than the weakened viral or protein-based vaccines because they do not carry the risk of the injected virus becoming active, or a protein contamination.