How Bivalent mRNA Vaccine Boosters Work
Here I give a summary of how the bivalent mRNA vaccine boosters for Covid-19 work. The mechanism of immune response action is the same as the mRNA vaccine series made by Pfizer / BioNTech or Moderna. But, this time we get two sets of instructions in one shot.
The first set of instructions encodes for our bodies to make the spike protein on SARS-CoV-2 (ancestral strain). The second set of instructions encodes for our bodies to make a mutated form of the spike protein, such as the Omicron variant spike protein.
I want to emphasize that targeting multiple serotypes (strains) of a pathogen is not new. This technique is used in many vaccines like the HPV vaccine that targets 9 strains or the pneumococcal vaccine that targets 23 strains.