Two-strain booster vaccine

Moderna’s bivalent coronavirus vaccine contains two components which attack both the original strain of the virus and the Omicron variant with antibodies and immune response cells


SARS-CoV-2 virus

Spike protein: Binds to ACE2* receptor to enable virus to enter cells and initiate infection

Omicron: Variants harbour mutations in spike protein which increase infectivity

Synthetic mRNA†: Includes code to produce virus spike protein for original virus and Omicron variant

Human cell

Viral genome: Contains instructions for making protein

ACE2 receptor

mRNA†: Packed in lipid nanoparticles
Microscopic oily droplets stop body’s enzymes from breaking mRNA down

Human cell

Synthetic RNA

Antibodies 

Protein

T cells

Response in human cell: mRNA temporarily produces spike proteins of both original virus and Omicron variant. Body will then recognise these proteins as foreign, produce antibodies and activate T cells to attack


*angiotensin-converting enzyme 2 

†messenger ribonucleic acid


Sources: Bloomberg, European Medicines Agency, Financial Times, Nature 
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