FDA approves first mRNA vaccine for seasonal flu

The U.S. Food and Drug Administration (FDA) has approved a new seasonal flu vaccine that uses mRNA as its base.

Moderna, the vaccine's maker, announced Wednesday (Aug. 5) that a vaccine advisory committee to the FDA unanimously agreed that the shot is safe and effective for preventing illness from seasonal influenza. The shot, called mFlusiva or mRNA-1010, has been approved for people ages 50 and older.

Similar to mRNA vaccines against COVID-19, the vaccine uses the genetic molecule mRNA to encode instructions for cells in the body. In this case, it prompts the cells to build hemagglutinin (HA), a protein found on the surface of influenza viruses. Flu viruses use this protein to infiltrate human cells, and it's the same protein targeted by conventional flu vaccines. Following vaccination with mFlusiva, the immune system learns to recognize the HA protein on targeted flu strains, thereby improving its ability to block the viruses from infecting cells.

The ...