Months later, the trio of scientists published a paper that found that a virus, not a novel strain of bacteria like some within the scientific community originally thought, was to blame. Over the following decades, other scientists unfurled the gnarly branches of the large influenza family tree, gathering enough information to formulate a vaccine, which (hopefully) most of us get before every flu season.
But here’s the catch: Influenza is a master shapeshifter. Every year, strains of the virus that infect humans — influenza type A and B — evolve in ways that evade vaccines and, subsequently, our immune systems. This results in uneven vaccine effectiveness from year to year and also undermines efforts to pack a flu shot with a broad, long-lasting immune punch.
But we may have an ace in the hole thanks to mRNA, the same technology used for our Covid-19 vaccines. In a study published Monday in the journal Proceedings of the National Academy of Sciences, researchers at the University of Pennsylvania, Icahn School of Medicine at Mount Sinai, and other institutions have cooked up an mRNA-based influenza vaccine that targets four viral proteins that tend to remain the same across different strains of influenza.
