Chasing a universal flu vaccine: hitting the virus where it stays the same
Scientists are pursuing a universal flu vaccine that would protect against many influenza strains by targeting conserved parts of the virus; multiple candidates are in trials using approaches such as focusing the immune response on the virus's stable cone of haemagglutinin, exposing fixed regions by presenting thousands of HA variations, blocking neuraminidase, stimulating T cells, or nasal delivery, and some work also explores AI-assisted strain selection. While a true universal vaccine may take years, interim gains include more durable protection and higher-dose shots for older adults, with experts optimistic about improvements within about five to ten years.