The National Institutes of Health has initiated an early-stage clinical trial for a universal flu vaccine based on messenger RNA technology. The vaccine aims to provide protection against a broad range of flu strains and long-term immunity, reducing the need for annual shots. Current flu vaccines vary in effectiveness from year to year, as experts must predict the dominant strains in advance for manufacturers to produce the appropriate shots. The universal flu vaccine aims to address this challenge. Flu vaccines typically reduce the risk of illness by 40% to 60% when well-matched to circulating strains, but effectiveness has sometimes dropped to 19% in mismatched years. In the U.S., flu has caused an annual death toll ranging from 12,000 to 52,000 depending on the strains and vaccine match, as reported by the CDC.
