The influenza virus is highly mutable, undergoing frequent genetic changes that can render existing vaccines less effective. Annual flu vaccines are developed based on predictions of the most likely circulating strains, but these predictions are not always accurate. This discrepancy can lead to significant public health challenges, including higher morbidity and mortality rates during flu seasons. A universal flu vaccine would ideally offer protection against all or most influenza strains, reducing the need for yearly vaccinations and improving overall herd immunity.
