Abstract：Influenza virus infections are a major public health concern and cause significant morbidity and mortality worldwide. Prevention of influenza through vaccine development is the most effective management strategy, but it is challenged by the evolution of influenza virus variants that could help viruses evade human immunity. Furthermore, the licensed influenza vaccines only induce strainspecific immunity and cannot provide reliable protection against unexpected pandemics and epidemics caused by antigen drift or shift variants. Therefore, research and development of universal vaccines which induce broadspectrum immune responses has become a hotspot. The discovery of broadly neutralizing antibodies has provided new insights into vaccine development for the past years, and the lucubration of conserved antigenic regions and the study of cellular immunity and the optimization of vaccine immunization strategy also promote the development of universal influenza vaccine. This review summarizes the encouraging scientific advances in the field with a focus on novel epitopebased approaches in vaccine design.
