Seasonal influenza is a prevalent and serious annual illness resulting in widespread morbidity and economic disruption throughout the population; the elderly and immunocompromised are particularly vulnerable to serious sequelae and mortality. The changing demographics worldwide to an aging society have important implications for public health policy and pharmaceutical innovations. For instance, primary prevention via immunization is effective in reducing the burden of influenza illness among the elderly. However, the elderly may be insufficiently protected by vaccination due to the immunosenescence which accompanies aging. In addition, vaccine hesitancy among the younger populations increases the likelihood of circulating infectious diseases, and thus concomitant exposure. While it is clear that the development of more immunogenic vaccines is an imperative and worthy endeavor, clinical trials continue to demonstrate that the current influenza vaccine formulation remains highly effective in reducing morbidity and mortality when well matched to circulating strains.

b University of Hradec Kralove Faculty of Science Hradec Kralove Czech Republic

c SUNY Upstate Medical University Department of Pediatrics Division of Pediatric Infectious Diseases Syracuse NY USA

Charles University Faculty of Medicine in Hradec Kralove Department of Social Medicine Hradec Kralove Czech Republic

University of Defence Faculty of Military Health Sciences Hradec Kralove Czech Republic

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Demand and motivation for influenza vaccination among healthcare workers before and during the COVID-19 era: a cross-sectional survey