Abstract
For older populations, most of whom are women, preventing illnesses and deaths through the use of vaccines is a leading public health challenge. Our understanding about how age and sex affect the immune system is limited, and basic and translational research aimed at improving vaccines and immune responses of older persons is needed. In the meantime, fully implementing current vaccine recommendations, particularly those for influenza and pneumococcal vaccines, can save thousands of lives and prevent illnesses in persons > 50 years of age.