Offering the influenza vaccine annually to all people over the age of 50 would save around 275,000 quality-adjusted life years over the lifetimes of a birth cohort of 4 million.
Macioesk, Michael V., Leif I. Solberg, Ashley B. Coffield, Nichol M. Edwards, and Michael J. Goodman. Infuenza Vaccination: Health Impact and Cost Effectiveness Among Adults Aged 50 to 64 and 65 and Older. Am J Prev Med. 2006; 31(1): 72-9. http://www.ajpmonline.org/article/S0749-3797(06)00120-6/fulltext