Flu vaccine may not be as effective in the oldest old.
About 90% of the estimated 36,000 people who die from flu-related causes in the U.S. each year are 65 and older-it's a mark of how older adults' weaker immune system leaves them vulnerable to infection, and reduces their ability to make antibodies in response to the flu vaccine. A study presented at the Interscience Conference on Antimicrobial Agents and Chemotherapy/Infectious Diseases Society of America annual meeting in October 2008 suggests that a dose four times larger than the standard flu vaccine boosts the amount of antibodies in older adults' blood. The larger dose was given to 2,575 of the 3,837 study participants and generally resulted in 1.5 to twice as many flu antibodies. No studies have yet shown if this translates into fewer cases of severe flu, and this will need to be done before the larger dose of the vaccine will be given to older adults. Meanwhile you'll still benefit from the standard vaccine. Protect yourself further by encouraging your close family to get vaccinated along with any caregivers or friends with whom you regularly come into contact.