High-dose Vaccine
A high-dose vaccine (Fluzone High-Dose) 4x the strength of standard flu vaccine was approved by the FDA in 2009. This vaccine is intended for people 65 and over, who typically have weakened immune response due to normal aging. The vaccine produces a greater immune response than standard vaccine, but it is not yet known whether it provides greater protection against flu. Study results are expected in 2012. CDC recommends the high-dose vaccine for people 65 and over but expresses no preference between it and standard vaccine.
Read more about this topic: Influenza Vaccine