Several flu vaccine formulations are approved for use in people 65 and older, including two “enhanced” flu vaccines: the high-dose flu vaccine and the adjuvanted flu vaccine, both of which are designed to create a stronger immune response in people 65 years and older. Also, a recent study showed that recombinant flu vaccine can produce a stronger immune response in people 65 years and older. Additionally, there are standard dose flu vaccines that can be used in people 65 and older. It’s important to note that CDC does not have a preferential recommendation for any flu vaccine over another, and vaccination should not be delayed for a specific vaccine product when another vaccine licensed for use in people 65 and older is available.