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Vial of flu vaccine in front of a syringe and another vial


Influenza vaccines, commonly called "flu shots" help protect against getting severe influenza from the flu viruses that are expected to be most common during the upcoming year's flu season. For the 2021-2022 flu season, all available influenza vaccines are "quadrivalent," meaning they protect against two different influenza A viruses and two different influenza B viruses.

However, quadrivalent flu vaccines differ in how they are made and what they contain, and this can impact their efficacy and appropriateness for different people. They may contain live attenuated virus (FluMist), inactivated virus (Afluria, Fluarix, FluLaval, Fluzone and Fluzone High-Dose, Fluad, and Flucelvax), or recombinant viral protein (Flublok).

Sign in to learn how these differ and which are most suitable for older people, as well as those with egg allergy, and find out where to get a vaccine and what the cost might be (if, for example, you don't have insurance).

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