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Flu shot length of effectiveness
An_248483 posted:
I had my flu shot in mid-September at the local pharmacy. My doctor says that I received it too early and that flu shots are only effective for six months. He says that I need a booster in March. Is this correct?
Rod Moser, PA, PhD responded:
The flu shot is considered effective for the entire flu season, which tends to end in the spring (march or April), so yes, that is about six months. However, unless your area has a particularly late flu season, I don't think you took it too early, nor do I necessarily feel that you will need a booster in March. Wait until spring and make that decision then. I am only getting one, and I got it at the end of September.

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