For most groups, it’s best to get the shot in September or October.
Properly timing your flu shot can help to ensure the vaccine is effective during the peak of flu season.
It takes about two weeks to build your immunity after getting the flu shot.
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This article explains how long a flu shot lasts and why.
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When Should I Get a Flu Shot?
The CDC currently recommends most adults get the flu shot in September or October.
The main exception to the rule is pregnant people in their third trimester.
For everyone else, getting vaccinated earlier in the season is no longer routinely recommended.
If you miss the end of October deadline, though, it’s not too late.
When Should Children Get a Flu Shot?
Children between 6 months and 8 years old should get the influenza vaccine annually in September or October.
When Is Flu Season?
Flu activity can ramp up earlier or later in different parts of the country.
How Long Does the Flu Shot Take to Work?
Flu vaccines work by getting your immune system to produce antibodies to specific strains of the influenza virus.
It takes time for your body to create antibodies, though, and they don’t last forever.
The most common types of seasonal flu, which are also the most serious, mutate quickly.
How Effective Are Flu Vaccines?
The effectiveness of flu vaccines, like their composition, varies from year to year.
Remember, though, that the vaccine is not a guarantee that you won’t get sick.
Even if it works well, it won’t protect you from every illnessonly influenza.
The vaccine only protects against respiratory illness resulting from the influenza virus.
Summary
The flu shot protects against the influenza virus for about six months.
The CDC recommends most adults get the annual flu shot in September or October.
It takes about two weeks after getting the flu shot for it to be fully effective.
But if you get your flu shot too early, its protection may not last through the full season.
However, the timing varies in different parts of the country and can change from year to year.
The influenza vaccine’s effectiveness also varies from year to year.
The flu shot contains three different strains of influenza, which change based on predictions for the upcoming season.
If the predictions are right, the vaccine reduces flu activity by 40% to 60%.
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