When should I get a flu vaccine?

You should get your flu shot or spray today! Flu season usually peaks in January or February, but it can occur as late as May. Early immunization is the most effective, but it is not too late to get the vaccine in December, January or even later.
Dr. Darria Long Gillespie, MD
Emergency Medicine
Flu season tends to peak in January. However, in this video, I will explain why the best time to get your vaccine is in the fall.
The best time to get a flu vaccine is between September and December, before flu season really peaks in January, February or later. But if the new year rolls around and you realize you never got vaccinated, relax, it's not too late to get your flu shot. It usually only takes about two weeks for your body to make antibodies (immune system proteins that help your system recognize the flu virus) to the virus. So no matter when you get vaccinated, you still get some protection.

While a single vaccine lasts the entire season, it won't protect you next year because your immunity fades. Plus, flu viruses change from year to year. That's why it's important to get vaccinated every year.
Zachary Rubin, M.D., an infectious-disease specialist at the David Geffen School of Medicine at UCLA, notes, “Even if you got last year’s shot, you need to get it again.” That’s because the effects of the influenza vaccine wane with time. In fact, for some individuals, the immunity lasts only a few months. For that reason, Dr. Rubin recommends that when feasible, patients wait to get their shot until just before the onset of the flu season. The vaccine becomes available in August or September.
Elizabeth A. Kelly, MD
Allergy & Immunology
The best time to get the vaccine is in October, before the flu season starts. The next best time is in November, but if that is not possible, getting a flu vaccine at anytime during the flu season will still help, even through the spring season. Children under 9 years old who are getting the vaccine for the first time need two doses, one month apart.
The best time to get your flu shot is beginning in September. The shot takes about two weeks to take effect. If you have a cold or other respiratory illness, wait until you are healthy again before having your flu shot.
Getting vaccinated before flu activity begins helps protect you once the flu season starts in your community. It takes about two weeks after vaccination for the body’s immune response to fully respond and for you to be protected -- so make plans to get vaccinated. The Centers for Disease Control and Prevention (CDC) recommends that people get a flu vaccine by the end of October, if possible. However, getting vaccinated later can still be beneficial. The CDC say it’s beneficial to get a flu vaccination as long as influenza viruses are spreading, even if it’s January or later. Children aged six months through eight years who need two doses of vaccine should get the first dose as soon as possible to allow time to get the second dose before the start of flu season. The two doses should be given at least 28 days apart.

The presence of the CDC logo and CDC content on this page should not be construed to imply endorsement by the US Government of any commercial products or services, or to replace the advice of a medical professional. The mark “CDC” is licensed under authority of the PHS.
Diana K. Blythe, MD
You should get the flu shot in the early fall, in order to have protection for the entire flu season. Most people only need one flu shot every flu season.

In children under nine years old who are getting the flu shot for the first time, a booster flu shot is needed a month later to improve the effectiveness of the vaccine. Children nine or older and adults only need one flu shot every flu season.
Influenza ( flu shot ) vaccine is recommended annually in the United States during the fall and winter season to protect against the outbreak of the A, the B, and the H1N1 virus. It should only be given one time and needs to be repeated each flu season.

The flu vaccine is contraindicated if the person is allergic to eggs, has a history of a severe reaction to previous flu shot, or has a history of Guillain-Barre.

If the person is sick with a fever, they should wait till they recover to be vaccinated.

The vaccine is given in a single dose injection, and should not be mixed with any other medicine.

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Vaccines work to protect your body against germs. Because of vaccines, many of the diseases that can cause severe sickness, handicaps and death have been eradicated. Learn more from our experts about vaccines.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.