The Flu Vaccine: Get the Facts

Medically Reviewed by Jennifer Robinson, MD on February 25, 2024
3 min read

To protect yourself from the flu and stop its spread, you need a flu vaccine. Learn what it is and when to get it to help keep your family well.

The flu shot is a form of the vaccine that you get in your arm. Some years, you can get it as a nasal spray instead. Flu vaccines are made to target three or four types of flu viruses that are most likely to make you sick during the upcoming year.

Almost everyone 6 months old and older should get a flu vaccine every year.

Some people are more at risk of getting very sick from complications of the flu than others. These groups should be sure to get a flu shot each year:

  • Children, especially from 6 months to 5 years old
  • Pregnant women
  • Adults age 65 and older
  • People with health conditions
  • Those who live in nursing homes or other long-term care facilities
  • Certain groups of people, including Native Americans and Alaska Natives
  • Travelers and people living abroad

The following people shouldn’t get a flu vaccine:

  • Children under 6 months old
  • People who are very allergic to the flu shot or any of its ingredients

Talk to your doctor before you get the vaccine if you have any of these symptoms:

  • An allergy to eggs or any of the other ingredients in the vaccine
  • A history of Guillain-Barre syndrome
  • If you’re not feeling well

As soon as it becomes available, by October, if possible. It’s best to get the vaccine before the flu season starts. But you can still get it in January or later.

There are many. Ask your doctor which one will work best for you.

The standard flu vaccine protects you from three different flu viruses. You get this shot in your muscle. If you don’t like needles, your doctor may be able to use a jet injector to give it to you. It’s a high-pressure tool that squirts the medicine into your skin. If you’re age 65 or older, you can get a high-dose flu vaccine. It’s four times stronger than the regular flu shot. Ask your doctor if they have it.

Another type of flu vaccine protects against four different viruses. You can get it as a shot. Some years, the vaccine is also available as a nasal spray. The intradermal flu shot is a very small needle that goes into your skin. You can get this if you’re between ages 18 and 64.

Ask your doctor which vaccine is best for you.

The flu vaccine is the most effective way to prevent the flu. It takes about 2 weeks for it to protect you. 

There’s still a chance you could get the flu after you get vaccinated. That depends on many things, like your age and how healthy you are. It also depends on how closely the vaccine matches the type of flu that is going around. Even if you do get sick, there’s a good chance your illness will be milder. 

Forget what you might have heard. You can’t get the flu from the flu vaccine. But you may have side effects that mimic cold or flu symptoms. Some of these are:

  • Soreness or swelling where you got the shot
  • Aching
  • Nausea
  • Slight fever

The nasal spray vaccine can also cause runny nose, headache, vomiting, fever, wheezing, and muscle aches.

Call 911 if you have any of the following symptoms after you get a flu vaccine. They can be a sign of a severe reaction:

  • High fever
  • Hoarseness
  • Weakness
  • Paleness
  • Dizziness
  • Racing heart
  • Trouble breathing
  • Hives
  • Swelling around the lips or eyes
  • Changes in behavior