How does the flu shot protect kids?

The best offense during a tough flu season is a good defense. You can protect your family from the flu by ensuring everyone in your household gets a flu shot every year.

But why do you have to get a flu shot every year? How does the flu shot protect you? And how effective is the flu shot this year? Preeti Sharma, M.D., a pulmonologist at Children's Health℠ and Associate Professor at UT Southwestern answers seven common flu shot questions.

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Does the flu shot protect kids?

Yes, the flu shot is an essential tool for protecting kids from the flu. It is designed to stimulate your immune system to make special proteins called antibodies. The standard flu vaccine uses inactivated, "killed" virus particles to cause your body to produce antibodies to the flu virus.

Two weeks after receiving the flu vaccination, your body has enhanced protection from the flu. If live flu viruses enter your body, the antibodies you make after getting the vaccine will help destroy flu viruses before they can make you sick. This prevents you from getting the flu or can make a case of the flu less severe.

Does that mean that getting the flu shot can give you the flu? No, says Dr. Sharma. Because the vaccine is made with inactivated flu viruses, you cannot get the flu from the flu shot. The viruses in the shot are dead and cannot spread or multiply.

Who should get a flu shot?

The flu shot is recommended for everyone 6 months of age and older. The flu shot for kids is the same as the flu shot for adults.

Children 6-months-old to 8-years-old who are getting a flu shot for the first time will need two doses of the flu vaccine.

Your family may especially need a flu shot if someone in your household is at high risk for life-threatening flu complications. People may be at higher risk for flu complications if they are under the age of 5, over the age 65, or if they have:

• Asthma

• Diabetes

• Congenital or Acquired Heart Disease

• Metabolic disorders

• Neurologic conditions

• Neuromuscular disorders

• Chronic lung diseases

Physicians also recommend the flu shot if you or someone in your household is pregnant.

When should you get a flu shot?

Typically, it's best to get the flu shot in early fall. It can take up to two weeks for the antibodies to develop after the vaccine is administered, so it's most effective to get the flu shot before flu season hits. For the 2024-2025 flu season, the Centers for Disease Control and Prevention (CDC) recommends getting the flu shot before the end of October, if possible.

If you miss the early window for getting the flu vaccine, you should still get it. Getting the flu vaccine at any time will help reduce your family's risk of getting sick and the chance of flu-related complications.

How often should you get the flu shot?

It's important to get the flu shot every year. In the first months after you receive the flu shot, you have high levels of antibodies ready to fight off influenza. This is why doctors recommend getting the shot at the beginning of flu season – because you have high levels of protection when the flu is most prevalent.

Over the course of several months, the body's immune response to the vaccination begins to decline. As the flu shot effectiveness wears off, so does a person's protection from the flu. This is why you need a flu shot at the beginning of every flu season.

Because flu viruses are constantly changing, the type of flu you may get can change every year, too. Dozens of viruses cause the flu. Each year, the flu shot contains three or four different types of inactivated flu viruses that may not have been in the flu shot the year before.

Worried you could still get the flu even if you get the flu shot? A 2021 study found that the vaccine reduces severity of illness for people who still catch the flu. People who got the flu vaccine and then contracted the flu are at a 26% lower risk of intensive care unit (ICU) admission and a 31% lower risk of dying from the flu compared to people who did not get the flu vaccine.

"Families may not realize that the flu can cause numerous complications," Dr. Sharma says. "Even though vaccination might not always prevent getting the flu, it does an excellent job of preventing serious complications of the flu like pneumonia, difficulty breathing and death."

Can you get the flu vaccine at the same time as other vaccines?

Yes, you can get your flu shot at the same time as other vaccines. Ask your health care provider if you have any questions.

Is it safe to get the flu shot?

The flu shot is very safe for the general population. Because of the way the vaccine is made, it contains some egg products. However, research shows that the flu shot is safe for people with egg allergies. If you have had a reaction to the flu shot before, you should speak to your doctor.

As with any medical treatment, the flu shot may cause some side effects. Most are mild, such as soreness where the shot was given, headache and fatigue, and only last a few days.

"Mild side effects tell us that the vaccine is doing its job and creating antibodies to fight off the real virus," Dr. Sharma says.

What's the best way to prevent the flu?

Getting a flu shot is the best way to prevent the flu. You should also avoid people who are sick. If you have the flu, stay home from work, school and other public places, especially if you have a fever.

Frequent and proper hand washing is also an important flu prevention strategy. Wash your hands with soap and warm water for 20 seconds, especially before eating or touching your face. Cover up sneezes and coughs with tissues or by putting your face in the crook of your arm. See more tips for helping your family stay flu free.

Learn about flu nasal spray vs. flu shot vaccine options.

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