Nemours





The Flu Vaccine

If you've ever had the flu, you know how bad it can make you feel. To help avoid all that misery — as well as possible health complications — doctors now recommend that all teens get a flu vaccine every year.

Why Get Vaccinated?

The main reason for getting vaccinated is to spare yourself the misery of flu. But there are other reasons to get vaccinated too. 

It's especially important for people with certain medical conditions (like kidney disease, diabetes, HIV, heart problems, or asthma) to get a flu vaccine. They are more likely to have serious complications (like pneumonia) when they get the flu.

Kids and teens who take aspirin regularly also need to be vaccinated. They are at risk for developing a serious condition called  if they get the flu.

Another reason for getting vaccinated is to protect the people around you who might get seriously ill from flu — like babies, people with serious illnesses, and the elderly. When you protect yourself with a flu vaccine, you also protect other people who are more vulnerable because there's less chance you'll get the flu and pass it on. Scientists call this "herd immunity."

When Should a Person Get Vaccinated?

The best time to get a flu vaccine in the United States is before flu season starts. This gives the body a chance to build up immunity before the winter flu season. It's best to get vaccinated as soon as this year's flu vaccine becomes available in your area. (Your mom or dad should be able to find out when that is from your doctor's office, or you can ask your school nurse.)

Even if you can't get vaccinated right away, getting a flu vaccine after flu season begins will still give you some protection. You also can protect yourself against the flu (and many other infections) by washing your hands well and often.

What's in a Flu Vaccine?

Flu vaccines are currently recommended as a shot. The shot contains killed flu viruses that won't cause people to get the flu, but will cause the body to make antibodies to fight off infection by the live flu virus.

The flu shot is very effective at protecting against the flu, but it's not 100%. A few people who get the shot will get the flu. In addition, the shot only contains certain strains of the virus. If a new flu strain emerges, a person who's had a shot may not be protected against it.

There is a nasal spray form of the flu vaccine, but it is no longer recommended by the Centers for Disease Control (CDC), for teens or adults. The nasal spray form did not prevent people from getting the flu between 2013 and 2016. Researchers aren't sure why recent versions of the vaccine no longer work well, but at this time, doctors can no longer recommend the nasal spray version.

What About Side Effects?

It's possible to have some minor side effects for 1 or 2 days after getting a flu shot, like soreness in the area where you got the shot. Some people may feel achy or have a mild fever after getting the shot. But the side effects aren't as bad as the flu, which can make some people sick for as long as 2 or 3 weeks.

If you have an egg allergy, get your flu shot in a doctor's office, not at a supermarket, drugstore, or other venue.

Date reviewed: June 2016

A TeensHealth Education Partner

Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.

© 1995- KidsHealth® All rights reserved.

Images provided by iStock, Getty Images, Corbis, Veer, Science Photo Library, Science Source Images, Shutterstock, and Clipart.com