Each year, millions of Americans get the flu (influenza). Most people have muscle aches, chills and a fever for a week or so, but some get much sicker and end up in the hospital.
High risk of serious illness and death is greatest for:
- Children younger than 5 years old (especially children 2 or younger)
- Older adults
- Pregnant women
- People with certain health conditions.
Luckily, the flu vaccine can prevent most cases of flu. The Centers for Disease Control and Prevention (CDC) recommends everyone 6 months of age and older get the flu vaccine each year.
There are two types of vaccines against the flu.
- The flu shot, which contains killed virus. Most people are OK to get the flu shot.
- The nasal spray flu vaccine, which is made with live, weakened flu viruses. The nasal-spray flu vaccine is an option only for healthy people 2-49 years of age who are not pregnant.
Who should get a flu shot?
The flu shot is approved for people 6 months of age and older. This includes healthy people and people with chronic medical conditions.
Who should not get the flu shot?
Children younger than 6 months of age should not get the flu shot. (The best way to protect them is be sure people around them are vaccinated for the flu.)
You should not get the flu shot if you have ever had a serious allergic reaction to eggs or a previous dose of flu vaccine.
Talk to your doctor if you have a history of Guillain-Barre syndrome, a severe paralytic illness. Your doctor can help you decide if the shot is a good idea for you.
If you are moderately or severely ill at the time the shot is scheduled, wait until you recover before getting a flu shot.
When should I get vaccinated?
Get the flu shot as soon as it becomes available, which is generally in the early fall. The flu seasons are unpredictable and it takes about two weeks after you get the flu shot for your body to become fully protected.
Some kids between 6 months and 8 years of age require two doses of the flu vaccine. The shots are given about one month apart. Children in this age group who are getting vaccinated for the first time will need two doses. Some children who have received influenza vaccine previously will also need two doses. Check with your child's doctor, they can tell you whether two doses are recommended for your child.
Other children will need only one flu shot this year.
Why do I need a flu shot every year?
The flu viruses change from season to season. Each year the flu vaccine is updated to include the three influenza viruses that research indicates will be the most common for the current flu season.
Can the shot prevent all cases of the flu?
The flu vaccine is highly effective, but no vaccine works 100 percent of the time. If you do get the flu after being vaccinated, you will probably have a milder illness than if you had not gotten the shot.
Remember, the flu shot protects only against the flu. It does not prevent colds and other causes of illness.
What are the risks of the flu shot?
The flu shot may cause mild side effects, such as soreness, redness or swelling at the site of the injection. Serious side effects, such as a severe allergic reaction, are very rare.
Can I get the flu from the shot?
The flu shot is a "killed vaccine" and does not cause the flu.
Is there more than one type of flu shot available?
There are three different types of flu shots:
- The regular flu shot, which is available for people 6 months of age and older.
- The intradermal vaccine is available in some areas for people age 18-64. The intradermal shot is injected into the skin rather than the muscle. It uses a smaller needle.
- A higher-dose flu vaccine is available for people over age 65. The higher dose of vaccine is supposed to give older people better protection.
Talk to your doctor to learn more about these options and to find out what is right for you.
Created on 11/06/2001
Updated on 10/15/2012
- Centers for Disease Control and Prevention. Seasonal influenza.
- Centers for Disease Control and Prevention. Live, intranasal influenza vaccine 2012-2013: What you need to know.
- Centers for Disease Control and Prevention. Inactivated influenza vaccine 2012-2013: What you need to know.