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Frequently Asked Questions

Kids Line Up HeadlineWho should get vaccinated against influenza?
The Centers for Disease Control and Prevention’s (CDC) Advisory Committee on Immunization Practices (ACIP) recommends annual influenza vaccination for all individuals age 6 months and older. Vaccination is the best way to prevent contracting the virus. Influenza vaccines are safe and effective and are the primary means for preventing influenza and its complications.

What types of vaccines are available?

The injectable vaccine includes inactivated (“killed”) influenza viruses and is administered with a needle, usually in the arm. It cannot cause influenza and is approved for use in anyone age 6 months and older, including healthy people, pregnant women, and people with chronic medical conditions.

Who should not get vaccinated against influenza?
Individuals who have had a severe reaction (e.g., anaphylaxis) to eggs or egg proteins, a previous influenza vaccine-associated allergic reaction, or who have ever developed Guillain-Barré syndrome (GBS) after getting an influenza vaccine, should avoid immunization. People with acute febrile illnesses (high fever) should usually wait until their symptoms subside.

Certain groups should not receive the nasal vaccine, including persons younger than 2 years of age, those 50 years and older, children or adolescents taking aspirin, pregnant women, and individuals with certain underlying medical conditions, such as asthma, diabetes, or those who are immunocompromised.

Where can individuals get vaccinated?
Many healthcare professionals administer the vaccine. Local hospitals, health clinics, retail stores, and some employers may also hold vaccination clinics. To find a clinic, use the Vaccine Finder tool at

When should individuals get vaccinated against influenza?
In the United States, the influenza season may begin as early as October and end as late as May. The best time to receive influenza vaccination is before exposure to the virus. Getting vaccinated as soon as vaccine is available each season is recommended, as it typically takes two weeks to be protected after vaccination. Getting vaccinated any time throughout the fall and winter is beneficial.

How long does influenza vaccine protection last?
As influenza strains can change each season, the vaccine is effective only for the current season, so it is important to get vaccinated every year.

How many vaccinations are necessary to be protected?
An annual vaccination is all that is needed to protect against influenza, except for children age 6 months through 8 years who are receiving influenza vaccination for the first time. These children require two vaccine doses, at least one month apart for the injectable vaccine to ensure the best chance of being protected. Parents and caregivers should talk to their child’s pediatrician or other healthcare professional about how many doses their child needs.

Is the influenza vaccine the same every year?
Circulating influenza viruses usually change from year to year. Because of this, a new vaccine is made each year to protect against the current strains. The influenza vaccine is effective only for the current season, so it is important to get vaccinated and to vaccinate patients every year.

Will annual influenza vaccination protect individuals from avian influenza?

The annual seasonal influenza vaccine does not provide protection against avian influenza. Seasonal influenza continues to pose a far greater danger to individuals in the United States than avian influenza.

Can the influenza vaccine actually cause influenza?
The injectable vaccine is made from an inactivated, or killed, virus and cannot transmit infection. This vaccine is licensed for use in all persons 6 months of age and older, regardless of health status.

The nasal-spray vaccine contains live, attenuated viruses and, therefore, has a potential to produce mild signs or symptoms related to influenza virus infection, but it does not cause influenza. The vaccine is licensed for use in healthy persons age 2 to 49 years.

Are there side effects to the influenza vaccine?
The most frequent side effect of the injectable influenza vaccine is soreness at the injection site for one to two days. Occasionally, some people experience a period of mild fever and fatigue for a day or two, following immunization. The most common side effect of the nasal-spray vaccine is runny nose. Other side effects include cold-like symptoms, such as headache, cough, sore throat, tiredness or weakness, irritability, and muscle aches.

Children and Vaccination

Why is vaccinating children a priority?
Influenza is a serious and potentially deadly disease that spreads very easily. Anyone can get influenza, but rates of infection are highest among children. Widespread vaccination of children may interrupt influenza transmission to others, since influenza outbreaks usually begin in children and then move to the community at large.

Is the influenza vaccine safe for use in infants and young children?
Vaccination is safe and effective and currently recommended for all individuals age 6 months and older.

Should children with chronic medical conditions, like asthma or diabetes, receive an influenza vaccination?
Vaccination can be beneficial to both children and adults with certain chronic conditions like asthma, diabetes, heart disease, or who are immunocompromised because infection with influenza can exacerbate these conditions. In addition, individuals with chronic conditions are at increased risk for serious complications of influenza.

The injectable vaccine is approved for use in people at least 6 months of age, including healthy people, pregnant women, and people with chronic medical conditions. The nasal-spray vaccine is licensed for use in healthy people age 2 to 49 years who are not pregnant.


Additional Resources

Freddie the Flu Detective

NFID public service announcement (:30 animated video) providing information on how to detect, prevent, and treat the flu