Quadrivalent Influenza Vaccine

Brand names: AFLURIA Quadrivalent, Fluarix Quadrivalent, FluLaval Quadrivalent, Flucelvax Quadrivalent and Fluzone Quadrivalent, FluMist Quadrivalent

Note: “Prevention and Control of Seasonal Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices — United States, 2019–20 Influenza Season” has been published. CDC recommends annual influenza vaccination for everyone 6 months and older with any licensed, influenza vaccine that is appropriate for the recipient’s age and health status, (IIV, RIV4, or LAIV4) with no preference expressed for any one vaccine over another. Content on this website is being updated to reflect this most recent guidance. More information about the upcoming 2019-2020 flu season is available.

What is quadrivalent flu vaccine?

A quadrivalent influenza vaccine is designed to protect against four different influenza viruses; two influenza A viruses and two influenza B viruses.

Click here to learn more about the vaccine composition for the 2019-20 influenza season.

Why was quadrivalent flu vaccine developed?

For many years, influenza vaccines were designed to protect against three different influenza viruses (trivalent vaccines). Trivalent vaccines include an influenza A (H1N1) virus, an influenza A (H3N2) virus and one influenza B virus. Experts had to choose one B virus, even though there are two different lineages of B viruses that both circulate during most seasons. Adding another B virus to the vaccine aims to give broader protection against circulating influenza viruses.

Who can get quadrivalent flu vaccine?

Different vaccines are approved for different age groups. There is a quadrivalent influenza shot that can be given to children as young as 6 months of age. Other quadrivalent influenza shots are approved for people 3 years and older. More information on approved influenza vaccines for the 2019-2020 influenza season, and age indications for each vaccine are available in CDC’s Table: U.S. Influenza Vaccine Products for the 2019-20 Season.

The quadrivalent nasal spray vaccine is approved for use in non-pregnant individuals, 2 years through 49 years of age. People with certain medical conditions should not receive the nasal spray influenza vaccine.

Who shouldn’t get quadrivalent flu vaccine?


Different influenza vaccines are approved for use in different age groups. In addition, some vaccines are not recommended for certain groups of people. Factors that can determine a person’s suitability for vaccination, or vaccination with a particular vaccine, include a person’s age, health (current and past) and any allergies to influenza vaccine or its components.

Are any of the available flu vaccines recommended over the others?

No. For the 2019-2020 influenza season, CDC and its Advisory Committee on Immunization Practices (ACIP) recommends annual influenza vaccination for everyone 6 months and older with any licensed age-appropriate influenza vaccine including inactivated influenza vaccine (IIV), recombinant influenza vaccine (RIV4) or live attenuated influenza vaccine (LAIV4) with no preference expressed for any one vaccine over another.

How much of the flu vaccines for the United States during 2019-2020 will be quadrivalent?

Most influenza vaccine in the United States is now quadrivalent. Of the 162 to 169 million doses of influenza vaccine projected to be available for the 2019-2020 season, manufacturers estimate that 129 million to 138 million doses will be quadrivalent influenza vaccine.

Are quadrivalent flu vaccines safe?

Yes. Influenza vaccines that protect against four influenza viruses have a safety profile similar to seasonal influenza vaccines made to protect against three viruses, with similar—mostly mild—side effects. Like all seasonal influenza vaccines, vaccines that protect against four influenza viruses are monitored annually for their safety and effectiveness.

Quadrivalent vaccine cannot cause influenza illness because they contain ‘inactivated’ (killed) virus, attenuated (weakened) virus, or influenza virus components that are made using recombinant methods rather than viruses.

For information about influenza vaccine side effects, see “Can the flu vaccine give me the flu?”

What should people do if they can’t find quadrivalent vaccine?

Don’t delay getting vaccinated if you cannot locate a quadrivalent vaccine. The important thing is to get vaccinated against influenza. Find flu vaccine near you using the vaccine finder at http://vaccine.healthmap.org/external icon. Call ahead to ask about availability if you are interested in a specific type of vaccine.

Special Consideration Regarding Egg Allergy

People with egg allergies can receive any licensed, recommended age-appropriate influenza (flu) vaccine (IIV, RIV4, or LAIV4) that is otherwise appropriate.  People who have a history of severe egg allergy (those who have had any symptom other than hives after exposure to egg) should be vaccinated in a medical setting, supervised by a health care provider who is able to recognize and manage severe allergic reactions.