Live Attenuated Influenza Vaccine [LAIV] (The Nasal Spray Flu Vaccine)

Brand name: 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 flu viruses does the nasal spray vaccine protect against?

All nasal spray influenza vaccines for the 2019-2020 season will contain four influenza viruses: an influenza A (H1N1) virus, an influenza A (H3N2) virus and two influenza B viruses.

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

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.

Who can be vaccinated with the nasal spray flu vaccine

The nasal spray 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 should not be vaccinated with the nasal spray flu vaccine?

Some people should not get the nasal spray influenza vaccine:

  • Children younger than 2 years
  • Adults 50 years and older
  • Pregnant women
  • People with a history of severe allergic reaction to any component of the vaccine or to a previous dose of any influenza vaccine
  • Children 2 years through 17 years of age who are receiving aspirin- or salicylate-containing medications.
  • People with weakened immune systems (immunosuppression)
  • Children 2 years through 4 years who have asthma or who have had a history of wheezing in the past 12 months.
  • People who have taken influenza antiviral drugs within the previous 48 hours.
  • People who care for severely immunocompromised persons who require a protected environment (or otherwise avoid contact with those persons for 7 days after getting the nasal spray vaccine).

In addition, the following conditions are precautions to the use of the nasal spray influenza vaccine:

  • Asthma in people aged 5 years and older.
  • Other underlying medical conditions that can put people at higher risk of serious influenza complications. These include conditions such as lung disease, heart disease (except isolated hypertension), kidney disease (like diabetes), kidney or liver disorders, neurologic/neuromuscular, or metabolic disorders. See “People at High Risk of Developing Flu–Related Complications.”
  • Moderate or severe acute illness with or without fever.
  • Guillain-Barré Syndrome within 6 weeks following a previous dose of influenza vaccine.

How effective is the nasal spray seasonal flu vaccine?

Influenza vaccine effectiveness (VE) can vary from year to year, among different age and risk groups, by vaccine type, and even by virus type and subtype. Prior to the 2009 influenza pandemic, the nasal spray vaccine was found to be effective against different influenza viruses.  After the 2009 pandemic, several U.S. studies among 2 through 17-year-olds found that the nasal spray vaccine was effective against influenza B viruses, and was similarly effective against H3N2 viruses as inactivated influenza vaccines, but was less effective than inactivated influenza vaccines against the 2009 pandemic H1N1 viruses, leading ACIP and CDC to recommend against use of the nasal spray vaccine in 2016.

Since the 2017-2018 season, the manufacturer of nasal spray vaccine has used new H1N1 vaccine viruses in production. Some data suggest this will result in improved effectiveness of against H1N1. However, no U.S. studies have evaluated effectiveness of this updated vaccine component against H1N1 viruses. ACIP and CDC voted to resume the recommendation for the use of nasal spray vaccines based on evidence suggesting that the new H1N1 component will result in improved effectiveness of the vaccine against these viruses. There is no expressed preference for any influenza shot or the nasal spray vaccine.

The nasal spray vaccine is an important option for providers, patients and parents in the U.S. and other countries where it continues to be recommended. For more information about vaccine effectiveness, visit How Well Does the Seasonal Flu Vaccine Work?

Should the nasal spray flu vaccine be given to patients with chronic diseases?

LAIV is not recommended for people with some kinds of chronic health conditions because the safety and effectiveness of this vaccine in people with those conditions has not been established.

See Prevention and Control of Seasonal Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices (ACIP) – United States, 2015-2016 Influenza Season – August 7, 2015 for a list of contraindications and precautions for the nasal spray vaccine.

Should pregnant and postpartum women avoid contact with people who were recently vaccinated with the nasal spray vaccine?

Pregnant and postpartum women do not need to avoid contact with persons recently vaccinated with the nasal spray influenza vaccine. However, the nasal spray influenza vaccine should not be given to women who are pregnant. Postpartum women can receive an influenza shot or the nasal spray influenza vaccine.

Are there any contraindications to giving breastfeeding mothers the nasal spray vaccine?

Breastfeeding is not a contraindication for the nasal spray vaccine. Breastfeeding mothers younger than 50 years can get the nasal spray influenza vaccine as long as they do not have any contraindication to getting that vaccine. See Prevention and Control of Seasonal Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices (ACIP) – United States, 2015-2016 Influenza Season – August 7, 2015 for a list of contraindications and precautions for the nasal spray vaccine.

Can the nasal spray flu vaccine be given to patients when they are ill?

The nasal spray influenza vaccine can be given to people with mild illnesses (e.g., diarrhea or mild upper respiratory tract infection with or without fever). However, nasal congestion might limit delivery of the vaccine to the nasal lining. Delaying vaccination with LAIV until the nasal congestion is reduced or use of an age-appropriate injectable vaccine instead of LAIV should be considered. People with moderate or severe illness, with or without fever, should generally wait to be vaccinated until they have recovered. Your health care provider can provide advice about when to get vaccinated if you are feeling ill.

Can nasal spray flu vaccine give me influenza?

Influenza vaccines do not cause influenza illness. The nasal spray influenza vaccine does contain live viruses. However, the viruses are attenuated (weakened), so that they will not cause influenza illness. The weakened viruses are also cold-adapted, which means they are designed to only multiply at the cooler temperatures found within the nose. The viruses cannot infect the lungs or other areas where warmer temperatures exist.

While an influenza vaccine cannot give you influenza illness, there are different side effects that may be associated with getting an influenza shot or a nasal spray influenza vaccine.

These side effects are mild and short-lasting, especially when compared to symptoms of bad case of influenza.

What are the side effects that could occur?

The viruses in the nasal spray vaccine are weakened and do not cause severe symptoms often associated with influenza illness. In children, side effects from the nasal spray may include:

  • Runny nose
  • Wheezing
  • Headache
  • Vomiting
  • Muscle aches
  • Fever (low grade)

In adults, side effects from the nasal spray vaccine may include:

  • Runny nose
  • Headache
  • Sore throat
  • Cough

If these problems occur, they begin soon after vaccination and usually are mild and short-lived. People sometimes faint after medical procedures, including vaccination. Tell your provider if you feel dizzy or have vision changes or ringing in the ears. Rarely, people can experience a severe allergic reaction after an influenza vaccine (or any vaccine); there are about 1-2 cases of severe allergic reactions per million influenza vaccine doses administered and these reactions can be treated with medication. People who think that they have been injured by an influenza vaccine can file a claim with the National Vaccine Injury Compensation Program (VICP)external iconexternal icon.

More information about the safety of influenza vaccines is available at Influenza Vaccine Safety.

Note: There is no recommendation for pregnant women or people with pre-existing medical conditions to get special permission or written consent from their doctor or health care professional for influenza vaccination if they get vaccinated at a worksite clinic, pharmacy or other location outside of their physician’s office. For more information, visit Misconceptions about Seasonal Flu and Flu Vaccines.