ACIP Recommends Against LAIV in Coming Influenza Season

A statement released by AstraZeneca noted that "the US CDC effectiveness data for 2015-2016 season contrast with studies by AstraZeneca as well as preliminary independent findings by public health authorities in other countries.

Officials with the Advisory Committee on Immunization Practices (ACIP) of the Centers for Disease Control and Prevention (CDC) have recommended against using the FluMist® Quadrivalent Live Attenuated Influenza Vaccine (LAIV) in the United States for the 2016-2017 influenza season. 

The updated guidance stated the vaccine should not be used in any setting, based on CDC vaccine effectiveness data from the last three influenza seasons in the United States, which indicated FluMist Quadrivalent did not demonstrate statistically significant effectiveness in children 2 to 17 years of age.

A statement released  by AstraZeneca noted: “the US CDC effectiveness data for the 2015-2016 season contrast with studies by AstraZeneca as well as preliminary independent findings by public health authorities in other countries.1 2 These findings demonstrate FluMist Quadrivalent was 46% to 58% effective overall against the circulating influenza strains during the 2015-2016 season. As influenza vaccine effectiveness varies from season to season, it is evaluated in annual observational studies. The CDC states that when there is a good match between the strains in the vaccine and those that circulate during the influenza season, vaccines are typically 50% to 60% effective.3 AstraZeneca is working with the CDC to better understand its data to help ensure eligible patients continue to receive the vaccine in future seasons in the United States.”

Recommendations by the ACIP were made following an afternoon of data about influenza vaccines, where the committee heard about vaccine efficacy, as well as safety data. Tom Shimabukuro, of the CDC, told the committee that the percentage of Guillain-Barré syndrome rose slightly last year overall, with two reports of anaphylaxis noted specifically with the LAIV4 vaccine, specifically, egg allergy in an adult and child.

Vaccine manufacturers had projected that as many as 171 million to 176 million doses of influenza vaccine, in all forms, would be available for the United States during the 2016-2017 season. The makers of LAIV had projected a supply of as many as 14 million doses of LAIV/nasal spray flu vaccine, or about 8% of the total projected supply.

The ACIP recommendation must be reviewed and approved by the CDC’s director before it becomes CDC policy. The final annual recommendations on the prevention and control of influenza with vaccines will be published in an upcoming CDC Morbidity and Mortality Weekly Report Recommendations and Reports.


  1. Public Health England. Influenza vaccine effectiveness in adults and children in primary care in the UK: provisional end-of-season results 2015-16.

  2. Nohynek H. Finland Department of Health Protection. Seasonal Childhood Influenza Vaccinations. Presented at: Nordic Vaccine Meeting. April 2016; Reykjavik, Iceland.

  3. CDC. Vaccine Effectiveness – How Well Does the Flu Vaccine Work? CDC Website.