Officials with the CDC's Advisory Committee on Immunization Practices (ACIP) have recommended using the quadrivalent live, intranasal influenza vaccine (Flumist, AstraZeneca) in the US for the 2018-2019 season.
The recommendation follows the presentation of positive results from a US study in children between the ages of 2 to <4 years evaluating the shedding and antibody responses of the H1N1 strain in the live attenuated influenza vaccine.
Study results demonstrated that the new 2017-2018 H1N1 LAIV post-pandemic strain (A/Slovenia) performed significantly better than the 2015-2016 H1N1 LAIV post-pandemic strain (A/Bolivia), which was previously associated with reduced effectiveness. The antibody response induced with the new H1N1 LAIV strain was comparable to earlier data seen with the highly effective H1N1 LAIV strain included in the vaccine before the 2009 influenza pandemic.
The quadrivalent vaccine is approved for use in the US, Canada and the European Union. Limited quantities of the vaccine continue to be available in the US for the current 2017-2018 season.