For the 2018–19 influenza season, there are three types of influenza vaccine available in the United States – inactivated influenza vaccine, recombinant influenza vaccine, or live attenuated influenza vaccine. Click
on each type to learn more.
Live attenuated influenza vaccine (LAIV)
LAIV was approved for use in the United States in 2003.
It is given by the intranasal
route. All live attenuated influenza vaccine is quadrivalent (LAIV4) and contains the same four influenza viruses as IIV4. The
live attenuated influenza viruses in LAIV4 are temperature-sensitive.
This means that they are cold-adapted,
so they effectively replicate
in the mucosa
of the nasopharynx,
but are less able to replicate in warmer body areas such as the
lungs. LAIV4 is grown in chicken eggs. Each dose contains residual amounts of egg protein and gentamicin sulfate, but it does not contain thimerosal.
During the 2016–17 and 2017–18 influenza seasons, the Advisory Committee on Immunization Practices (ACIP) recommended that LAIV not be used because of concerns about low effectiveness against influenza A(H1N1)pdm09-like viruses circulating in the United States during the 2013–14 and 2015–16 seasons. On February 21, 2018, ACIP recommended that LAIV be an option for influenza vaccination of persons for whom it is appropriate for the 2018–19 season.