Live, Attenuated Influenza Vaccine: Is Past Performance a Guarantee of Future Results?

PURPOSE:

Live, attenuated influenza vaccine (LAIV) has had a tumultuous recent history that can be difficult for many to follow and understand. This commentary reviews the origin of LAIV; the events and circumstances that led to the withdrawal of any recommendation pf LAIV use in the United States; the merits, shortcomings, and repercussions of that decision; and finally some thoughts about the future of LAIV.

METHODS:

[List of databases, eg, PubMed] were searched for relevant articles. The reference lists of identified articles were searched manually for additional papers eligible for inclusion.

FINDINGS:

Prior to 2013, LAIV had a record of accomplishment of providing equal or greater protection against influenza in children. Since 2013, concerns about the lack of protection with LAIV against pandemic H1N1 strains led to the withdrawal of any recommendation of its use in the United States by the Advisory Committee on Immunization Practices. After some significant changes to the content, evaluation, and production of LAIV, it has been recommended again for use in the United States in the 2018-2019 influenza season.

IMPLICATIONS:

One can debate the merits of whether LAIV should have been removed from use, but it is likely that many years from now, the recent "ups and downs" of LAIV will only be an interesting footnote in history.