|Articles|March 2, 2018

2018-2019 Flu Vaccine Strains Recommended by FDA

The US Food and Drug Administration (FDA) has weighed in on the strains to be included in the 2018-2019 influenza vaccine.

One week after the World Health Organization (WHO) published their recommendations on the strains to be included in quadrivalent vaccines for use in the 2018-2019 northern hemisphere influenza season, the US Food and Drug Administration (FDA) weighed in with their vote as confirmed by a Vaccines and Related Biological Products Advisory Committee member to Contagion®.

The following strains will be included in the 2018-2019 trivalent vaccine:

  • Influenza A/Michigan/45/2015 (H1N1)pdm09-like virus
  • Influenza A/Singapore/INFIMH-16-0019/2016 (H3N2)-like virus Replaces A/Hong Kong/4801/2014 (H3N2)-like virus from the 2017-2018 northern hemisphere influenza vaccine
  • Influenza B/Colorado/06/2017-like virus (B/Victoria/2/87 lineage) Replaces B/Brisbane/60/2008-like virus from the 2017-2018 northern hemisphere influenza vaccine

Quadrivalent vaccine addition:

  • Influenza B/Phuket/3073/2013-like virus (B/Yamagata/16/88 lineage)

The WHO acknowledged in their recommendations that the change to include the A/Singapore/INFIMH-16-0019/2016-like virus is the result of the lack of activity against A(H3N2) viruses seen with the “egg-propagated A/Hong Kong/4801/2014 (H3N2)-like virus” included in the 2017-2018 vaccine. The WHO found that “recent A(H3N2) viruses were better inhibited by ferret antisera raised against the egg-propagated reference virus A/Singapore/INFIMH-16-0019/2016 compared to ferret antisera raised against other recent egg-propagated A(H3N2) viruses.”


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