Can someone familiar with flu strains and vaccines help with interpreting the CDC and FDA websites? Basically I’m remembering last year when flu shots were supposedly just 30% effective and wondering whether the flu shots that family members and I had last month are effective against the viruses going around right now. And I just realized that one of my kids was away at college and probably didn’t get a shot.
The CDC site says that these are the strains going around:
Nationally influenza B/Victoria viruses have been reported more frequently than other influenza viruses this season followed by A(H1N1)pdm09.
And the FDA says:
The committee recommended that the trivalent formulation influenza vaccines for the U.S. 2019-2020 influenza season contain the following:
an A/Brisbane/02/2018 (H1N1)pdm09-like virus;
an A/Kansas/14/2017 (H3N2)-like virus;
a B/Colorado/06/2017-like virus (B/Victoria lineage).
The committee also recommended that quadrivalent influenza vaccines contain the above three strains and the following additional B strain:
a B/Phuket/3073/2013-like virus (B/Yamagata lineage)
https://www.fda.gov/vaccines-blood-biologics/lot-release/influenza-vaccine-2019-2020-season
I bolded what look to me like matches between virus strains currently going around and strains in the shots. But I don’t know enough about flu strain classifications to know if these really are matches or not.