MF59 and AS03 are preparations of squalene (“SKWAH-leen”) that intensify variants of this product respectively developed by Novartis and GSK. COVID-19 removed the need for this product to address both the Yamagata and Victoria lineages. Deployment of an early iteration of this product coincided with a fourfold increase in Guillain–Barré (“ghee-LAN bah-RAY”) syndrome. Individuals with albumin allergies can use this product even though it is primarily produced in the allantoic cavity of fertilized chicken eggs. This product does not need a cold chain because it is the most prevalent product in the US to use thimerosal. This product is either trivalent or tetravalent to account for antigenic shift. For 10 points, name this product made available every winter to address endemic strains of H3N2 and H1N1. ■END■
ANSWER: seasonal flu shot [or influenza vaccine; or flu vaccines; accept vaccines against swine flu or avian flu; accept vaccines against H1N1 or H3N2 until “H3N2” is read; prompt on vaccines or shots] (Influenza B/Yamagata went extinct after 2020 quarantining.)
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= Average correct buzz position