The thing about variants, they're different. They're mutations. It's so difficult to come up with a vaccine that can keep up with the mutations.

The influenza vaccine teaches the body to produce antibodies against the head of the virus's surface protein, hemagglutinin (HA). Those antibodies ideally prevent HA from attaching to cellular receptors, thwarting infection. But HA's head is highly mutable, which is why vaccinemakers must come up with a new formula every year.

In the case of covid, they're promoting variants as a reason to get old vaccines that were created for a different version of covid.

Stated another way, the very thing that makes influenza vaccines worthless (mutations) is being promoted as a reason to get covid vaccinations ... even though older vaccines wouldn't likely be effective against mutations.