The flu shot isn't really all that foolproof as it is. The reason it's deaths vary year to year so greatly is because we're basically forecasting what strains are going to be big that year. When the deaths climb, it's essentially done much less that year.
There is very much no evidence there are different Covid-19 strains. I've heard there's been some hypotheses that it's evolving to transmit through air more easily or something, but A) I don't know how much merit there are to those claims and B) even if true that doesn't mean it's a unique strain that requires a different vaccine.
What you might be thinking is the pants-on-head argument people (certain Fox News hosts notably) made very early on when we were referring to it more as "coronavirus" than "Covid-19 that there are many things that are "coronaviruses" because that's basically just describing a virus shape (which is technically true), so therefore that means it was nothing to worry about (which is very much not true or even a logical conclusion to draw in any way).
Negative. I am referring to the studies that said 3 strains hit people. The one that hit the USA was deadlier. The Chinese one was less deadlier. And, that they were unsure if people who got a strain were immune to other strains because one of the supposed double positives was infected by two different strains (and some supposedly could be infected by more than 1 strain at the same time).
That said, again, I am not arguing anything is deadlier than the other. I am saying you have to compare similar scenarios to one another to make a comparison.
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Xbox Live User Name - Corrik Currently playing: Spider-Man (PS4), Quantum Break (X1)