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I think a lot of people aren't aware of what efficacy actually means, and I was one of the them for a while, maybe still am?
From what I gather, Pfizer saying that their vaccine efficacy of 95% doesn't mean that 5% of the trial participants would got jabbed developed COVID-19. It means that of the trial participants who developed COVID-19, the vaccinated group had a 95% reduction in risk of developing COVID-19, I think.
The numbers:
Primary efficacy analysis demonstrates BNT162b2 to be 95% effective against COVID-19 beginning 28 days after the first dose;170 confirmed cases of COVID-19 were evaluated, with 162 observed in the placebo group versus 8 in the vaccine group
So, 162/170 = 95% and 8/170 = 4.7%
Right? If so, "95% efficacy" doesn't mean that 5% of the people who get vaccinated will get COVID-19. In the trial had 43,000 participants, of whom 21,500 got stuck. Eight developed COVID-19. So that's 8/21,500 = .037%
Yes?
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