Re:Covid herd immunity is probably impossible
by corty on Thursday March 18, 2021 @04:10PM
(#26507037)
I didn't read the original study, but I think the 75 to 95% reduction is in the number of cases, not in viral load. So this would be, in other words, a 75 to 95% prevention.
As to the time the immunity lasts, that remains to be seen. Since it is brand-new, we will only know when new cases from previously-vaccinated people pop up. Maybe it'll be yearly, maybe a booster every 10 years, maybe lifelong. There is research showing that the antibodies from a corona infection last about half a year, but that is not the only factor that may provide immunity. And the yearly flu shot is because the flu virus mutates very rapidly, which corona doesn't as much.
Both of those factors make COVID vaccination quite different from, say, measles vaccination (~97% prevention, lifelong immunity), and seemingly more similar to the flu vaccine, which is not required by any schools (that I know of).