> You don’t need 100% efficacy to achieve herd immunity (obviously I’m not an epidemiologist and my terms are imprecise) if you have a sufficiently vaccinated population.
Treshold of herd immunity depends on transmitability. For delta variant, if r=6 estimates are true, you would need 100% of population vaccinated in last 5 months (because after that infection immunity drops too low).
The Delta variant is so contagious that there will be no significant herd immunity effect.
https://www.businessinsider.com/delta-variant-made-herd-immu...
I generally agree that we should depart from a covid zero strategy, but not because the vaccines aren’t effective; rather, because too many people are making decisions based on FUD and there doesn’t seem like much that can be done about that in the sort of timeframe during which a “covid-zero” strategy might work.