[apatters]

Both of these comments are spreading misinformation about "herd immunity."

Any amount of immunity or resistance within the population will reduce the effective reproduction rate of the virus. This effect becomes more significant as the immunity rate increases.

Herd immunity is a colloquial term which refers to the point where there's so much immunity that the effective reproduction rate <1 and new infection clusters die out. The percentage of the population which needs to be immune to get R<0 depends on many factors, consider that many countries have managed to achieve this with near zero population immunity.

For example - if we imagine a hypothetical society which could indefinitely maintain measures like social distancing and mask wearing, the effective reproduction number will be low to begin with; the population immunity required to get to R<0 will therefore be lower.

Please start here before spreading additional misinformation: https://en.wikipedia.org/wiki/Basic_reproduction_number