Herd immunity, for some definitions of a debated term, is absolutely achievable - and lasting. [0]
> Technically, then, a population can reach herd immunity even with low levels of the pathogen still circulating, which means it hasn't necessarily been eradicated for good. The point, ultimately, is that herd immunity may not be the right shorthand to refer to the end of the pandemic. It’s been bandied about incorrectly, certainly imprecisely, Fine says. “I think people often haven’t a clue what they’re saying.”
> Technically, then, a population can reach herd immunity even with low levels of the pathogen still circulating, which means it hasn't necessarily been eradicated for good. The point, ultimately, is that herd immunity may not be the right shorthand to refer to the end of the pandemic. It’s been bandied about incorrectly, certainly imprecisely, Fine says. “I think people often haven’t a clue what they’re saying.”
[0] https://pmc.ncbi.nlm.nih.gov/articles/PMC8166024/