Deeper dive below. From the article: ““If you really want true herd immunity, where you get a blanket of protection over the country … you want about 75 to 85 per cent of the country to get vaccinated,” Dr Anthony Fauci, the nation’s top infectious-disease official, told a reporter last week. “I would say even closer to 85 per cent.”” The answer is generally considered to be 1 - (1 / R0). If we assume an R0 of 2.5 for SARS-CoV-2 then herd immunity requires 1 - (1 / 2.5) or 60% immunity. Two factors will complicate this. First, strain B.1.1.7 is probably 1.4 to 1.7 times as easy to spread (R0 of 3.5 to 4.25), thus requiring 71% to 77% immunity to crush spread. Second, even if the total population of a country is at 77% immunity, local variations will mean that some areas or subpopulations will be below that. This means in practice that we probably want 110% of the value or 85% immune. You can see blow for estimates of when that will occur. [https://covid19-projections.com/path-to-herd-immunity/](https://covid19-projections.com/path-to-herd-immunity/)