What if herd immunity to coronavirus is closer than scientists thought?

We’ve known from the beginning how the end will arrive. Eventually, the coronavirus will be unable to find enough susceptible hosts to survive, fading out wherever it briefly emerges.
To achieve so-called herd immunity – the point at which the virus can no longer spread because there are not enough vulnerable humans – scientists have suggested that perhaps 70 per cent of a given population must be immune, through vaccination or because they survived the infection.

Now some researchers are wrestling with a hopeful possibility. In interviews with The New York Times, more than a dozen scientists said that the threshold is likely to be much lower: just 50 per cent, perhaps even less. If that’s true, then it may be possible to turn back the coronavirus more quickly than once thought.