It sometimes seems as if Professor Tim Spector, of King’s College London, was conjured up especially to be a walking, talking rebuke to Public Health England.

Where PHE has been lumbering, slow to respond to the fast-moving virus, Spector has been nimble, quick to see opportunity and adapt. This time last year, as Boris was preoccupied with the defining question of his premiership — who could possibly have leaked a disobliging story about his girlfriend’s dog — Tim Spector was concocting a plan for how to collect data about Covid from around the country.