Calculations by the Times suggest that more than a million people could be isolating with coronavirus on Christmas Day given the rapid speed with which the Omicron variant is spreading. It quotes a “downbeat” presentation to top ministers by England’s chief medical officer Prof Chris Whitty, who warned of the “very sharp rise” in Omicron cases and that comfort should not be drawn from suggestion that the strain was less severe or from “unreliable hopes” that infections were peaking in South Africa.