The UK coronavirus strain has spread to at least 60 countries, the World Health Organization reported Wednesday, after the incoming US president Joe Biden led a moving tribute to 400,000 American victims.
Covid-19 has claimed more than two million lives globally since it was first detected in the Chinese city of Wuhan more than a year ago, while the total number of reported cases is edging towards 100 million, according to a Johns Hopkins University tally.
The arrival of mass inoculation drives in the United States, Europe and Asia had brought hope that the end of the epidemic was in sight.
But deep concern over new variants of the deadly pathogen has triggered governments around the world to toughen constraints on restriction-weary populations as officials grapple with how to slow infections until vaccines become widely available.
In its weekly update, the WHO announced the strain first found in the UK was now in 10 more countries than seven days ago.