The COVID-19 variant, first detected in Britain, has now spread to more than 50 countries within the space of just over a month.
Nearly 20 European countries have reported cases of the more contagious strain.
Among those hardest hit is Portugal, which has an average infection rate of more than 8,800 in the past seven days.
U.S. health officials are warning the British variant could be its "dominant source" of infection by March.
Three other variants are also troubling -- one identified in South Africa and two in Brazil.