Omicron variant of COVID-19 found in multiple US states

The omicron variant of COVID-19, which had been undetected in the U.S. before the middle of this week, had been discovered in at least five states by the end of Thursday, showing yet again how mutations of the virus can circumnavigate the globe with speed and ease.

A Colorado woman who had recently traveled to southern Africa, a Hawaii resident with no recent travel history, and another California resident who traveled to South Africa last month also were infected by the variant, officials said.

Much remains unknown about omicron, including whether it is more contagious, as some health authorities suspect, whether it can thwart vaccines and whether it makes people as sick as the original strain.