Rocky Mountain Regional VA Medical Center registered nurse Salek Walker gives a dose of the Pfizer-BioNTech COVID-19 vaccine to Russ Shell, a registered nurse in a COVID unit at the hospital in Aurora, Colorado, US, , on Dec 16, 2020. [Photo/Agencies] WASHINGTON -- A more contagious variant of COVID-19 that was first discovered in Britain was identified in the US state of Colorado on Tuesday, according to the state's governor. It is the first time the variant strain has been identified in the United States, according to media reports. The COVID-19 variant was identified in a Colorado man in his 20s, with no travel history, said Colorado Governor Jared Polis in a statement. The man is in isolation in Elbert County, and will remain in isolation until cleared by health officials, according to Polis. No close contacts of the man have been identified yet, but health officials are working on contact tracing, he said. "The health and safety of Coloradans is our top priority and we will monitor this case, as well as all COVID-19 indicators, very closely," Polis said.