The new and more infectious variant of the coronavirus first detected in Britain has now reached the US—but officials aren't sure how. Health authorities in Colorado say the B117 variant was found in an Elbert County man in his 20s with no recent history of traveling to Britain or anywhere else, the Denver Post reports. Gov. Jared Polis says the man is now in isolation and authorities are conducting contact tracing interviews. Polis says the case was confirmed by the Colorado State Laboratory, which notified the federal Centers for Disease Control and Prevention, reports the New York Times.
"There is a lot we don’t know about this new COVID-19 variant, but scientists in the United Kingdom are warning the world that it is significantly more contagious," Polis said in a statement, per the AP. "The health and safety of Coloradans is our top priority, and we will closely monitor this case, as well as all COVID-19 indicators, very closely." The variant led to a stricter lockdown in Britain and caused dozens of nations to ban flights from the country. B117 has also been detected in countries including Italy, Denmark, and Canada. Authorities say coronavirus vaccines will likely be effective against the variant. The new strain is believed to up to 70% more transmissible, but there is no sign it causes more severe illness. (More coronavirus stories.)