A man in his 20s in Colorado is confirmed to have the COVID-19 variant that was detected in the United Kingdom, Colorado officials announced Tuesday.
The case appears to be the first known case of that variant in the U.S.
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Colorado officials said the man, who's had no travel history, is in isolation in Elbert County.
"Public health officials are doing a thorough investigation," a press release from the governor's office said. "The individual has no close contacts identified so far, but public health officials are working to identify other potential cases and contacts through thorough contact tracing interviews."
The variants are all the same virus, no matter their small genetic differences.
SARS-COV-2 is a respiratory virus, meaning it is transmitted through droplets, so masks and social distancing still work to slow transmission, no matter the variant.
Earlier this week Dr. Anthony Fauci said the variant strain is something "to follow very carefully."
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European Union nations have banned flights from the U.K. and Germany was considering limiting such flights to make sure that a new strain sweeping across southern England does not establish a strong foothold on the continent.
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British Prime Minister Boris Johnson has said the new variant of the virus is 70% more transmissible than existing strains and appears to be driving the rapid spread of new infections in London and southern England.
"There's no evidence to suggest it is more lethal or causes more severe illness," he said, or that vaccines will be less effective against it.
ABC News and The Associated Press contributed to this report.