The first United States case of the more contagious coronavirus variant that was initially discovered in Britain was found in Colorado on Tuesday, Gov. Jared Polis said, raising the worrisome possibility that the variant is already well established in the patient’s community — and perhaps elsewhere. “It didn’t teleport across the Atlantic,” said William Hanage, an epidemiologist at the Harvard T.H. Chan School of Public Health . The variant was detected in a man in his 20s with no travel history, Mr. Polis said. The man was in isolation in Elbert County, southeast of Denver, he said. Dr. Hanage said the newly reported case “should not be cause for panic.” But, he added, “it is cause to redouble our efforts at preventing the virus from getting the opportunity to spread,” he said. Scientists are worried about variants but not surprised by them. It is normal for viruses to mutate, […]