Associated Press

California on Wednesday announced its first confirmed case of the new and apparently more contagious variant of the coronavirus, the second case documented in the United States in a day.

Gov. Gavin Newsom announced the infection found in Southern California during an online conversation with Dr. Anthony Fauci, head of the National Institute of Allergy and Infectious Diseases.

“I don’t think Californians should think that this is odd. It’s to be expected,” Fauci said.

Newsom did not provide any other details about the person who was infected.

The first person in the U.S. known to be infected with the variant was identified Wednesday as a Colorado National Guardsman who had been sent to help out at a nursing home struggling with an outbreak. Health officials said a second Guard member may have it too.

The cases have triggered a host of questions about how the version circulating in England arrived in the U.S. and whether it is too late to stop it now, with top experts saying it is probably already spreading elsewhere in the United States.

“The virus is becoming more fit, and we’re like a deer in the headlights,” warned Dr. Eric Topol, head of Scripps Research Translational Institute. He noted that the U.S. does far less genetic sequencing of virus samples to discover variants than other developed nations, and thus was probably slow to detect this new mutation.

The two Guard members had been dispatched on Dec. 23 to work at the Good Samaritan Society nursing home in the small town of Simla, in a mostly rural area about 90 miles outside Denver, said Dr. Rachel Herlihy, state epidemiologist. They were among six Guard members sent to the home.

Nasal swab samples taken from the two as part of the Guard’s routine coronavirus testing were sent to the state laboratory, which began looking for the variant after its spread was announced in Britain earlier this month, Herlihy said. Samples from staff and residents at the nursing home are also being screened for the variant at the lab, but so far no evidence of it has been found, she said.

The confirmed Colorado case, first announced Tuesday, is in a man in his 20s who had not traveled recently, officials said. He has mild symptoms and is isolating at his home near Denver, while the person with the suspected case is isolating at a Colorado hotel while further genetic analysis is done on his sample, officials said.

The nursing home said it is working closely with the state and is also looking forward to beginning vaccinations next week.

Several states, including California, Massachusetts and Delaware, are also analyzing suspicious virus samples for the variant, said Dr. Greg Armstrong, who directs genetic sequencing at the Centers for Disease Control and Prevention. He said the CDC is working with a national lab that gets samples from around the country to broaden that search, with results expected within days.

The discovery in Colorado has added urgency to the nation’s vaccination drive against COVID-19, which has killed more than 340,000 people in the U.S.

Britain is seeing infections soar and hospitalizations climb to their highest levels on record. The variant has also been found in several other countries.

Scientists have found no evidence that it is more lethal or causes more severe illness, and they believe the vaccines now being dispensed will be effective against it. But a faster-spreading virus could swamp hospitals with seriously ill patients.

The discovery overseas led the CDC to issue rules on Christmas Day requiring travelers arriving from Britain to show proof of a negative COVID-19 test. But U.S. health officials said the Colorado patient’s lack of travel history suggests the new variant is already spreading in this country.