The new, more contagious variant of the coronavirus that originated in the United Kingdom may already be here in Massachusetts.
California announced the nation’s second confirmed case of the mutated strain of COVID-19 on Wednesday. That came 24 hours after word of the first reported U.S. variant infection, which emerged in Colorado.
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The cases 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 country.
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 of the new strain in the U.S. has added urgency to the nation’s vaccination drive against COVID-19, which has killed more than 340,000 Americans.
Britain is seeing infections soar and hospitalizations climb to their highest levels on record. The variant has also been found in several other countries.
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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.
"Both Pfizer and Moderna said they don't believe this variant would have any less of an impact on the ability of their products to work," he said. "It is really the primary issue is not the strength of the new strain, it's the contagiousness. Obviously, the rules of the game we've talked about generally would apply, new contagion or not."
Health and Human Services Secretary Marylou Sudders added that the Centers for Disease Control and Prevention are monitoring the situation very closely, and giving guidance to states.
"It's highly, highly contagious, so we just assume that as we know we have community transmission in Massachusetts, we need everyone to engage in those good public health measures we know are effective," she said.
Even before it was discovered in Colorado and California, experts told NBC10 Boston last week that the new COVID strain was probably already in the U.S.
"I can’t imagine it wouldn’t be," said Dr. Shira Doron, a hospital epidemiologist at Tufts Medical Center. "Would I expect to see that variance in the U.S.? Of course. People are traveling all the time. I would expect to see that."
As for the potential impact now that it's here? Medical experts said it's too early to know.
"The implications for how readily it spreads versus what’s going to happen here in the U.S. – it’s really too soon to say," said Dr. Paul Sax, clinical director of the division of infectious diseases at Brigham and Women's Hospital. "It’s something we need to keep watching closely and let virologists do their appropriate research."