Molecular model of SARS-CoV-2 coronavirus spike (S) protein (red) with variants B.1.531 and B.1.1.7 highlighted mutation sites. S proteins are found in the viral membrane, bind to angiotensin 2 conversion enzyme receptors (ACE2, blue) on host cell membranes, and facilitate virus entry into the cell.
Juan Gaertner | Getty Images Scientific Photo Library
The highly contagious variant first identified in the UK is now the most common Covid strain circulating in the United States, the head of the Centers for Disease Control and Prevention said on Wednesday.
The variant, known as B.1.1.7, is “now the most common offspring circulating in the United States.” CDC Director Dr. Rachelle Walensky said during a White House briefing. Testing remains an important strategy for the rapid identification and isolation of infectious people, including those with concerns, Walensky said.
The UK has identified B.1.1.7, which appears to be more deadly and spread more easily than other strains, last autumn. Since then, it has spread to other parts of the globe, including the United States, which has identified 16,275 cases in 52 jurisdictions since Tuesday, according to the CDC.
Florida has the most confirmed cases of the new variant, according to a CDC data map, closely followed by Michigan, Wisconsin, California and Colorado. Public health officials say they are working as soon as possible to identify more cases.
Last week, Walensky said that strain B.1.1.7 is beginning to become the predominant strain in many regions of the United States, accounting for 26% of Covid-19 cases circulating across the country. She urged the public to continue security measures against the pandemic, such as washing hands, wearing masks and practicing social distance.
“This is a critical moment in our fight against the pandemic,” Walensky said last week. “We can’t afford to let our guard down.”
The number of coronavirus cases remains far from their January highs, but slightly above the most recent low point in late March. The seven-day average of new daily cases is 64,700, according to data compiled by Johns Hopkins University, a level similar to what the country saw during summer growth.
Even as vaccination rates increase, highly contagious variants are spreading rapidly and could hinder the nation’s recovery from the pandemic.
Walensky said Wednesday that the United States needs to step up its vaccination efforts, which have averaged about 3.1 million photos a day since Monday. Tuesday, President Joe Biden announced that states should open Covid-19 vaccine programming for all US adults by April 19, raising the initial deadline by almost two weeks.
“We must continue to vaccinate as many Americans as possible every day,” Walensky said, adding that it will cause new cases and deaths.
– Nate Rattner of CNBC contributed to this report.