Washington — Dr. Rochelle Walensky, director of the Centers for Disease Control and Prevention (CDC), predicted Sunday that a new strain of the coronavirus that was first identified in the United Kingdom and has since been detected in the U.S. may be the "dominant strain" here by the end of March.
In an interview with "Face the Nation," Walensky said there are more than 1,000 cases of the U.K. variant, known as B.1.1.7, in 39 states.
"We know now that, or we estimate now that about 4% of disease in this country is related to B.1.1.7," she said. "And we have projections that it may be the dominant strain by the end of March."
Public health officials warn the U.K. variant is more transmissible and argue the new strain, as well another identified in South Africa and a third from Brazil, underscores the need for the American people to get quickly vaccinated.
Walensky said pharmaceutical companies are adjusting their science to neutralize the B.1.1.7 variant, and the CDC is watching the epidemiology with people who have already received their coronavirus vaccines.
"But we're not waiting for that," she said. "We're doing the science to scale up different vaccines in case we either need bivalent vaccines, that is a vaccine that has two different strains, or booster vaccines. Both are happening."
While Walensky predicted the U.K. strain could be dominant by the end of next month, she said that should not deter efforts to reopen schools, which is a priority of the Biden administration. The CDC released highly anticipated guidelines Friday for getting children back into classrooms, which included recommendations for phased reopenings based on rates of community transmission. Before taking office, President Biden set a goal of getting most schools reopen in his first 100 days in office.
"What we know from the scientific literature is that most disease transmission does not happen in the walls of the school. It comes in from the community," she said. "There's very limited transmission between students, between students and staff, really, mostly between staff to staff when there are breaches in mask wearing. So what we're really advocating for now is working to get our — especially in the high areas of transmission, the red zones you just talked about — getting our K-5 kids back in a hybrid mode with universal mask wearing and six feet of distancing."
Walensky stressed mitigation strategies, such as mask-wearing and social distancing, are crucial to protecting against the coronavirus strains.
"The B.1.1.7 variant may be less forgiving when we have breaches in these mitigation strategies, but the mitigation strategies are indeed the same," she said.
There have been more than 27.5 million coronavirus cases in the U.S., and the death toll stands at more than 484,000, according to Johns Hopkins University. Walensky previously predicted the nation would see more than 500,000 deaths from COVID-19 by mid-February.
She said Sunday there are still 100,000 cases per day and between 1,500 and 3,500 deaths daily, and warned against relaxing mitigation strategies. Both Montana and Iowa, for example, have lifted their mask mandates.
"We are nowhere out of the woods," Walensky said. "And as you know, if we relax these mitigation strategies with increasing transmissible variants out there, we could be in a much more difficult spot. So what I would say is now is the time to not let up our guard. Now is the time to double down, still with 100,000 cases a day, still with over two and a half times the cases we had over the summer."
Walensky said children need to be back in the classroom and communities back to "some normal functioning" before public health guidelines are eased.