(Bloomberg) —

A top Biden administration health official warned Americans not to get complacent about rapidly falling coronavirus cases as a potentially more lethal variant spreads in the U.S.

The U.S. has seen more than 1,000 cases of the strain first identified in the U.K., with infections across at least 39 states, said Rochelle Walensky, head of the Centers for Disease Control and Prevention.

It is around 40% to 50% more transmissible, meaning “we’re likely to have more cases and more deaths from this,” and early data “have suggested there might in fact be increased morbidity and mortality,” Walensky said on NBC’s “Meet the Press,” one of three scheduled interviews on Sunday.

Even with more than 52 million vaccines administered in the U.S., the country continues to see close to 100,000 cases per day — although infections, hospitalizations and deaths have declined steadily from January peaks.

About 4% of coronavirus cases in the U.S. are now from the U.K. variant, which public health experts says is expected to become the dominant strain as early as March.

“We are nowhere out of the woods,” and “now is the time to double down,” Walensky said on CBS’s “Face the Nation.” “If we relax these mitigation strategies with increasingly transmissible variants out there, we could be in a much more difficult spot.”


Masks Off

Walensky’s warning comes as some states, including Iowa and Montana, ease mandates on mask wearing and as the CDC emphasizes that tamping down community spread is key to safely reopening schools — a key goal of the Biden administration.

The CDC issued guidance for schools to operate in-person during the pandemic on Friday, with strategies including masks, six feet of social distancing, cleaning of classrooms and rapid contact tracing. Walensky also said vaccinating teachers should be a priority.

While the guidance did not mandate reopening, it said that schools should open “as safely and as quickly as possible,” weighing in on a prickly debate over how to educate children amid the coronavirus crisis that has often put teachers and local school districts at odds.

“Our guidance is really dependent on how much disease is in the community,” since most transmission within schools is from staff-to-staff contact and when mask-wearing requirements are breached, Walensky said on NBC.

In recent weeks, the pace of vaccinations has picked up in the U.S., with about 11% of the population having received a first dose.

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