CDC Issues Increasingly Assertive Advice as Coronavirus Pandemic Surges

“While their role has been diminished during this current crisis, they play a very important role in all this,” she said. The new administration will rebuild public health and data infrastructure, restore C.D.C. staffing in its overseas outposts and give “control back to the C.D.C.”

Within the C.D.C., there is a palpable sense of relief and a determination to return to an apolitical identity, according to four senior scientists who spoke on condition of anonymity because they feared for their jobs.

“We couldn’t allow ourselves to be politicized at this moment in time,” said one of the scientists, who is involved in the agency’s pandemic response. “We weren’t going to spend time licking wounds and worrying about what had gone wrong in the past.”

Another senior C.D.C. scientist said, “Sometimes you just feel compelled to say, ‘I don’t care what happens, I’ve got to do this.’”

Until the pandemic, the C.D.C. was widely regarded as the world’s leading public health agency. But the muzzling of its scientists by the Trump administration and the politicization of some of its advice crippled its efforts to answer critical questions, experts say, including how schools, churches and businesses should reopen, and how Americans could best protect themselves and their families.

The turnabout began after the Trump administration meddled in the C.D.C.’s vaunted weekly bulletins, the Morbidity and Mortality Weekly Reports, according to Dr. Thomas R. Frieden, who led the agency under President Barack Obama.

Political appointees tried to revise, delay or even halt publication of the reports, sparking public outcry and condemnation at a congressional hearing. The dust-up precipitated the swift exit of Michael Caputo, a political appointee who had accused C.D.C. scientists of sedition, and Dr. Paul Alexander, a science adviser hired to help Mr. Caputo.