President Trump has selected Susan Monarez, the acting director of the Centers for Disease Control and Prevention, to lead the agency permanently.
The president withdrew his first nominee, Dr. Dave Weldon, just hours before his confirmation hearing. If confirmed by the Senate, Dr. Monarez, an infectious-disease researcher, will be the first nonphysician to lead the agency in more than 50 years.
“Americans have lost confidence in the C.D.C. due to political bias and disastrous mismanagement,” the president wrote on Truth Social, adding that Dr. Monarez would work with the health secretary, Robert F. Kennedy Jr., to address the chronic disease epidemic and restore the agency’s accountability.
“As an incredible mother and dedicated public servant, Dr. Monarez understands the importance of protecting our children, our communities, and our future,” Mr. Trump wrote.
Dr. Monarez, 50, assumed the acting director position a few days after Mr. Trump took office in January, leaving her perch as deputy director of a new federal biomedical research agency created during the Biden administration.
Dr. Monarez was expected to serve until Mr. Trump’s first choice for the job, Dr. Weldon, could be confirmed. But after Mr. Trump decided to withdraw the nomination, Republican aides in the Senate said that Dr. Weldon had failed to impress them with a plan for the agency.
Dr. Weldon blamed two Republican senators — Susan Collins of Maine and Bill Cassidy of Louisiana — for turning against him.
Some experts said Dr. Monarez marked a sharp contrast to Dr. Weldon, whose skeptical views on childhood vaccines aligned with those of Mr. Kennedy and raised alarm in the medical community.
Mr. Kennedy’s response to a growing measles outbreak in Texas and New Mexico, including his lukewarm recommendation of vaccination, has drawn considerable criticism. Dr. Monarez is a biosecurity expert who endorsed the Covid vaccines, and her selection may signal a growing impatience with anti-vaccine sentiment.
“She has a strong reputation as a solid researcher and expert in infectious diseases,” said Dr. Georges Benjamin, executive director of the American Public Health Association.
“She clearly understands public health and the role governmental public health plays,” he said. “I believe the public health community can work with her in a positive manner.”
But Dr. Monarez has spent weeks away from Atlanta, where the agency is headquartered. She has not attended the agency’s all-hands meetings or offered reassurance to employees unsettled by the tumult of the past weeks, according to several C.D.C. employees who spoke on condition of anonymity for fear of retaliation.
A comment section on the agency’s internal website was quickly deleted after staff members began to note that they wanted more communication from her.
Center directors have been interpreting the president’s executive orders and various court instructions with little input from the director, the officials said.
Instead, the acting director’s office has served as a conduit for directives from the White House and the Department of Health and Human Services.
For example, she has been working with the cost-cutting initiative known as the Department of Government Efficiency to plan reductions to the agency, according to a former official with knowledge of the matter.
And when the Trump administration ordered the C.D.C. to take down pages from its website containing phrases like “L.G.B.T.Q.” and “transgender,” Dr. Monarez did not resist nor attempt to preserve important data, according to three people with knowledge of the events, who spoke on condition of anonymity for fear of retaliation.
