“When you add those cuts up,” he added, they “will inevitably impact health security.”
Republicans in Congress are no less critical.
“Sometime in the president’s term, you will have a pandemic,” Representative Tom Cole, Republican of Oklahoma, told the president’s budget director, Mick Mulvaney, at a House budget hearing on Wednesday. “You will have a Zika, you will have an Ebola,” Mr. Cole said.
“Cutting the Centers for Disease Control, I think, leaves you very vulnerable and the American people very vulnerable,” he said.
Over all, the C.D.C.’s budget would be cut 17 percent. Dr. Thomas R. Frieden, who recently retired as the director of the C.D.C. and led its 2014 Ebola response, sent more than a dozen bullet points on Twitter last week cataloging how the proposed budget was “Unsafe at Any Level Of Enactment.”
Trump administration officials say they are trying to refocus scientific research in an era of domestic austerity. Too much federal science is competing with work that could be done in the private sector, they say. Under the president’s budget, the National Institutes of Health at large would be cut 18 percent. Within that, the National Institute of Allergy and Infectious Diseases, which handles Zika, Ebola and H.I.V./AIDS vaccine research, would lose 18 percent of its budget.
“The administration wholeheartedly believes in the commitment to research,” Mr. Mulvaney said Wednesday at the House budget hearing. “We’d like to see more focus on what they call basic research, which is research further away from the marketability of products because that is one of the gaps that the government can and should fill.”
The targeting is remarkably specific. At the N.I.H., the Fogarty International Center, a small program that in part trains foreign leaders in pandemic response, would be eliminated. Thousands of scientists and global health professionals rallied on Capitol Hill in April to protest the plan after a list of programs targeted for eradication was released.
“They’re making a very radical statement,” Dr. Morrison said. “The big picture is a movement toward suspicion of international programs. The administration is threatening to abandon multilateralism in a big way.”
Global health programs at the State Department and the United States Agency for International Development would be cut by at least a quarter.
”Our operations must become more efficient, and our assistance must become more effective,” Hari Sastry, the director of the State Department’s Office of U.S. Foreign Assistance Resources, told reporters on Tuesday. “Our primary mission is going to remain advocating for the national interests of our country.”
Military and border patrol spending will increase, if Mr. Trump’s request is funded. But scientists warn that a $1.6 billion project to begin constructing a southern border wall will not keep out the most lethal outbreak of bird flu in history, which recently killed 40 percent of patients in China, nor will it keep out Ebola, which has resurfaced in the Democratic Republic of Congo, with 37 suspected cases this month.
“The next weapon of mass destruction may not be a bomb,” said Lawrence O. Gostin, the director of the World Health Organization’s Collaborating Center on Public Health Law and Human Rights. “It may be a tiny pathogen that you can’t see, smell or taste, and by the time we discover it, it’ll be too late,” Mr. Gostin said.
“The closed-border, highly nationalistic, America-first vision is not the world’s scientific view of how to keep a population safe and healthy,” he said.
The president’s requests on biomedical research and defense are likely to be greeted skeptically by Congress, which ultimately controls spending levels. Lawmakers in both parties have greatly increased funding for the N.I.H. budget, and Georgia’s two senators, both Republicans, have protected the C.D.C. and its Atlanta headquarters.
Senator John McCain, Republican of Arizona, called the Trump proposal “dead on arrival.” And in the House budget hearing on Wednesday, Mr. Cole pressed Mr. Mulvaney on proposed cuts to the disease surveillance program.