Marc Ernstoff, a physician who has pioneered immunotherapy research and treatments for cancer patients, said his work as a federal scientist proved untenable under the Trump administration.
Philip Stewart, a Rocky Mountain Laboratories researcher focused on tick-borne diseases, said he retired two years earlier than planned because of hurdles that made it too challenging to do his job well.
Alexa Romberg, an addiction prevention scientist focused on tobacco, said she 鈥渓ost a great deal鈥 of the research she oversaw when federal grants vanished.
鈥淚f one is thinking about the 鈥楳ake America Healthy Again鈥 agenda and the prevention of chronic disease,鈥 Romberg said, 鈥渢obacco use is the No. 1 contributor to early morbidity and mortality that we can prevent.鈥
The National Institutes of Health is the largest public funder of biomedical research in the world, with a to "enhance health, lengthen life, and reduce illness.鈥
Over decades, the value of the NIH may be the one thing everyone in Washington has agreed on. Lawmakers have routinely boosted its funding.
鈥淚鈥檓 so pleased to be associated with NIH,鈥 former Sen. Roy Blunt, a Missouri Republican and one of the NIH鈥檚 biggest champions in Congress, shortly before he retired.
But in President Donald Trump鈥檚 second term, the NIH has seen an exodus of scientists like Ernstoff, Stewart, and Romberg. Federal data shows the NIH lost about 4,400 people 鈥 more than 20% of its workforce. Scientists say the departures harm the U.S.鈥 ability to respond to disease outbreaks, develop treatments for chronic illnesses, and confront the nation鈥檚 most pressing public health problems.
鈥淧eople are going to get hurt,鈥 said Sylvia Chou, a scientist who worked at the National Cancer Institute in Rockville, Maryland, for over 15 years before she left in January. 鈥淭here鈥檚 going to be a lot more health challenges and even deaths, because we need science in order to help people get healthy.鈥
Why They鈥檙e Leaving
麻豆女优 Health News interviewed a half dozen scientists who said they quit their jobs years before they鈥檇 planned to because of the tumult of 2025.
Only a few years ago, the NIH workforce was steadily growing, from roughly 17,700 employees in fiscal year 2019 to around 21,100 in fiscal 2024, federal data shows. Under Trump, those gains have been slashed.
The Trump administration enacted a campaign to purge government workers perceived as disloyal to the president. People were fired or encouraged to leave. Officials instituted a months-long freeze on hiring.
The NIH workforce has plummeted to about 17,100 people 鈥 its lowest level in at least two decades. Most who left weren鈥檛 fired. Roughly 4 in 5 either retired, quit, had appointments that expired, or transferred to a different job, according to federal data.
Scientists watched with dread as their colleagues were forced to terminate research funds for topics the Trump administration deemed off-limits. Across NIH labs, routine work stalled. They said they faced major delays in accessing equipment and supplies. Travel authorizations were slowed or denied.
Agency staff were instructed not to communicate with anyone outside the agency. When they could talk again, they were subject to greater constraints on what they could present to the public.
And under the administration鈥檚 agenda to eliminate 鈥渄iversity, equity, and inclusion,鈥 references to minorities or health equity were purged from NIH-funded research. Initiatives to protect Americans鈥 health were gutted. Among them: support for early-career scientists, ways to prevent harm from HIV or substance use, and efforts to study how different populations鈥 immune systems respond to disease.
, Chou and Romberg were among a group of NIH scientists who said they resigned in protest of an administration 鈥渢hat treats science not as a process for building knowledge, but as a means to advance its political agenda.鈥

A 鈥楩undamental Destruction鈥
Health and Human Services spokesperson Emily Hilliard said in a statement that the agency had shifted to focus on evidence-based research over 鈥渋deological agendas.鈥 She said the NIH is still recruiting 鈥渢he best and brightest鈥 and advancing high-quality science to 鈥渄eliver breakthroughs for the American people.鈥 The federal health department oversees NIH.
鈥淎 major reset was overdue. HHS has taken action to streamline operations, reduce redundancies, and return to pre-pandemic employment levels,鈥 Hilliard said.
Many scientists, however, question whether the NIH can still fulfill its public mission.
鈥淭here鈥檚 been a fundamental destruction,鈥 said Daniel Dulebohn, a researcher who spent nearly two decades at Rocky Mountain Laboratories in Hamilton, Montana. It鈥檚 going to 鈥渢ake a very, very long time to rebuild.鈥
Dulebohn left the NIH鈥檚 infectious disease and allergy institute in September.
He analyzed how molecules and proteins interact in diseases, such as Lyme disease, HIV, and Alzheimer's 鈥 information that鈥檚 key for new treatments. Dulebohn was a resource for scientists when they hit walls trying to understand, for example, if molecules could prevent infection or react to a treatment.
Now he and his wife are living off savings in Mexico with their three young kids. Dulebohn鈥檚 thinking about what鈥檚 next. One option: real estate.
The expert in biochemical analysis operated equipment few others know how to use. His exit further depletes resources in the specialty.
鈥淚t's clear when someone comes out with a drug and now you've just cured a disease. But you never know which ones could have been cured,鈥 Dulebohn said. 鈥淲e don't know what we've lost.鈥
Laura Stark, a Vanderbilt University associate professor who specializes in the history of medicine and science, said wiping out NIH staff will propel a shift toward private-industry research, with its profit motives, 鈥渁s opposed to actually helping American health.鈥
鈥淲e just don鈥檛 have people who are now able to pursue research for the public good,鈥 Stark said.
From Support to Scrutiny
Stark said the seeds of the present-day NIH were planted during World War II when the U.S. government spearheaded an effort to mass-produce the antibiotic penicillin to save soldiers from infections.
The agency has played a central role in lifesaving discoveries and treatments 鈥 including for heart disease, cancer, diabetes, and genetic diseases such as cystic fibrosis.
With bipartisan backing from Congress, the NIH budget has grown significantly over time, sitting at $48.7 billion for fiscal 2026. The NIH allocates roughly 11% of its budget for agency scientists. About 80% is awarded to universities and other institutions.
The money may be there, but the people who get it out the door are not, scientists said.
Jennifer Troyer left the National Human Genome Research Institute in Bethesda, Maryland, on Dec. 31, after working in various positions at the NIH for about 25 years. The division she led reviews research and oversees grants to organizations studying the human genome 鈥 or a person鈥檚 complete set of genes 鈥 and how it can be used to benefit health.
Last year, she said, her division lost about two-thirds of its staff. 鈥淭here really are not enough people there right now to actually get the work done,鈥 Troyer said. 鈥淚t鈥檚 extreme harm.鈥
She decided to quit the day Trump issued an in August that prohibited the use of grants to 鈥渇und, promote, encourage, subsidize, or facilitate鈥 what it described as 鈥渁nti-American values.鈥 It also allowed political appointees to review all funding decisions.
鈥淚 wasn鈥檛 going to operate a division under those orders,鈥 Troyer said. She hasn鈥檛 figured out her next career steps.

鈥楨nough Is Enough鈥
Research aligned with the administration鈥檚 stated priorities has suffered.
HHS Secretary Robert F. Kennedy Jr. has called the diagnosis and treatment of Lyme disease 鈥 a tick-borne infection that can cause debilitating lifelong symptoms 鈥 . In December, Kennedy said the government had long dismissed patients burdened with a disease that in the U.S. are diagnosed with annually.
That same month, Stewart, who had dedicated his career to ticks and Lyme disease as a federal scientist, retired early. He'd worked for the government for 27 years. Stewart said workforce cuts and travel delays stalled his efforts to confirm how far Lyme-carrying ticks had spread 鈥 information that could help doctors recognize symptoms sooner.

Stewart was a lead scientist on research published last year , or deer tick, in Montana. It was the first time the tick best known for transmitting Lyme disease had been confirmed in the state. He wanted to determine if the discovery was a fluke or an indicator that the species was gaining ground.
鈥淭he advice we've been getting is, 鈥楶ut your head down below the trench line. Don't look. Don't peek over and risk getting shot,鈥欌 Stewart said. 鈥淎t what point do you finally say, 鈥楨nough is enough鈥 and 鈥榃e're not being effective anymore鈥?"
Scientists said those early in their careers are looking abroad for jobs and training. People who want to stay in the U.S. are running into problems getting hired because of cuts to research grants and uncertainty about funding.
Collectively, people studying diseases warn the U.S. could lose its long-held position as the global leader in biomedical research, with devastating impact.
Stanley Perlman, a University of Iowa virologist who studies pediatric infectious diseases, said that title earned the nation more than prestige; it drew top scientists from the world over to the U.S. to study diseases that particularly affect people here.
There's no guarantee halted research will be picked up elsewhere, whether by private industry or other countries. If others are doing that work, Americans could face delays in seeing benefits, he said.
鈥淚f you don鈥檛 have access to how the work was done,鈥 Perlman said, 鈥渋t鈥檚 harder to reproduce and adapt it for your country.鈥
麻豆女优 Health News data editor Holly K. Hacker contributed to this report.
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