Scientists are also uneasy about Trump’s choice to lead the NIH, Dr. Jay Bhattacharya, a Stanford University health economist who criticized COVID lockdowns in the first months of the pandemic. Reports suggest he wants to tie future NIH awards to the perceived degree of academic freedom on the university campuses where many recipients work.

The financial stakes for Massachusetts alone are considerable, with researchers in the past fiscal year receiving more than $3.3 billion from the NIH — the third largest amount behind California and New York. Across New England, NIH’s support totaled more than $4.6 billion.

The funding supports more than 5,000 projects in Massachusetts,including the hunt fornewmedicines to slow the threat of antibiotic-resistant infections, repurposing existing drugs to treat Alzheimer’s,and improving the safety of organ transplants for older people as the population rapidly ages.

But many concerned researchers are choosing their words carefully, saying they feel caught in the political crosshairs, amid considerable uncertainty. Several declined to speak on the record.

Dr. Nahid Bhadelia, founding director of Boston University’s Center on Emerging Infectious Diseases, said she is concerned by Kennedy’s statements that he would shift priorities from infectious disease research, which she said would leave the United States less prepared to contain outbreaks.

Bhadelia and other researchers also noted that scientists have increasingly linked viral infections to chronic diseases such as long COVID and multiple sclerosis,which is associated with the Epstein-Barr virus,illustrating the need to robustly fund research on both.

Dr. Elias Zerhouni, NIH director under President George W. Bush, said in a briefing Friday that NIH historically had strong bipartisan support in Congress and was largely spared cuts and outside interference during Trump’s first administration because the agency’s director at the time, Dr. Francis Collins,had good relationships within Congress.

But Zerhouni said he is now deeply concerned about NIH’s future because of the mistrust in science spawned during the COVID-19 pandemic.

“It’s lost its sort of apolitical status of being above politics, and it’s lost some of its bipartisan support,” Zerhouni said. “I think it’s going to be rocky.”

Ultimately, Congress restored Trump’s proposed 2017 NIH budget cuts, and funding in Massachusetts and New England spiked during the pandemic. Still, veteran researchers say this time feels more precarious.

“There is a lot more anxiety here and more [people] sitting on the edge about what is going to happen,” said Sameer Sonkusale, a Tufts University professor of biological, chemical, and electrical engineering.

Sonkusale and colleagues recently received $3 million from NIH to develop wearable sensors to monitor and measure chronic pain, a notoriously challenging diagnosis for physicians and patients.

Now Sonkusale is worried the new administration may claw back that two-year award as well as funding for the program it came from, the Advanced Research Projects Agency for Health because theinitiative was started by President Biden. Known as ARPA-H, it is designed to speed biomedical and health solutions.

Trump’s transition team did not respond to a request for comment.

“It’s technology-driven and ambitious and targeted,” Sonkusale said. “Finally, [the government] had the vision to do something big, and I hope they don’t go back on some of the excellent ideas.”

But some scientists say there are reasons for guarded optimism.

Bhattacharya, Trump’s NIH director appointee, is himself a researcher who has received millions of dollars in roughly 40 NIH grants since 2001. Some scientists hope that will make Bhattacharya sympathetic to their situation andinsulate the sprawling agency from deep cuts.

Several also pointed to Trump’s Operation Warp Speed, the public-private partnership that rapidly developed the COVID-19 vaccine in less than a year, a remarkable feat given most vaccine development takes five to 10 years.

“The Trump administration prioritized it,” said Lizbet Boroughs, associate vice president for government relations and public policy at the Association of American Universities, which represents leading research universities.

But illustrating the confusion and lingering doubts about Trump and science since COVID-19, Boroughs added: “The incoming president does not seem to be taking a whole lot of credit for his early investment and early push to get that highly effective vaccine that was able to get kids back to school, that was able to protect older people in nursing homes.”

And others hope that Trump’s vow to reduce wasteful federal spending through a new Department of Government Efficiency may actually end up benefitting them by cutting down on onerous requirements.

Ellie Dehoney, senior vice president of policy and advocacy at the nonpartisan alliance, Research!America, noted that 40 percent of researchers’ time is spent on paperwork for grants.

“I think this new administration wants government efficiency,” Dehoney said. “So what can we do to reduce that burden? This is an opportunity, too. Sometimes we are losing sight of that.”

Several researchers saidthey plan to call attention to the value of their work by drumming up grass-roots support.

“People are well aware that the space race to put someone on the Moon resulted in Velcro and microwaves and other things we use in our everyday lives,” said Jennifer Nuzzo, director of the Pandemic Center at Brown University School of Public Health. “Similarly, HIV research resulted in discoveries of our immune system and our understanding of the human body. It has allowed people to better understand how the immune system works, to develop anti-viral medicines and vaccines generally. There are spill-over benefits.”

And, Bhadelia said her center at Boston University, which analyzes patterns and predicts threats from infectious diseases, intends to step up its public outreach.

“Maybe we hold more sessions, invite people to come in and ask questions, have more webinars … and engage the community to build back the trust in science,” she said.

At Harvard Medical School, pioneering geneticist George Church has received roughly three dozen grants from the NIH over the past 20 years and witnessed peaks and valleys in federal funding.He takes reassurance from how, over time, private industry has ended up augmenting or advancing research underwritten by the government, such as when NIH-funded genome technologies were replaced by significantly cheaper commercial innovations.

“When you squish something, it kind of goes in a new crevice,” he said. “You block one crevice, it goes in another. So I think that’s probably what will happen.

“I really believe,” Church added, “that science keeps marching forward no matter what, and the politicians just take credit for it.”

Neena Hagen of the Globe staff contributed to this story.

Kay Lazar can be reached at kay.lazar@globe.com Follow her @GlobeKayLazar.