Jay Bhattacharya, an unofficial Covid adviser in Trump’s first administration, has been chosen director of the National Institutes of Health (NIH), one of the world’s leading biomedical research institutions.

The election of Bhattacharya, a Stanford economist whose proposal for widespread Covid-19 infection was backed by the White House, would mark a return to controversial and scientifically questionable health policies in the second Trump administration, experts say.

Bhattacharya, an economist who studied medicine, called for a “complete transformation of the scientific community.”

He has questioned the safety of vaccines, testified against the effectiveness of face masks and argued that NIH officials should not be involved in scientific policy.

Bhattacharya did not respond to requests for comment.

In early 2020, Bhattacharya downplayed the lethality of Covid and soon joined two other scientists in a recommendation to allow Covid to spread with “targeted protection” – a proposal on the scientific fringe that soon became politically mainstream.

After the Trump administration adopted the strategy of “herd immunity” through infection, millions of Americans were disabled and killed, with mortality rates far higher than in other countries.

In April 2020, Santiago Sanchez, then a first-year student at Stanford Medical School, wanted to do something to help as the novel coronavirus swept the country and brought the world to a standstill.

So he volunteered in a makeshift laboratory in the ballroom of the Palo Alto Sheraton, carefully pressing blood samples into rapid tests for ten to twelve hours a day.

The research project was an attempt to find out how many people had already had Covid. If more people were already sick and recovered than previously known, that would mean that the virus was not as serious as it seemed, and it could also mean that there are enough people with immunity to stop the virus from spreading. Sanchez hoped.

But as he saw one negative result after another, Sanchez felt his optimism slip. After two days, volunteers had conducted more than 3,300 tests, but fewer than two dozen were positive, Sanchez recalls.

That’s why he was puzzled when one of the study’s lead researchers, Jay Bhattacharya, walked into the ballroom, saw the handful of positive tests next to stacks of negative tests and said, “There’s definitely a signal here,” according to Sanchez’s recollection.

“That was my first bad feeling because I thought, ‘That’s not how I interpret this experiment,'” Sanchez said.

The subsequent preprint study estimated that between 2.5 and 4 percent of people in the region were infected – a rate far higher than previously thought and a number significantly higher than the number of positive tests, which Sanchez said he saw.

Bhattacharya became a fixture on Fox News and other networks, proclaiming the opposite of what Sanchez now believed: that many more people were infected with the virus than anyone thought, and that meant the U.S. should reopen.

“He was everywhere during the pandemic except hospitals,” said Jonathan Howard, associate professor of neurology and psychiatry at NYU Langone Health and author of the book We Want Them Infected. “He didn’t treat a single Covid patient himself and became famous even though he had no real responsibility in the world in that way.”

Scientists quickly discovered significant errors in the study: The people who donated blood were not a random sample; the positive tests may well have been false positives; and the study was sponsored in part by an airline founder who was an enthusiastic supporter of reopening in the midst of the worst of the coronavirus crisis.

Despite the criticism, the study results “got out of control,” Sanchez said. “I and many others who worked on this study shared a feeling of being exploited, as if we were pawns in an obviously ideological project that did not meet scientific requirements.”

A few months later, Bhattacharya and other skeptics of Covid precautions met with President Trump at the White House, at a time when Trump had stopped speaking to his chief medical adviser Anthony Fauci.

Bhattacharya and two other scientists, Sunetra Gupta and Martin Kulldorff, soon unveiled a plan called the Great Barrington Declaration, which would allow the virus to spread uncontrollably through the population while attempting to protect the vulnerable. The authors believed this approach could stop the pandemic within three to six months.

“This is not mainstream science. It’s dangerous,” said Francis Collins, then director of the NIH.

But the day after the proposal was released, the authors met with Alex Azar, then Secretary of Health and Human Services, who confirmed that the proposal reflected the Trump administration’s reopening policies.

Within a few months, the worst wave of deaths of the entire pandemic hit the United States. The strategy of protecting the weak was never realized; Even Trump, perhaps the most protected person in the country, was hospitalized with Covid.

“He was an anti-infection advocate,” Howard said of Bhattacharya. “He said that parts of the country had reached herd immunity in the summer of 2020… He said that infection had led to durable, robust immunity, and he viewed rare side effects of the vaccine as a fate worse than death.”

Over the past four years, Bhattacharya has testified in state and Canadian courts as well as in U.S. Congressional hearings. Bhattacharya said that public health had become a “tool of authoritarian power… a political instrument used to enforce the biosecurity state” and that the field needed to be rebuilt.

When Sanchez sees patients who say they don’t need a Covid booster shot, he wonders whether they have been directly or indirectly influenced by Bhattacharya’s messages.

And he sees a direct connection between the economist’s Covid advice and his possible employment at the NIH.

“They gave Trump a huge gift. “They gave him an opportunity to talk about the pandemic, which obviously reached many people, which allowed them to isolate what was happening in their own minds and to feel that it was OK to tolerate the level of disability and death.” Sanchez told the researchers.

“It has completely undermined people’s ability to even assess the risk, to the point where we have well-established, highly effective vaccines for children that are now being rejected – to the point that measles is widespread in some parts of the United States come back.”

With confidence in public health having plummeted, the impact could be long-lasting and tragic in the years ahead, especially as Trump’s health appointees undermine confidence in the safety and effectiveness of vaccines and other public health precautions, Howard said.

“Any outbreak of measles, any outbreak of whooping cough will weigh on them.”