Newly elected US President Donald Trump has picked leading Covid lockdown skeptic Jay Bhattacharya as the next director of a key US public health agency.

Trump said he selected the Stanford University-educated physician and economist to lead the National Institutes of Health (NIH), the world’s largest government-funded biomedical research institute.

During the pandemic, Bhattacharya became the face of a hotly contested open letter – known as the Great Barrington Declaration – opposing widespread lockdowns.

Tuesday’s nomination rounds out Trump’s top public health team. He has already unveiled all 15 posts for his Cabinet as he prepares to take office on January 20.

Earlier this month, Trump announced that he would nominate former rival Robert Kennedy Jr. the US Department of Health wanted to lead. Kennedy’s vaccine skepticism has alarmed the medical community, although his calls for stricter regulation of food ingredients have drawn praise.

In a statement, Trump said Bhattacharya would work with Kennedy to “restore the NIH to a gold standard for medical research as they investigate the root causes of and solutions to America’s greatest health challenges, including our crisis of chronic diseases and conditions.”

On Tuesday, the president-elect also nominated Jim O’Neill — a former federal health official and close ally of conservative donor Peter Thiel — as deputy secretary of the Department of Health.

But it is Bhattacharya who is more widely known after questioning the public health response to the Covid outbreak four years ago.

In October 2020, Bhattacharya co-authored an open letter known as the Great Barrington Declaration, calling for an alternative to lockdowns, recommending the focus instead be on protecting vulnerable groups such as the elderly.

He remains an outspoken critic of the way Anthony Fauci – a former director of the US National Institute of Allergy and Infectious Diseases, a division of the NIH – handled the pandemic.

Then-NIH Director Francis Collins said at the time that the Great Barrington Declaration, which came before Covid vaccines were available, was dangerous and dismissed its authors as “fringe experts.”

Bhattacharya is not the only Trump nominee who has criticized US public health authorities’ response to the pandemic.

Trump has also picked Marty Makary, a Johns Hopkins surgeon who opposed the Covid-19 vaccine mandate, to lead the Food and Drug Administration (FDA).

Dave Weldon, a physician and former Republican congressman who has also raised doubts about the safety of vaccines, was picked to lead the Centers for Disease Control and Prevention (CDC).

Kennedy and O’Neill’s Department of Health would oversee all of Makary, Weldon and Bhattacharya’s agencies, but all must be confirmed by the Senate.

Last week, Trump also nominated TV personality Dr. Mehmet Oz as administrator of the Centers for Medicare and Medicaid Services.

While Trump’s choices for U.S. public health agencies have generally been welcomed by his allies, not all have been welcomed by conservatives.

He has also nominated Dr. Janette Nesheiwat, a Fox News medical contributor, to become the next surgeon general.

Her past comments against abortion restrictions and in support of masking schoolchildren during the pandemic have upset some Trump supporters.