Anthony Fauci to face grilling from Senate Republicans on Covid pandemic | US Senate

Anthony Fauci, the former veteran director of the National Institute of Allergy and Infectious Diseases (Niaid) who served as a key adviser to Donald Trump and Joe Biden on the Covid-19 pandemic, is due to testify on Wednesday at a high-profile US Senate hearing.

Senators are expected to question Fauci about whether the Covid-19 virus began as a “lab leak”, a claim virologists have argued is unlikely. The testimony is part of a longtime Republican investigation into the origins of the pandemic, led by Senator Rand Paul of Kentucky.

While Republicans have characterized their work as investigating “the origins of Covid-19 and risky taxpayer-funded life science research”, scientists have characterized Paul’s investigation as “vilification and harassment” of Fauci, who led Niaid for 38 years before retiring in 2022.

“For years, Americans were told a lab origin wasn’t just unlikely – it was dismissed outright by the very people funding and reviewing this research,” Paul, who chairs the Senate committee on homeland security and governmental affairs, where Fauci is scheduled to testify, said last week.

Fauci, who is 85, served under seven US presidents and through numerous health crises, including the HIV crisis, Ebola outbreaks and the first coronavirus outbreak, called Sars-CoV-1. He became a household name overnight when the Covid-19 pandemic halted social life in 2020.

The “lab leak” theory has since gained significant traction in Republican circles. In just one example, the White House published a treatise on the theory in April 2025 that served as a rationale for defunding the National Institutes of Health (NIH).

A 2024 survey of virologists from the Global Catastrophic Risk Institute found that most believed the pandemic began as a so-called spillover event, or a virus jumping from an infected animal to a human. Similarly, a group of virologists argued in the Journal of Virology that the “preponderance” of evidence points to a spillover, even as the “lab leak” theory received outsized attention.

The scheduled hearing comes just days after Paul released what he described as Fauci’s “diary”, a more than 1,100-page document characterized as revealing Fauci’s inner conflicts about the lab leak theory. Scientists have said this is a normal part of reaching scientific opinion.

The diary also contained entries about Trump, who he advised closely during the early days of the pandemic. He described the president as “rambling”, “crazy”, “desperate”, “bumbling”, “incompetent”, “an idiot”, “a true embarrassment”, “totally nuts” and “truly an obnoxious adolescent”.