Director of National Institutes of Health (NIH) Dr Francis Collins holds up a model of SARS-CoV-2, known as the novel coronavirus, during a U.S. Senate Appropriations Subcommittee hearing on the plan to research, manufacture and distribute a coronavirus vaccine, known as Operation Warp Speed on Capitol Hill in Washington, D.C, U.S., July 2, 2020. Saul Loeb/Pool via REUTERS