Watch live: Fauci and health officials update Senate on returning to work and school amid COVID

Top health officials including Dr. Anthony Fauci, one of the nation’s top infectious diseases experts, are testifying Tuesday morning before the Senate to offer an update on progress that’s been made in moving the nation toward returning to work and school.

Fauci, the director of the National Institute for Allergy and Infectious Diseases, along with Admiral Brett Giroir, the assistant secretary for Health and Human Services; Dr. Stephen Hahn, the Food and Drug Administration commissioner; and Dr. Robert Redfield, director of the Centers for Disease Control, are appearing before lawmakers on the Senate Health, Education, Labor and Pensions (HELP) Committee. They’ll be testifying as COVID-19 cases have been increasing in some states. In Florida and Texas, governors have paused or rolled back some of their reopening measures.

Fauci warned Sunday that the U.S. is not likely to achieve herd immunity to the coronavirus if a portion of the population refuses to get a vaccine once it’s available. If enough people in a population are immune to a disease, generally through vaccination, this helps suppress outbreaks and provide protection to people who are not immune. 

Fauci said in an interview that was part of the Aspen Ideas Festival that he’d “settle” for a COVID-19 vaccine that is between 70% and 75% effective.  However, with that level of effectiveness, if 25% of Americans do not get vaccinated, Fauci said it’s “unlikely” the U.S. will reach herd immunity. According to Johns Hopkins Bloomberg School of Public Health, the percentage of needed for herd immunity ranges between 70% to 90%, depending on how contagious a disease is.

Fauci, a member of the White House coronavirus task force, has expressed concern and frustration lately about “a general anti-science, anti-authority, anti-vaccine feeling among some people in this country.”  

On testing, which is considered to play an important role in monitoring the progress of the disease among Americans as states reopen, Giroir told a House panel last week that the U.S. is conducting around 500,000 tests per day, with the expectation that 40 to 50 million tests will be conducted per month by the fall.