Members of the White House coronavirus task force are split on whether California's stay-at-home orders are backed up by science

• White House coronavirus task force officials publicly disagreed on Monday over California's new stay-at-home orders.
• Top infectious disease expert Dr. Anthony Fauci told CNN that the state didn't have "any choice" but to impose the restrictions.
• Yet coronavirus testing czar Adm. Brett Giroir raised concerns on Fox News about "overly restrictive" measures that are "not supported by the science."
• California Gov. Gavin Newsom announced the latest orders on Sunday, shutting down non-essential businesses and impacting roughly 27 million people in the state due to increased COVID-19 hospitalizations.

White House coronavirus task force officials are divided over California's latest stay-at-home orders, which affect roughly 27 million people in the state.

Dr. Anthony Fauci, the US's top infectious disease expert. came out in support of the restrictions on Monday and said they "absolutely" make sense to him.

"I have been in discussion with the health authorities from the state of California, who called me and asked, you know, they said: 'We feel we need to do this. What do you think?'" Fauci said in a CNN interview. "And I said, you know, you really don't have any choice. When you have the challenge to the health care system, you've got to do something like that."

However, the Trump administration's COVID-19 testing czar, Adm. Brett Giroir, raised concerns about "overly restrictive" measures that are "not supported by the science" in a Monday interview on Fox News.

California Gov. Gavin Newsom announced new shutdown rules on Sunday, forcing businesses such as bars, salons, and movie theaters to close alongside other personal service providers and recreation centers. The order also bans gatherings with people from outside of one's household and enforces mask-wearing whenever in public.

"The health authorities in places who are making those decisions, they're there on the ground, they know what's best for their local situation," Fauci told CNN. "So I'd be backing them based on what I know is good experience that they have."

Giroir disagreed, telling Fox News, "we need to do what's necessary to turn the pandemic, but not more that's not evidence-based - that's going to be counterproductive."

The mandate impacts residents of Southern California, including Los Angeles and San Diego, as well as much of Central Valley where intensive care unit capacities have fallen below the 15%. In the Bay Area, San Francisco Mayor London Breed announced that the county will also follow the measures as they are "on pace to run out of hospital beds."

Giroir took aim at some of the specific rules imposed by Newsom's administration, saying he has not seen evidence "that says you need to shutdown outdoor dining or outdoor bars," which could potentially cause "a lot more harm."

"It's time to nuance," Giroir told Fox News. "This is not March or April. This is December. We know what the science says, we know there are countermeasures that are effective."

As of Monday, California the worst-hit state in the US with more than 1.3 million COVID-19 cases, per Johns Hopkins University. It has experienced an 84% uptick in confirmed new infections over the past two weeks, according to data compiled by The New York Times.

Another White House coronavirus task force member, Dr. Deborah Birx, warned on Sunday that the pandemic could trigger the worst chapter in US history this winter.

"This is not just the worst public health event," Birx said on NBC's "Meet the Press." "This is the worst event that this country will face, not just from a public health side."