California recorded 30,851 new cases on Tuesday, bringing the state's case total to over 1.42 million.

The Golden State's seven-day positivity rate stands at 10%.

California Gov. Gavin Newsom has ordered regions to follow a stay-at-home order if their intensive care unit capacity falls below 15%.

The San Joaquin Valley and Southern California regions have already met this criteria and are under stay-at-home orders until at least Dec. 28.

The Greater Sacramento region now meets the criteria and a stay-at-home order will go into effect there the night of Dec. 10.

Northern California and the Bay Area are the two remaining regions with ICU capacities above 15%.

Once the FDA approves the Pfizer/BioNTech vaccine, 2.9 million doses will go out immediately in the U.S., said Gen. Gus Perna, commander of the Army Materiel Command. The second batch of 2.9 million will be close behind, within 21 days, Perna said.

Twenty million Americans are expected to be vaccinated by the end of 2020, Health and Human Services Secretary Alex Azar said.

"We remain confident that across our portfolio of multiple vaccines, we will have enough doses for any American who wants a vaccine by the end of the second quarter of 2021," Azar said.

After two allergic reactions to the Pfizer/BioNTechvaccine were reported in the United Kingdom, Moncef Slaoui, Trump’s chief scientific adviser on vaccines, told reporters, "The expectation would be that subjects with known severe reaction, allergic reaction, should not take the vaccine, until we understand exactly what happened here."

ABC News' Anne Flaherty contributed to this report.

The last week marks the deadliest week for the U.S. since the beginning of the pandemic, with 15,578 deaths -- roughly equivalent to 92 deaths reported every hour.

The U.S. is now averaging more than 200,000 new cases each day -- three times higher than the country's summer peak in July, and more than six times higher than the country's spring peak in April.

There has not been a single day with less than 100,000 daily cases for the last five straight weeks, according to an ABC News analysis of data compiled by the COVID Tracking Project.

In the last week alone, the U.S. has reported 1.4 million new COVID-19 cases, more than any other week on record, and equivalent to 1 in every 231 Americans testing positive.

With numerous days now over the 200,000 mark, the seven-day average of new coronavirus cases has increased by 87% in the last month.

ABC News' Arielle Mitropoulos contributed to this report.

Pennsylvania Gov. Tom Wolf said he tested positive for COVID-19 on Tuesday and is isolating at home.

"I have no symptoms and am feeling well," Wolf said in a statement. “I am continuing to serve the commonwealth and performing all of my duties remotely."

Wolf's wife has been tested and is awaiting results.

U.S. Surgeon General Jerome Adams urged people to take the coronavirus pandemic seriously and follow public health guidelines as infections and hospitalizations soar across the country.

"I want the American people to know this virus is incredibly unforgiving, cases are going up, hospitalizations are going up, my colleagues are dog-tired and we need you to hang on just a little bit longer because we've got vaccines coming but we want as many people to be alive to get them as possible and a lot of that is going to depend on your behavior," Adams told ABC News chief anchor George Stephanopoulos in an interview Monday on "Good Morning America."

Although "more people than ever are wearing masks," Adams said he's "very" concerned by the number of people who still "don't understand how much spread is occurring by people who don't have symptoms."

About 20 million "full doses" of COVID-19 vaccines will be available by the end of the year, according to Adams, who urged every American to be immunized against the virus as soon as a vaccine is authorized and made available.

"It's a way that we can ultimately end this pandemic, but it doesn't matter if people won't get the vaccination," the surgeon general said. "We know that vaccine levels are only about 50% for adults for flu and they go down to about 40% for African-Americans."

Adams said he is working with historically black colleges and universities as well as faith communities to bolster vaccine confidence among all populations. The White House is also hosting a vaccine summit Tuesday, he said.

"One thing you can all do right now, it's national flu immunization week, get your flu shot because half a million people were hospitalized last year with the flu," Adams said. "We simply can't afford for that to happen this year with hospitals being overwhelmed."

The surgeon general said the current surge in infections across the country "is different than earlier surges," because it's not about a lack of masks or personal protective equipment, nor is it due to a lack of testing.

"It's really about health care capacity, and certain places are just being overwhelmed," he said. "So we know that we can actually help them with their health care capacity by immunizing their health care staff. We're going to leave it up to the states, but we're going to give them guidance."

Adams noted it's also important to vaccinate those who are most likely to die from COVID-19.

"We know that 40 to 50% of the deaths are occurring in people who are in longterm care facilities who are older," he said.