The U.S. case rate is dropping, down by 63.4% since the peak three weeks ago, according to federal data.

For the first time since December, U.S. daily cases are below 300,000. 

However, experts continue to caution that the U.S. isn't out of the woods. Case levels remain much higher than the nation's previous surges and the U.S. is still reporting millions of new cases every week. Experts also point out that many Americans taking at-home tests are not submitting their results, and thus, case totals may be higher than reported.

On average, about 13,000 Americans with COVID-19 are being admitted to the hospital each day -- a 26.4% drop in the last week, according to federal data.

Emergency department visits with diagnosed COVID-19 cases are also on the decline, down by nearly 60% in the last month, federal data show.

The U.S. death average is at a plateau, with the nation reporting around 2,300 new COVID-19-related deaths each day, according to federal data. That average is significantly lower than last winter when the nation peaked around 3,400 deaths per day.

-ABC News' Arielle Mitropoulos

The presence of the omicron sub-variant, BA.2, is increasing in the U.S., according to new data published by the CDC.

BA.2 was estimated to accounted for 3.6% of new COVID-19 cases in the U.S. as of Feb. 5. BA.2 was projected to account for 1.2% of new cases the week prior.

The original omicron strain, B.1.1.529, still makes up the vast majority of new cases, accounting for an estimated 96.4% of cases in the U.S.

There is still much unknown about the BA.2 variant, but currently it doesn't appear to demonstrate a more severe illness. There's also no indication to suggest that BA.2 will further impact the efficacy of vaccines.

The delta variant, which accounted for 99.2% of all new cases just two months ago, is now estimated to account for 0% of new cases.

-ABC News' Arielle Mitropoulos, Eric M. Strauss

An ongoing, trucker-led protest against COVID-19 vaccine mandates and other pandemic-related restrictions in Canada spilled over into the United States via the Ambassador Bridge on Monday night, blocking access to one of the world's largest international suspension bridges.

The protesters hindered traffic at the tolled bridge across the Detroit River, which connects Windsor, Canada, with Detroit, Michigan, at the Canadian-U.S. border. The Michigan Department of Transportation (MDOT) announced via Twitter on Monday night that it had closed the crossing to Canada.

The Windsor Police Service tweeted Tuesday morning that the bridge has reopened to U.S.-bound traffic. Meanwhile, MDOT tweeted an update saying the crossing remains closed on the U.S. side.

Monday marked the 11th straight day of the so-called "Freedom Convoy" protests, which began with truckers critical of a new rule that they must be vaccinated against COVID-19 to cross the Canada-U.S. border. The demonstrations have since grown into broader challenges to pandemic-related public health measures and opposition to Canadian Prime Minister Justin Trudeau.

Thousands of protesters have occupied the streets of Ottawa and other cities across Canada in support of the movement, paralyzing the capital's city center with traffic jams, nonstop noise and alleged harassment. Protesters have said they won't leave until all COVID-19 vaccine mandates and restrictions are lifted nationwide. They are also calling for the removal of Trudeau's government, even though most of the public health measures were put in place by provincial governments.

The House of Commons of Canada held an emergency session on Tuesday to discuss the demonstrations. In an opening statement, the prime minister said he understands "people are tired" of COVID-19 but that protests are not the answer.

"These pandemic restrictions are not forever," Trudeau told lawmakers.

While Trudeau's opponents argued that the country is at a crisis point, the prime minister rejected any notion that Canadians are divided.

"Canada has one of the highest vaccination rates of our peer countries around the world," he said. "It's because Canadians trust science. Canadians trust each other to do the right thing."

Oregon will lift general mask requirements for indoor public places no later than March 31, state health officials announced Monday.

According to the Oregon Health Authority, scientists expect that about 400 or fewer people would be hospitalized with COVID-19 statewide by late March, which is the level of hospitalizations Oregon experience before the highly contagious omicron variant began to spread. Mask mandates for Oregon schools will be lifted on March 31 to give school districts time to prepare.

However, the Oregon Health Authority said the state needs to keep mask requirements in place for now as COVID-19 hospitalizations crest and the health care system struggles to treat high numbers of severely ill patients.

The Oregon Health Authority has filed a new rule with the Oregon Secretary of State to require people to wear masks while indoors in public places. The new rule replaces a temporary one that expired Monday.

State health officials will consider lifting the general indoor mask requirement earlier than March 31 if hospitalizations decline to the levels projected by the end of March sooner than expected. Once the mandates are lifted, employers and businesses may continue to establish their own mask requirements to protect employees and customers, according to the Oregon Health Authority.

Pfizer said it has postponed its application to the FDA to expand the use of its COVID-19 vaccine for kids under 5.

Pfizer instead will continue with its study on the three-dose vaccine and seek authorization when that data is available.

"We believe additional information regarding the ongoing evaluation of a third dose should be considered as part of our decision-making for potential authorization," Pfizer said.

Dr. Peter Marks, the FDA’s vaccine chief, told reporters Friday, “We realized now, in data that came in very rapidly because of the large number of cases of omicron, that at this time, it makes sense for us to wait until we have the data from the evaluation of a third dose before taking action."

Marks acknowledged that the change was “late breaking” -- the FDA’s committee of independent advisers was scheduled to review and vote on authorizing the vaccine next week -- but said the job of the FDA was to “adjust” to new data amid an unpredictable virus.

“The data that we saw made us realize that we needed to see data from a third dose as in the ongoing trial in order to make the term determination that we could proceed with doing an authorization,” Marks said.

Pfizer has predicted it will be able to submit data on the third dose in early April.

-ABC News' Eric M. Strauss, Cheyenne Haslett