The daily case average in the U.S. has dropped to its lowest point since Christmas, with the nation now reporting an average of 215,000 new cases each day -- a 71% drop in the last three weeks, according to federal data.

However, even with the declines, nearly 99% of U.S. counties are reporting high transmission. Also, many Americans are taking at-home tests and not submitting their results, so case totals may be higher than reported.

U.S. hospitalization rates are also declining.

On average, about 12,100 Americans are being admitted to the hospital with COVID-19 each day, down by about 25% in the last week, according to federal data.

The national average continues to plateau around 2,300 new COVID-19-related deaths per day.

-ABC News' Arielle Mitropoulos

About 3,000 municipal workers in New York City -- less than 1% of the city's workforce —- face termination Friday after refusing to abide by a COVID-19 vaccine mandate.

The requirement, established under former New York City Mayor Bill de Blasio, applies to municipal employees hired after Aug. 2, 2021, who were told to be vaccinated against COVID-19 as a condition of employment and to unvaccinated police officers, correction officers, firefighters and others who opted to forego city health benefits and are currently on leave because they are not vaccinated.

The mandate achieved a vaccination rate among municipal workers of more than 95%. A number of exceptions were approved in recent months.

New York City Mayor Eric Adams said Thursday that some workers initially facing termination had submitted their proof of vaccination, so the final number wasn't yet clear. He reiterated that the stragglers aren't being fired but are "quitting."

"The responsibility is clear," Adams told reporters Thursday. "We said it. If you were hired, you get this job, you have to be vaccinated. If you are not following the rules, you are making that decision. You are making the decision that you are not going to follow the rules of getting vaccinated. And that is a decision they are making."

"I want them to stay, I want them to be employees of the city," he added. "But they have to follow the rules."

-ABC News' Mark Crudele and Aaron Katersky

The first vaccine shipments for children under 5 could arrive at pediatricians' doors as soon as Feb. 21, according to a planning guide sent to states from federal health officials and obtained by ABC News.

Doses can ship once the FDA signs off.

The FDA's independent advisory committee will meet on Tuesday and after that the FDA can issue an emergency use authorization.

The CDC's independent advisory panel is expected to meet within days of the FDA's authorization. Once the CDC signs off on its panel's recommendations, vaccinations for kids under 5 can start.

-ABC News' Sasha Pezenik

CDC Director Rochelle Walensky acknowledged that it's tough to make national guidelines to ease restrictions that will fit every different city and town.

"One of the challenging pieces has been how we make guidance that is general enough so that it can be applied to New York City and rural Montana and Indian country, which is our responsibility, and yet have it be specific enough so that people can get their questions answered," Walensky said in a webinar in hosted by the COVID-19 Vaccine Education and Equity Project.

Looking to the future, Dr. Peter Marks, the FDA's vaccine chief, said "Obviously the hope is -- and I think it's probably the 90% scenario -- is that we're going to now move into a period where ... the virus becomes endemic. And we will be living alongside it probably in a period where we will start to get yearly boosters for it."

But Dr. Sara Oliver, an epidemic intelligence service officer for the CDC, noted that, although there's a drop in cases, the same hasn't happened yet in hospitals.

"It's difficult to envision a time point where we can say COVID is over if we're still in a time period where our hospitals and ICUs are feeling the strain," Oliver said.

-ABC News' Cheyenne Haslett

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