WASHINGTON (REUTERS) - After a Thanksgiving weekend when the number of people travelling through US airports reached its highest since mid-March, a top government official said on Monday (Nov 30) some Americans could begin receiving coronavirus vaccinations before Christmas.

US Health Secretary Alex Azar said Pfizer's Covid-19 vaccine could be authorised and shipped within days of a Dec 10 meeting of outside advisers to the Food and Drug Administration tasked with reviewing trial data and recommending whether it warrants approval.

A vaccine from Moderna could follow a week later, he said, after the company announced on Monday it would apply for US and European emergency authorisation. Final trial data showed the vaccine to be 94.1% effective at preventing Covid-19, comparable with Pfizer's results.

"So we could be seeing both of these vaccines out and getting into people's arms before Christmas," Azar said on CBS' This Morning. The federal government will ship the vaccines. State governors will decide how they are distributed within their states.

The United States has reported 4.2 million new Covid-19 cases so far in November and more than 36,000 coronavirus-related deaths, according to a Reuters tally.

Hospitalisations are at a pandemic high and deaths the most in six months.

Thanksgiving surge

As the virus rages across the country, overwhelming hospital systems and pushing already exhausted medical staff near a breaking point, US officials pleaded with Americans to avoid holiday travel and limit social gatherings.

Many appear to have disregarded those pleas over the long Thanksgiving weekend as the Transportation Security Administration screened 1.18 million airline passengers on Sunday, the highest since mid-March.

That number is still about 60% lower than the comparable day last year when 2.88 million passengers were screened, the highest ever recorded by the agency.

"There almost certainly is going to be an uptick (of infections) because of what has happened with the travel," Dr Anthony Fauci, one of the nation's top infectious diseases experts, told ABC's This Week on Sunday.

More than 93,000 Americans are currently sick enough with Covid-19 to require hospitalisation. Experts worry that number will keep rising as the weather gets colder and people gather indoors more often. Increases in hospitalisations tend to lag spikes in new cases by a few weeks.

"Hospital capacity is the top concern," New York Governor Andrew Cuomo told reporters on Monday. He ordered all elective surgeries to cease in one county and urged hospitals state-wide to again ready their plans to increase capacity by 50% if necessary or set up and staff field hospitals.

With the latest wave of the virus spiking across the country and no federal blueprint to combat it, 25 states have issued new or revamped restrictions on businesses, schools and social life in an attempt to curb the spread.

In New Jersey, Governor Phil Murphy said he was re-tightening the limit on outdoor gatherings to 25 people, effective Dec 7, with exceptions for funerals, memorials and weddings. Religious and political activities such as protests are also exempt.

Murphy, who has brought back a series of Covid-19 restrictions in recent weeks, also said all indoor youth and adult sports will be put on hold from Dec 5 through Jan 2, 2021, also with exemptions.

"As you start to make your holiday plans, please recognize that the gathering limits are back to what they were in May and June - when we all came together and crushed the curve as much as any state in the nation," he wrote on Twitter. "Keep gatherings as small as possible."

But in New York City, Mayor Bill de Blasio reversed course on Sunday, announcing that public schools would start to reopen for in-class instruction five days a week for students who want to attend full time. Previously, students were offered a mix of online and in-person instruction.

Health officials found the rate of people testing positive in public schools to be significantly lower than in the city and state. "The schools are some of the safest places to be right now in New York City," de Blasio told CNN.