Covid-19 Live Updates: U.S. Airports See Rise in Travelers as Officials Warn of Deadly Consequences

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Dr. Anthony S. Fauci, the country’s top infectious disease specialist, and other health experts relayed a clear message on Sunday morning news shows: with coronavirus cases surging to record levels across the country, turning nearly every state into a hot zone of transmission, the risk of getting infected, whether in transit or in even small indoor gatherings, is high.

Up to 50 million people could be traveling on roads and through airports in the United States over Thanksgiving this year, according to AAA, the biggest travel surge since the pandemic began, despite strong cautions from the Centers for Disease Control and Prevention and other health authorities. A video of a packed airport in Phoenix has been circulating widely on social media. As of Sunday, 47 states — all but Vermont, Maine and Hawaii — were considered high-risk zones for viral transmission, and nationwide hospitalizations were at a record 83,227.

I’m an ER doctor in Arizona and our hospitals are being overwhelmed with COVID19. 7.4 million people & only 174 ICU beds left with healthcare workers calling out sick. Our pleas for help have fallen on selfish deaf ears – this is Phoenix airport @dougduceypic.twitter.com/7iLbngxHNp

— Cleavon MD (@Cleavon_MD) November 21, 2020

“Please seriously consider decisions that you make,” Dr. Fauci said on the CBS show “Face the Nation.” Encountering large numbers of people in airports and on planes is particularly dangerous, he said. Although airlines have invested in air circulation and ventilation systems to minimize viral transmission, Dr. Fauci said, “sometimes when you get a crowded plane, or you’re in a crowded airport, you’re lining up, not everybody’s wearing masks — that puts yourself at risk.”

And gathering indoors, whether you travel or not, carries risk. “When you’re eating and drinking, obviously, you have to take your mask off,” Dr. Fauci said. “We know now that those are the kinds of situations that are leading to outbreaks.”

Dr. Tom Inglesby, director of the Center for Health Security of the Johns Hopkins Bloomberg School of Public Health, said on Fox News Sunday that because about half of infections are spread by people who don’t have any symptoms, “you can’t assume that you don’t have the virus, and you can’t assume that the people whose home you’re about to enter don’t have the virus, at this point in our pandemic.”

He recommended celebrating Thanksgiving only with the people you live with. People who choose to visit others’ homes should spend as much time as possible outdoors and “should be wearing masks indoors when they’re together, and only removing them when they’re eating.”

Dr. Fauci and others warned that Americans’ behavior over Thanksgiving will have critical implications for the coming weeks of the winter season, including risks to people gathering to celebrate Christmas and New Year’s, because the country is still months away from having wide access to vaccines and therapeutics and the cold weather drives more people indoors.

“We’re going to have to, you know, hunker down, reduce our interactions,” Dr. Scott Gottlieb, a former Trump administration Food and Drug Administration commissioner, said on Face the Nation.

As an example of the risk, he said that in a state like North Dakota, where case levels are high, there’s a 50 percent chance that someone in a group of 10 people has Covid-19. “That’s the kind of risk we’re facing individually right now,” he said. “And that’s only going to get worse.”

The Food and Drug Administration has granted emergency authorization for the experimental antibody treatment given to President Trump shortly after he tested positive for the coronavirus, giving doctors another option to treat patients as cases across the country continue to rise.

The treatment, made by the biotech company Regeneron, is a cocktail of two powerful antibodies that have shown promise in early studies at keeping the infection in check, reducing medical visits for patients who get the drug early in the course of their disease. A similar treatment, made by Eli Lilly, was given emergency approval earlier this month.

The emergency authorization for Regeneron’s drug is limited in scope: It is for people who have tested positive for the coronavirus and who are at high risk for developing severe Covid-19. And evidence so far suggests that Regeneron’s antibody treatment, like Eli Lilly’s, works best early in the course of the disease, before the virus has gained a foothold in the body. Like Eli Lilly’s treatment, Regeneron’s is not authorized for use in people who are hospitalized or who need oxygen.

The emergency authorization raises immediate questions about who will get access to the treatments. An average of more than 168,000 coronavirus cases are reported each day in the United States, and hospitals are running out of beds in some regions of the country. Regeneron has said it will have enough of the drug for only about 80,000 people by the end of November, enough for 200,000 patients by the first week of January, and 300,000 by the end of January. After that, the company said it would be able to ramp up production thanks to a partnership with the Swiss manufacturer Roche.

Regeneron has received more than $500 million from the federal government to develop and manufacture the treatments. Although the first 300,000 doses will be provided for free, patients may be charged for having the treatment administered; it must be infused in a clinic or a hospital.

Antibody treatments have gotten less attention than vaccines, but health officials have long held out hope that they may serve as a possible bridge until a coronavirus vaccine is more broadly available. Two vaccines, one made by Pfizer and another by Moderna, were recently shown to be more than 90 percent effective in early analyses. Pfizer, which has completed its trial, submitted an application on Friday for emergency authorization of the vaccine, and Moderna said it also planned to apply soon. Still, it will take weeks for the F.D.A. to consider the applications, and if it issues approvals, access will be limited to people in high-risk groups.

Dr. George D. Yancopoulos, Regeneron’s president and chief scientific officer, said in a statement that he was encouraged by the recent vaccine results, but “there remains a need to treat patients who develop Covid-19, especially as some may not have had access to or were not protected by vaccination.”

Regeneron enjoyed a burst of publicity in October, when Mr. Trump received an infusion of its cocktail and then enthusiastically promoted the drug as something that had lent him a superpower-like feeling. In a video released on Oct. 7, the president claimed without evidence that it had cured him, and that he had authorized it — something he does not have the power to do.

It remains impossible to know whether the Regeneron treatment helped Mr. Trump. He was given multiple drugs while at Walter Reed National Military Medical Center, and many people recover from the virus on their own.

This month, two very different companies — the pharmaceutical giant Pfizer and the biotech upstart Moderna — reported spectacular results from high-stakes clinical trials of their experimental coronavirus vaccines. It was a remarkable feat: developing a vaccine that appears safe and effective in a matter of months, rather than the years or decades that such developments usually take.

A team of Times reporters — Sharon LaFraniere, Katie Thomas, Noah Weiland, David Gelles, Sheryl Gay Stolberg and Denise Grady — tracked how the extraordinary race unfolded, with so much at stake and such a complex backdrop. At play were not just commercial rivalries and scientific challenges but an ambitious plan to put the federal government’s Operation Warp Speed — and an often toxic political atmosphere created by President Trump — in the middle of the effort.

Pfizer’s chief executive, Dr. Albert Bourla, had vowed to avoid the political minefield but was forced to maneuver through it nonetheless. After promising a timetable that seemed to support Mr. Trump’s prediction of a breakthrough before Election Day, Dr. Bourla pushed back the schedule in late October, fearing his firm’s clinical trial results would otherwise not be convincing enough for federal regulators to grant emergency approval of its vaccine.

Dr. Bourla had chosen from the start to keep Pfizer and its research partner, the German firm BioNTech, at arms length from the government, declining research and development money from Operation Warp Speed.

But Pfizer’s main rival, Moderna, made the opposite bet, embracing the assistance of a government led by a science-denying president. Moderna got nearly $2.5 billion to develop, manufacture and sell its vaccine to the federal government and teamed up with the National Institutes of Health on the scientific work, a highly successful partnership that managed to sidestep the political meddling by Mr. Trump and his aides that had bedeviled other efforts to confront the virus.

Both companies were aided by a confluence of three factors. A new method of developing vaccines was already waiting to be tested, with the coronavirus a perfect target. Sky-high infection rates accelerated the pace of clinical trials, the most time-consuming part of the process. And the government was willing to spend whatever it took, eliminating financial risks and bureaucratic roadblocks and allowing mass production to begin even before the trials were done.

Their apparent success showed that in an era of polarized politics, science was able to break down barriers between government, countries and industry to produce one of the few pieces of good news in a year of suffering and division.

With coronavirus cases rising in every other state, Hawaii stands alone with a gradual decline in new cases in November.

Hawaii is averaging 80 cases per day on its collection of islands, a decrease of about a quarter from two weeks earlier. Hospitalizations have fallen by a similar amount.

So how has Hawaii managed to keep its caseload in check?

“Being surrounded by ocean has helped,” said Brooks Baehr, a spokesman for the Hawaii State Department of Health. “Hawaii has more control over interstate and international travel than other states.”

The recent decline in Hawaii cases has come amid an influx of several thousand more daily visitors since the authorities removed a 14-day quarantine requirement for travel to the state in mid-October. Rather than quarantining, everyone entering Hawaii must now obtain a negative test result from a verified lab in the 72 hours before arriving.

The restrictions have helped slow the travel-related rates of the coronavirus — most cases are from community spread — but they have come at a steep cost. Hawaii’s tourism industry, which accounts for 21 percent of the state’s total economy, has all but come to a standstill. In the first nine months of 2020, visitor arrivals were down 71.6 percent compared with the same period a year ago.

For residents, this meant many businesses closed and jobs lost. In the particularly fraught seven-week period between late March and early May, new unemployment claims averaged more than 30,000 per week; the same period in 2019 had a weekly average of around 1,200.

With cases exploding across the mainland and in other parts of the world, Hawaii is once again bolstering its protections.

Starting Tuesday, if an inbound air traveler’s negative test result is not available before boarding — even if that is because of a laboratory delay, as has often been the case lately — a quarantine becomes mandatory.

Also last week, Gov. David Ige issued the first statewide mask mandate, which requires everyone over age 5 to wear a face covering in public or risk penalties that include a $5,000 fine or up to a year in jail.

Senator Kelly Loeffler of Georgia, a Republican who is campaigning in a high-stakes runoff election that could determine control of the Senate, is isolating after receiving both a negative and positive test for the coronavirus on Friday and then receiving an inconclusive result on Saturday, a campaign spokesman said.

Ms. Loeffler has worn masks while interacting with people, but was indoors and unmasked among unmasked crowds at an event on Thursday. She wore a mask while greeting voters who lined up to meet her.

On Friday morning, she took two coronavirus tests, according to her campaign spokesman, Stephen Lawson.

One of those was a rapid test, which came back negative, and Ms. Loeffler “was cleared to attend” events on Friday, including a rally with Vice President Mike Pence and Senator David Perdue of Georgia, Mr. Lawson said. But the second test, a polymerase chain reaction, or P.C.R., test — which is considered more accurate — came back with a positive result after her events on Friday evening, he said.

Ms. Loeffler, 49, received another P.C.R. test on Saturday morning. But it was “inconclusive,” Mr. Lawson said of the results, which came in Saturday evening.

The senator followed C.D.C. guidelines by notifying those with whom she had had sustained contact while she awaits further test results, he said.

“She has no symptoms and she will continue to follow C.D.C. guidelines by quarantining until retesting is conclusive and an update will be provided at that time,” Mr. Lawson said in a statement.

Ms. Loeffler has held recent events with prominent Republicans, including Mr. Pence, Senator Tom Cotton of Arkansas and Mr. Perdue, who is also engaged in a runoff election that could determine control of the Senate. Mr. Perdue is remaining at home until more details are known about the health status of Ms. Loeffler.

“Senator Perdue will remain at home until Senator Loeffler receives confirmation of her test results,” wrote John Burke, a Perdue campaign spokesman, in a text message Sunday.

The Loeffler campaign did not provide an update on her status Sunday morning. Mr. Perdue, 70, has encouraged people to wear masks to help stop the spread of the coronavirus. But he has also appeared at rallies where people did not wear masks. A Friday tweet from Ms. Loeffler includes a picture that shows the two senators in an indoor setting without masks.

A spokesman for Mr. Pence, Devin O’Malley, said that “as he awaits a confirmatory test from Senator Loeffler, Vice President Pence is in regular consultation with the White House Medical Unit and will be following C.D.C. guidelines as he has in other circumstances when he has been a close contact.”

The last time Mr. Pence was deemed a close contact was last month, when his chief of staff, Marc Short, tested positive.

Mr. Pence continued to campaign then, with the White House saying that he was performing “essential” duties that exempted him from Centers for Disease Control and Prevention guidelines calling for people to quarantine for 14 days after exposure to the virus.

Ms. Loeffler, a businesswoman who is the Senate’s richest member, was temporarily appointed to her Senate seat late last year. She faces the Rev. Dr. Raphael G. Warnock, a Democrat, in an election on Jan. 5, when Georgia voters will also decide between Mr. Perdue and his opponent, Jon Ossoff, a Democrat.

A 3 percent positive rate in coronavirus testing is a critical threshold for New York City. It is the point at which the mayor shut down public schools last week. The governor says that a sustained 3 percent level in the city will result in banning indoor dining, closing gyms and hair salons, and placing a 25-person cap on attendance at houses of worship even as the holidays approach.

But as important as that 3 percent rate is, it seems the city and the state can’t agree on whether it has been reached.