Hewing to a startlingly ambitious timetable for rollout of the first coronavirus vaccine, Dr. Moncef Slaoui, the chief science adviser of Operation Warp Speed, said on Sunday that residents of long-term care facilities, who in some states account for about 40 percent of deaths from the coronavirus, will receive the first round of vaccinations by mid-January, perhaps even by the end of December.
The timing assumes that the Food and Drug Administration authorizes the vaccine, made by Pfizer, this week or shortly thereafter. An advisory committee to the agency will meet on Thursday to review the data on safety and efficacy.
If the agency authorizes the vaccine, distribution could begin as soon as the end of this week, Dr. Slaoui added. “By end of the month of January, we should already see quite a significant decrease in mortality in the elderly population,” he said on CNN’s “State of the Union.”
Barring unexpected problems with manufacturing the vaccine, most Americans at high risk from coronavirus infection should be vaccinated by mid-March, and the rest of the population by May or June, he added.
President-elect Joseph R. Biden Jr. sounded a considerably more skeptical note on Friday, saying that there was “no detailed plan that we’ve seen, anyway, as to how you get the vaccine out of a container, into an injection syringe, into somebody’s arm.”
Dr. Slaoui said his team expected to meet Mr. Biden’s advisers this week and brief them on details of the plan for the vaccines’ distribution.
Britain has already approved the Pfizer vaccine and expects to begin immunizing its population this week. Like the F.D.A., European regulators are still examining data on the vaccine’s safety and effectiveness.
A second vaccine, made by Moderna, also has been submitted to the F.D.A. for emergency authorization.
Dr. Slaoui was optimistic about long-term protection from the vaccine. The elderly or people with compromised immune systems might need a booster in three to five years, he said, but for most people the vaccine should remain effective for “many, many years.”
Still, it’s unclear whether those who have been immunized may still spread the virus to others. “The answer to that very important question” should be known by mid-February, he said.
Up to 15 percent of those receiving the shots experience “significant, not overwhelming” pain at the injection site, which usually disappears in a day or two, Dr. Slaoui told CBS’s “Face the Nation,” also on Sunday.
Vaccines have not yet been tested in children under 12, but Dr. Slaoui said that clinical trials in adolescents and toddlers might produce results by next fall.
Operation Warp Speed was expected to have 100 million doses of the Pfizer vaccine by December, a number that has since been slashed by more than half.
Although the clinical trials were completed faster than expected because of the high level of virus transmission in the United States, manufacturing problems scaled down the expected number of available doses to 40 million.
Dr. Slaoui warned of possible further delays. “This is not an engineering problem. These are biological problems, they’re extremely complex,” he said. “There will be small glitches.”
Much of California will be under stay-at-home orders as of late Sunday night — with outdoor dining and bars shuttered, schools closed and playgrounds roped off — as the state tries to control an accelerating coronavirus surge and head off a catastrophic shortage of intensive care beds.
Under orders issued Thursday by Gov. Gavin Newsom, regions are to be placed under the new restrictions once their intensive care unit availability falls below 15 percent. The governor has warned that without drastic action, hospitals will soon be overwhelmed.
On Saturday, two regions hit the I.C.U. threshold and learned that at 11:59 p.m. Sunday they would have to begin complying with the stay-at-home orders for at least three weeks: Southern California was at 12.5 percent, and the San Joaquin Valley at 8.6 percent. Together, the regions are home to more than half of California’s population of 40 million.
In the San Francisco Bay Area, local officials announced Friday that the region would adopt the new limits before hitting the threshold.
California’s new measures are its strictest since the beginning of the pandemic, when it became the first state to issue a stay-at-home order. That order helped the state gain control of an early outbreak, but daily case reports have tripled in the last month. More than 25,000 new cases were reported statewide on Saturday, the fourth straight single-day record. Los Angeles County, with more than 8,900 new cases, broke its record for the third straight day.
Nationally, the news is also grim. On Friday, more than 229,000 cases were reported and the seven-day rolling average of new cases passed 183,700, both records. More than 101,000 Americans are in hospitals now, double the number from just a month ago.
Delaware, Michigan, Oregon, Washington State and cities from Philadelphia to Los Angeles have reimposed restrictions.
Much of California was already under a curfew prohibiting nearly all residents from leaving their homes to do nonessential work or to gather from 10 p.m. to 5 a.m.
The new order includes prohibitions on private gatherings and requires retail businesses to operate at a limited capacity. Any open businesses must require everyone inside to wear masks and distance themselves. Among the facilities that must close: hair salons and barbershops; museums, zoos, and aquariums; indoor movie theaters; wineries and breweries.
“We are at a point where surging cases and hospitalizations are not letting up,” Dr. Salvador Sandoval, a public health officer for the San Joaquin Valley city of Merced, told The Associated Press. “I can’t emphasize this enough — everyone must take personal steps to protect themselves and protect others.”
Many people are weary after nine months of shifting rules about where they can go, whether they can eat indoors or outdoors and whether their children can go to school. Questions remain about the level of compliance with the new restrictions and about how strictly they will be enforced.
Sheriff Don Barnes of Orange County said in a statement on Saturday that his deputies would not enforce them because compliance with health restrictions was “a matter of personal responsibility and not a matter of law enforcement.”
Mr. Newsom has emphasized that California will withhold funding from counties that refuse to enforce the new stay-at-home order. After some counties pushed back on prevention measures during a summer surge, the governor appointed an enforcement task force that through November has levied more than $2 million in fines against businesses, issued 179 citations and revoked three business licenses.
For residents, such as David White, a senior pastor at Porterville Church of God in the San Joaquin Valley city of Porterville, these new restrictions are a blow to residents who have taken the virus seriously from the start.
“We look back and think we’ve given up so much for so long, and in hindsight it was nothing,” he said. “Statistically, nothing compared to now.”
Of all the toxic dumps in New Jersey, perhaps none was more infamous than PJP Landfill, which sat at the edge of the Hackensack River in Jersey City and was polluted by hazardous chemicals. For more than a decade there, underground fires erupted spontaneously, belching acrid smoke so thick it could snarl traffic on an adjacent bridge, the Pulaski Skyway, a key link for commuters heading to and from New York City.
Now the site, which was designated a Superfund priority by the Environmental Protection Agency in 1983, is being converted into a public park with one of the nation’s first memorials to victims of Covid-19.
As part of a $10 million makeover, more than 500 trees will be planted in a grove of the newly named Skyway Park — one for every Jersey City resident who has died of the coronavirus, the mayor, Steven M. Fulop, announced on Thursday.
Each person’s name will also be included on a memorial wall, giving relatives of the dead a place to mourn. Many families were unable to observe traditional funeral rituals as the pandemic ravaged the Northeast.
“We wanted to do something significant for those families that didn’t get to grieve properly, and we’re taking a step forward in that direction,” Mr. Fulop said. “It has been a tough year for the city.”
For Mr. Fulop, the pain is personal. His grandmother died of Covid-19, and the City Council lost one of its members, Michael Yun, to the virus in April.
The site of the former industrial landfill has been remediated and capped to make it safe for visitors, but extra soil will be brought in for planting.
Vernon Richardson, who was an aide to Mr. Yun, said the park would “represent the resiliency of the city — everyone from those who died to those who loved them to those who just had a bad 2020.”
Before this year, Wesley Yang had never celebrated with a real Christmas tree. Growing up, his family deemed it an inconvenience. But stuck at home this season, Mr. Yang and his roommate decided to do something different to mark the end of a tragic year, spending $90 on a tree and lugging it up three floors to their Los Angeles apartment.
“We’re just trying to keep the spirit going, even though we are locked down these days,” he said.
As many people stay home for the holiday season, planning smaller celebrations as they seek some joy during the coronavirus pandemic, Americans like Mr. Yang seem to be driving up demand for Christmas trees.
Families are trying to make the most of whatever experiences remain safe this holiday season, like going outside to pick out a tree together and decorating it, said Jennifer Greene, the executive director of the North Carolina Christmas Tree Association, which represents a state that harvests more than 4.1 million trees a year.
“We didn’t realize that the Christmas spirit was going to help people with what we’ve heard called the ‘Covid blues,’” said Doug Hundley, a spokesman for the National Christmas Tree Association.
National sales data is hard to find, but across the country Christmas tree grower associations say that retailers are running through their tree supplies quickly and that growers are reporting a big increase in sales. In Michigan, farmers have seen as much as a 50 percent increase, said Amy Start, the executive director of the Michigan Christmas Tree Association.
George Nash travels each year from Vermont to New York City to sell more than 15,000 trees at spots across Upper Manhattan. “The demand is crazy right now,” he said. “We are almost twice ahead of where we were last year at this point, in terms of sales. If the trend holds, it will be the best year we ever had.”
Even artificial tree companies like Balsam Hill say they are having a banner year. Mac Harman, the company’s founder and chief executive, said its Christmas in July sale had foreshadowed this year’s voracious holiday market.
“It just absolutely has not slowed down,” he said.
A survey conducted over the summer of more than 2,000 adults by TRUE Global Intelligence found that more than half of the respondents said the pandemic had strengthened their desire to spend money on experiences rather than gifts this year. Three-quarters of the respondents considered real Christmas trees to be an experience, rather than a product.
With such a high demand for Christmas trees, some worry that it may be harder for some Americans to find trees later in the month. The industry is still reeling from the 2008 economic recession, when customers bought fewer items. Growers then cut down fewer trees, which left less space for seedlings that would have made the market more abundant about a decade later.
“We’re having difficulty filling extra orders from the States,” said Shirley Brennan, the executive director of the Canadian Christmas Tree Growers Association, whose office has fielded daily calls from south of the border. “That demand, we can’t keep up with.”
That doesn’t mean that Americans who waited to get a tree will end up without one, said Marsha Gray, the executive director of the Christmas Tree Promotion Board, a tree research and promotion program funded by growers.
“Some locations might close early, some locations may not have trees to sell,” she said. “But over all, there are enough trees and there aren’t communities going without.”
After a tough fall semester battling the varied ramifications of the coronavirus pandemic, many university officials are preparing to do something a lot of experts considered unthinkable a few months ago: bring even more students back onto campus in January and February. They say lessons learned from the fall will allow them to offer a more traditional college experience in the next semester.
The University of California, San Diego, is making room for more than 11,000 students in campus housing — about 1,000 more than it housed in the fall. The University of Florida is planning to offer more face-to-face classes than it did before the pandemic. And Princeton University, which let only a few hundred students live on campus last semester, has offered space to thousands of undergraduates.
“What makes me optimistic is we had the virus in our community, and each time we did, we were able to stop transmissions dead,” said David Greene, president of Colby College in Maine, which brought its whole student body back in the fall using aggressive health measures, and plans to do the same again next semester.
Many institutions are choosing not to bring back more students, planning instead to hunker down over the winter as infections mount and the nation awaits a vaccine. The University of Michigan, which spent a rocky fall trying to keep thousands of students on campus, has told most of its students to stay home and study remotely next semester.
But the alternative has been particularly compelling for schools that managed the fall with relatively minimal infections, and the schools that watched and learned from them.
Students have proved more conscientious than the public may think, administrators say. The culture of fraternities, big sports and big parties remains a challenge, but at many schools, students themselves reported the majority of health violations.
Many university officials say they are also increasingly confident that the virus is not being transmitted in classrooms, where professors are enforcing mask wearing and social distancing rules.
“The spread is in teacher break rooms, in fraternities and sororities,” said Dr. Tom Frieden, who ran the Centers for Disease Control and Prevention during the Obama administration and is now president of a global health initiative to prevent heart disease and epidemics. “It’s not even in organized sports but in locker rooms before and pizza parties after.”
Facing global anger over their initial mishandling of the outbreak, the Chinese authorities are now trying to rewrite the narrative of the pandemic by pushing theories that the virus originated outside China.
In recent days, Chinese officials have said that packaged food from overseas might have initially brought the virus to China. Scientists have released a paper positing that the pandemic could have started in India. The state news media has published false stories misrepresenting foreign experts as having said the coronavirus came from elsewhere.
The campaign seems to reflect anxiety within the ruling Communist Party about the continuing damage to China’s international reputation brought by the pandemic. Western officials have criticized Beijing for trying to conceal the outbreak when it first erupted.
The party also appears eager to muddy the waters as the World Health Organization begins an investigation into the question of how the virus jumped from animals to humans, a critical inquiry that experts say is the best hope to avoid another pandemic. China, which has greatly expanded its influence in the W.H.O. in recent years, has tightly controlled the effort by designating Chinese scientists to lead key parts of the investigation.
By spreading theories that foreigners are responsible for the pandemic, the party is deploying a well-worn playbook. The Chinese government is rarely willing to publicly address its own shortcomings, often preferring to redirect attention elsewhere and rally the country against a common enemy.
China’s leader, Xi Jinping, has led a vigorous effort this year to play down his government’s early failures in the crisis, instead arguing that the party’s success in containing the virus shows the superiority of its authoritarian system.
While recent studies have indicated that the coronavirus may have infected people in the United States and elsewhere earlier than previously thought, researchers still believe the most likely explanation is that it started circulating in China.
Edward Holmes, a professor at the University of Sydney who has studied the coronavirus, said the idea that the virus originated outside China seemed to be gaining traction for political purposes. “It lacks scientific credibility and will only further fuel the conspiracy theories,” he said.
Chris Buckley contributed reporting. Albee Zhang contributed research.
About 190,000 students in New York City are set to return to classrooms this week, starting with elementary school students on Monday, following a monthslong roller coaster of changes to the most closely watched school reopening effort in the country. Students with complex disabilities will be able to return to school buildings on Wednesday.
Mayor Bill de Blasio became the first big-city mayor in the country to reopen public schools this fall. But he closed the system briefly last month after virus cases surged in the city, before announcing that classrooms would again open for about 20 percent of the overall school system. It is not yet clear when middle and high schools will reopen.
The vast majority of the city’s roughly 1.1 million students have chosen to learn from home indefinitely.
Classrooms are reopening amid an alarming increase in virus transmission in New York City: The city reported on Sunday that the average test positivity rate has exceeded 5 percent; it was below 3 percent just a few weeks ago.
Mr. de Blasio’s decision to reopen schools for young children is the most high-profile example of a national and international trend of welcoming elementary school students back into classrooms, while their older peers learn remotely. Public health experts and educators generally agree that in-person learning for young children is relatively safe and particularly crucial for their development.
The mayor has said he will try to keep the school system open even if virus cases continue to rise, though it is likely that many classrooms and schools will temporarily close in the coming weeks as positive cases are confirmed in individual schools.
Across the world, mass vaccination campaigns are beginning, or just about to.
Russia began its campaign on Saturday. Britain will start its campaign on Tuesday. The United States hopes to start large-scale vaccinations this month, as does Turkey. Hundreds of thousands of people have already been vaccinated in China, and thousands in the United Arab Emirates and elsewhere.
But the mass vaccination efforts differ in one profound way: Some rely on a vaccine that has completed human trials — and some do not.
The vaccines that have, like the Pfizer/BioNTech vaccine approved in Britain and expected to be approved shortly in the United States, have more evidence of efficacy and safety. Those that have not — the Russian and Chinese vaccines — carry uncertainties that vaccine experts say should be settled before being given to millions of healthy people.
For one thing, researchers want to be assured that if people get Covid-19, despite having been vaccinated, they develop a milder form of the disease rather than an enhanced one.
The race for a coronavirus vaccine has been a global undertaking from the start. When Chinese scientists shared the genome of the virus on Jan. 10, researchers around the world leapt to begin designing vaccines.
In March, the first clinical trials of coronavirus vaccines in humans were launched by Moderna in the United States and Sinovac in China. More vaccine makers joined the effort, including in India, Thailand and Cuba. Today there are 13 vaccines in final, Phase 3 human trials and a total of 58 vaccines being tested on people. Dozens more are in preclinical tests.
The vaccines vary in how they prompt the body’s immune response. Moderna and Pfizer use a relatively new technology, creating genetic molecules encased in oily bubbles. The Sputnik vaccine uses adenoviruses to shuttle in genes. China’s Sinovac and Sinopharm vaccines contain dead coronaviruses.
No one has ever created a licensed human vaccine for any coronavirus before, and the world has been eagerly waiting to see what works best and most safely. Vaccine skepticism exists in countries like the United States and Brazil anyway, and Covid vaccines are open to much more, given the speed of their development and the nationalistic rivalries involved.
As governments around the world jockeyed to place advance orders, without knowing which vaccine — if any — would turn out to work, global health experts began warning that vaccine nationalism would undermine the worldwide fight against a virus that respects no borders.
The United States used its Operation Warp Speed program to make purchases from six vaccine makers. Russia and China have promoted their vaccines to a number of developing countries, using them as a medical form of soft diplomacy.
Last month, the first results of Phase 3 clinical trials for four vaccines came to light, showing high efficacy rates for Sputnik V and the vaccines from Pfizer/BioNTech, Moderna and AstraZeneca. The news was heartening. But researchers are still waiting in most cases for something more than company news releases to dig their teeth into.
In some cases, the initial announcements have left them confused.
The announcement about the Sputnik V vaccine claimed an efficacy rate of 91.4 percent based on the first 39 cases of Covid-19 in the trial — a relatively small number to base such big conclusions on. But the announcement also claimed that an analysis of an unspecified number of volunteers three weeks after the second dose revealed an efficacy rate of 95 percent.
While China has five vaccines in Phase 3 clinical trials, there has been no announcement about whether any are safe and effective. That has not stopped the Chinese government from getting a nationwide vaccination program ready and planning to approve a staggering 600 million doses for sale by the end of the year.
The U.S. Food and Drug Administration is scrutinizing the raw data from the vaccine trials by Pfizer and BioNTech, and the companies will provide more detailed public documents in advance of a meeting on Thursday of a special F.D.A. panel of experts. The panel is expected to turn to the Moderna vaccine after that. Full scientific reports are expected to start appearing in medical journals shortly.
Even as coronavirus infections in the occupied West Bank soared over the past week, large numbers of Palestinians in the territory continued to flout social-distancing requirements.
Though the authorities late last month established nightly closures for weekdays and general lockdowns from Thursday night to Sunday morning, many Palestinians have continued to gather without wearing masks.
On Saturday, hundreds of people, few of them wearing face coverings, took part in the funeral of Ali Abu Aliya, a Palestinian teenager who was killed by Israeli gunfire on Friday during clashes involving stone throwing at Israeli security forces.
The Israeli Army said it would investigate the events. Nickolay Mladenov, a senior United Nations envoy, called the boy’s death “shocking” and “unacceptable,” and the European Union’s representative office in Jerusalem accused Israel of using excessive force.
At the funeral procession in al-Mughayir, a Palestinian village near Ramallah, participants crowded around Ali’s body as it was carried through the street.
On Wednesday, Mahmoud Abbas, the president of the Palestinian Authority, made a rare appeal to Palestinians to follow social-distancing guidelines and wear masks.
“I ask you to take care of yourselves,” Mr. Abbas said in a short televised speech. “At every moment, there’s a danger.”
Over the past seven days, Palestinian officials in the West Bank recorded an average of 1,319 positive virus tests daily — more than triple the amount from a month ago, according to the health ministry of the Palestinian Authority. As of Sunday, there were more than 13,800 active cases in the territory, ministry data showed.
Palestinian officials were expected to meet in the coming days to discuss the possibility of introducing new restrictions, officials said Saturday.
Health care workers began vaccinating thousands of people in Moscow against the coronavirus on Saturday, a campaign that will expand nationally next week despite relying on a vaccine that has not been fully proven to be safe and effective.
Doctors, health care workers, social workers and teachers — all judged to run the highest risk of exposure to the virus — are receiving the vaccine in 70 locations across the city, and are to receive a second 21 days later.
Russia drew widespread criticism when it registered its Sputnik V vaccine for emergency use in August, before beginning a clinical trial to measure its efficacy. But President Vladimir Putin boasted that it was the first vaccine in the world to receive government approval.
Last month, the makers of the Sputnik vaccine reported positive results from a clinical trial, but the vaccine had been tested on a small and unspecified number of people. The final trial has also yet to be completed.
Still, in Moscow, vaccination is now open to workers between the ages of 18 and 60 who face high risks of exposure. Pregnant women and people suffering from a cold or chronic conditions are barred from receiving it.
On Friday, Mayor Sergei Sobyanin said that 5,000 people had registered to get the vaccine, and Deputy Prime Minister Tatiana Golikova cautioned those receiving it to avoid public places and reduce their intake of medicine and alcohol within the first 42 days after the first jab, because it could suppress the immune system, Reuters reported.
Since the beginning of the pandemic, Russia has recorded nearly 2.4 million cases, the fourth-largest number in the world, and more than 41,000 deaths. Moscow, with around 13 million people, has been the epicenter of the country’s outbreak.