Elementary students returned to classrooms in Long Beach, Calif., on Monday and campuses from Los Angeles to Boston prepared for significant expansions of in-person instruction as a majority of the nation’s districts have now begun to reopen school buildings, many of which have been closed for more than a year.
On Monday, Burbio, which monitors some 1,200 districts including the largest 200 in the country, reported that 53.1 percent of students were in schools offering daily, in-person classes, and that for the first time, the proportion of students attending school virtually or in hybrid classes had dropped.
The change, Burbio officials said, appeared to be driven by the return in elementary and middle schools to in-person classes, and by the new rules from the Centers for Disease Control and Prevention permitting schools to allow three feet of social distance instead of six feet in elementary schools.
But a number of roadblocks to reopening remain. On the West Coast, large urban districts generally have lagged behind their counterparts across the rest of the nation. Surging infections in Southern California after the winter holidays were partly to blame for a slow rebound in the Los Angeles school system.
Part of the slow start can be traced to resistance from teachers, whose unions generally are more powerful in Democratic-led Washington, Oregon and California than in many other states, and who have been wary of returning to what they regard as a hazardous workplace, despite federal guidance that elementary schools in particular are safe when health precautions are followed.
Even some schools where teachers have agreed to return are still experiencing setbacks. Schools in Oakland and San Francisco, for example, are scheduled to reopen next month for elementary and special-needs students. But labor agreements in both of those California cities have allowed substantial numbers of teachers to opt out, leaving some schools without enough teachers to reopen and prompting others to scramble for substitutes.
Public schools in California’s top three districts by enrollment — Los Angeles, San Diego and Fresno — have said they will begin to allow grade-school students back onto campus later in April, as new coronavirus cases have fallen sharply statewide.
And on Monday, Long Beach — the state’s fourth-largest district, with about 70,000 students — began allowing about 14,000 elementary students back into school buildings for about 2½ hours each day, five days a week.
The Long Beach school district was able to open earlier than other large California school systems because labor unions there agreed last summer to reopen as soon as health conditions permitted, and because the city was able to start vaccinating teachers earlier than other districts in the state.
Unlike most other cities in Los Angeles County, Long Beach has its own public health department, giving the city its own vaccine supplies and the power to set its own vaccine priorities, at a time when the county as a whole was making teachers wait until after other groups, like residents 65 and older, were vaccinated.
“A city with its own health department has the ability to be more nimble,” said Jill Baker, the city’s schools superintendent, who called the return to classrooms this week “exciting and momentous.”
The school district is among the city’s largest employers, and two-thirds of its students qualify for free or reduced-price lunches, so vaccinating school employees and reopening classrooms was viewed as economically important, Ms. Baker said.
In-person classes for older students are scheduled to resume April 19, with grades 6 to 8 getting the option to return on April 20 and grades 9 to 11 on April 26. The last day of school will be in mid-June.
President Biden, facing a rise in coronavirus cases around the country, called on Monday for governors and mayors to reinstate mask mandates as the director of the Centers for Disease Control and Prevention warned of “impending doom” from a potential fourth surge of the pandemic.
The president’s comments came only hours after the C.D.C. director, Dr. Rochelle Walensky, appeared to fight back tears as she pleaded with Americans to “hold on a little while longer” and continue following public health advice, like wearing masks and social distancing, to curb the virus’s spread. The nation has “so much reason for hope,” she added.
“But right now,” she said, “I’m scared.”
The back-to-back appeals reflected a growing sense of urgency among top White House officials and government scientists that the chance to conquer the pandemic, now in its second year, may slip through its grasp. According to a New York Times database, the seven-day average of new virus cases as of Sunday was about 63,000, a level comparable with late October’s average. That was up from 54,000 a day two weeks earlier, an increase of more than 16 percent.
Public health experts say that the nation is in a race between the vaccination campaign and new, worrisome coronavirus variants, including B.1.1.7, a more transmissible and possibly more lethal version of the virus that has been spreading rapidly. While more than one in three American adults have received at least one shot and nearly one-fifth are fully vaccinated, the nation is a long way from reaching so-called herd immunity — the tipping point that comes when spread of a virus begins to slow because so many people, estimated at 70 to 90 percent of the population, are immune to it.
The warnings come at the same time as some promising news: A C.D.C. report released Monday confirmed the findings of last year’s clinical trials that vaccines developed by Moderna and Pfizer were highly effective against Covid-19. The report documented that the vaccines work to prevent both symptomatic and asymptomatic infections “in real-world conditions.”
The seven-day average of vaccines administered hit 2.76 million on Monday, an increase over the pace the previous week, according to data reported by the C.D.C. On Sunday alone, nearly 3.3 million people were inoculated, said Andy Slavitt, a senior White House pandemic adviser.
Mr. Biden said on Monday that the administration was taking steps to expand vaccine eligibility and access, including opening a dozen new mass vaccination centers. He directed his coronavirus response team to ensure that 90 percent of Americans would be no farther than five miles from a vaccination site by April 19.
The coronavirus vaccines made by Moderna and Pfizer-BioNTech are proving highly effective at preventing symptomatic and asymptomatic infections under real-world conditions, federal health researchers reported on Monday.
Consistent with clinical trial data, a two-dose regimen prevented 90 percent of infections by two weeks after the second shot. One dose prevented 80 percent of infections by two weeks after vaccination.
The news arrives even as the nation rapidly broadens eligibility for vaccines, and the average number of daily shots continues to rise. The seven-day average of vaccines administered hit 2.76 million on Monday, an increase over the pace the previous week, according to the Centers for Disease Control and Prevention.
But the virus may be gaining renewed momentum. According to a New York Times database, the seven-day average of new virus cases as of Sunday was 63,000, an increase of more than 16 percent over the past two weeks.
Similar upticks over the summer and winter led to major surges in the spread of disease, Dr. Rochelle Walensky, director of the Centers for Disease Control and Prevention, said at a news briefing on Monday. She said she had a sense of “impending doom” about a possible fourth surge of the virus.
The nation has “so much reason for hope,” she said. “But right now I’m scared.”
Scientists have debated whether vaccinated people may still get asymptomatic infections and transmit the virus to others. The new study, by researchers at the C.D.C., suggested that since infections were so rare, transmission was likely rare, too.
There also has been concern that variants may render the vaccines less effective. The study’s results do not confirm that fear. Troubling variants were circulating during the time of the study — from Dec. 14, 2020, to March 13, 2021 — yet the vaccines still provided powerful protection.
The C.D.C. enrolled 3,950 people at high risk of being exposed to the virus because they were health care workers, first responders or others on the front lines. None had previously been infected.
Most participants — 62.8 percent — received both shots of the vaccine during the study period, and 12.1 percent had one shot. They collected their own nasal swabs each week, which were sent to a central location for P.C.R. testing, the most accurate type of test. The weekly swabs allowed the researchers to detect asymptomatic infections as well as symptomatic ones.
The investigators asked participants about symptoms associated with infection, including fever, chills, cough, shortness of breath, sore throat, diarrhea, muscle aches, or loss of smell or taste. They also analyzed patients’ medical records to detect illnesses.
Fifty-eight percent of the infections were detected before people had symptoms. Just 10.2 percent of infected people never developed symptoms.
Among those who were fully vaccinated, there were .04 infections per 1,000 person-days, meaning that among 1,000 persons there would be .04 infections in a day.
There were 0.19 infections per 1,000 person-days among those who had had one dose of the vaccine. In contrast, there were 1.38 infections per 1,000 person-days in unvaccinated people.
Dr. Walensky urged Americans to continue taking precautions and to waste no time getting the shots as soon as they are eligible.
“I am asking you to just hold on a little longer, to get vaccinated when you can, so that all of those people that we all love will still be here when this pandemic ends,” she said.
HOUSTON — As Texas joined several other states on Monday in opening eligibility for coronavirus vaccines to millions of healthy adults, anticipation for the shot could be seen in the long line that snaked outside Booker T. Washington High School in Houston.
“This is a good sign,” said Nelson Garcia, 48, who waited more than two hours with his two young children before he was finally within reach of protection from a disease that could be deadly for people with diabetes like himself. “It looks like everyone wants to get vaccinated. I want my children to see that this is a good thing and that the vaccine may finally help us get back to normal.”
On Monday, Texas became the largest state to expand vaccination eligibility to anyone 16 or older, or about 22 million people. Long lines were replicated across the state and appointments were difficult to snag online. Vaccination spots at HEB.com, the website for the most popular supermarket chain in Texas, were few and far between.
The spike was expected. “Virtually anyone can get a vaccine now,” said Representative Sheila Jackson Lee, a Democrat who represents the Houston region.
Five other states, including neighboring Oklahoma and Louisiana, as well as Kansas, Ohio and North Dakota, also opened their doors for all adults on Monday. Several reported increased interest in the vaccine, but the numbers did not overwhelm the system of vaccine providers.
Also on Monday, officials in New York State, once the center of the pandemic with about 31,000 deaths in New York City alone, announced that beginning on Tuesday, all adults 30 and older would be eligible for the vaccine. At least 36 other states have vowed to offer shots to every adult who wants one by mid-April.
Six states — Colorado, Connecticut, Indiana, Minnesota, New Hampshire and South Carolina — plan to expand eligibility this week, officials in those states said.
The German health authority responsible for vaccine guidelines recommended on Tuesday that the country suspend use of AstraZeneca Covid-19 vaccine in adults under 60 because of concerns about a possible association with blood clots. The action came a day after Canada suspended its use in people 55 and under.
Earlier in the day, a number of local authorities in Germany — including Berlin, Munich and the state of Brandenburg — had made similar moves.
A small district in North Rhine-Westphalia banned use of the AstraZeneca vaccine on Monday for all women below the age of 55, after serious episodes last week involving two women who had received it. One, 47, died of sinus vein thrombosis and another, 28, became seriously ill.
No causative link has been established between the patients’ conditions and the vaccine.
Chancellor Angela Merkel met Tuesday evening with state governors to discuss the AstraZeneca vaccine, and said that Germany would follow the recommendation and hold off using it to inoculate people under 60 unless they have discussed the risks with their doctor first.
France and several Nordic countries have also taken a precautionary stance on the vaccine, even after the European Union’s top drug regulator cleared it as safe this month. Some suspensions in Europe may have been driven as much by political considerations as by science.
In Canada, Dr. Caroline Quach-Thanh, the chairwoman of the National Advisory Committee on Immunization, said at a video news conference on Monday that more study was needed. “Given alternative vaccines are available in Canada, N.A.C.I. feels it is very important to study the risks and benefit as a precautionary measure,” she noted.
The Canadian decision was made after reviewing evidence emerging from Germany, where the Paul-Ehrlich Institute, the country’s vaccine regulatory body, reported this month that at least seven people who had recently received the AstraZeneca vaccine had developed a very rare, potentially fatal condition involving blood clots that can block the drainage of blood from the brain, associated with low blood platelet counts (thrombocytopenia) and bleeding. (An earlier version of this item referred incompletely to the condition.)
Statistically, seven cases was significantly higher than normal for the population of 1.6 million adults that had received the vaccine in Germany by March 15, the institute said; by its calculations, just one case would have been expected.
The Canadian health authority continues to recommend the AstraZeneca vaccine for older adults, who are much more susceptible than younger people to serious cases of Covid-19, and have not appeared to develop blood clots in studies conducted in Europe, the committee members said.
“We want to prevent hospitalizations and severe disease for those over 55,” Dr. Quach-Thanh said.
The AstraZeneca vaccine, created by Oxford University, was approved in late February for use in Canada but has suffered setbacks there and elsewhere. Soon after its approval, N.A.C.I. recommended that it not be administered to people 65 and older, because of a lack of data about that age group; two weeks later, N.A.C.I. waived its initial concerns and approved the vaccine for all adults.
The vaccine was the third approved in the country, after those from Pfizer-BioNTech and Moderna. Just over 300,000, or 6 percent, of the doses administered in Canada so far have been AstraZeneca’s vaccine. The Biden administration promised this month to loan Canada 1.5 million more doses of the vaccine, which still has not been approved for use in the United States.
New York can begin vaccinating anyone 30 or older on Tuesday and will make all residents 16 or over eligible on April 6, beating President Biden’s goal of making every adult eligible for a coronavirus vaccine by May 1, Gov. Andrew M. Cuomo announced on Monday.
New York was one of only a few states that had not yet set a timeline for universal adult eligibility. Five states had already expanded eligibility fully by the end of last week; six did so on Monday; seven more will follow later this week, and another six on April 5. At least 11 states have said they will wait until May 1.
Though Mr. Cuomo has gradually loosened vaccine eligibility criteria over the last month, he expressed reluctance last week to set a specific target date for doing away with the state’s requirements. The governor said he did not want to outline a timeline for more widespread vaccination until he was more confident that New York would have adequate vaccine supply on hand for its population.
“I just want to make sure that the allocation projections that we’re getting from the feds are right, frankly,” Mr. Cuomo said at a news conference last week. “I don’t want to say, ‘We’re going to open up to 30-year-olds in three weeks,’ and then something happens with the allocation.”
Mr. Cuomo’s announcement comes as New York has been adding new virus cases at one of the highest rates among U.S. states. As of Monday, the state had a seven-day average of 49 new virus cases a day for every 100,000 residents, according to a New York Times database, second only to New Jersey. (The nation as a whole was averaging 19 new cases per 100,000 people.)
Even as the number of new cases continues to mount, the state has not faced anywhere near the level of devastation that it experienced a year ago, when hospitals were overwhelmed with patients and morgues were overflowing.
Buoyed by its vaccination progress, the state has also been gradually reopening businesses in the last several weeks. Mr. Cuomo allowed sporting events and concerts to resume at large venues last month and movie theaters to bring back audiences this month. Restaurants in New York City are now allowed to serve diners indoors at 50 percent capacity, their highest level of indoor dining since Mr. Cuomo closed them last year at the onset of the pandemic.
As of Monday morning, 29.6 percent of people in New York State had received at least one shot of a vaccine, while 16.8 percent were fully vaccinated, according to the state’s data.
Currently, all people 50 and over are eligible to receive the vaccine in New York, in addition to teachers, some essential workers and people with certain medical conditions that make them more susceptible to serious illness from the virus.
Massachusetts on Monday expanded a new state-financed coronavirus testing program to allow every public school in the state to test all students and staff members weekly for the rest of the school year, using a pooled testing approach that could be a model for school districts nationwide.
More than 1,000 schools in Massachusetts, representing nearly half the districts in the state, are already participating in the program.
Since February, the program has analyzed 22,679 pooled samples from students, teachers and staff members, reporting on Monday a positivity rate of less than 1 percent, considered low. Since the pooled samples typically include swabs from seven different people, state officials said the individual positivity rate is probably much lower.
In a phone interview on Monday, Gov. Charlie Baker said that the state had been able to scale up the program by vetting testing labs and signing contracts with them, instead of leaving each district to do that work on its own. He estimated that the program, which is using federal Covid relief funds to pay for the tests, could cost $30 million to $40 million.
“We started doing it on a demonstration basis with a few school districts just to test it and see if the logistics could work,” Mr. Baker said. “We now have a working model that is operating at a pretty big scale and in a pretty big state.”
The pooled testing program collects nasal swabs from students, faculty and staff members and then tests them in batches, a process that saves time and lab resources. Last week, about 63,000 students and staff members were tested.
If a batch tests negative, everyone in the pool is considered to have a negative result. If a batch tests positive, each person in the pool is then tested.
Massachusetts, which had initially planned to pay for the tests for schools until mid-April, now plans to cover the costs through the end of the school year. It is also encouraging other school districts in the state to sign up.
Mr. Baker said he planned to promote the Massachusetts model to other states. Some districts, like Montgomery County Public Schools, Maryland’s largest system, are planning to introduce pooled testing in April.
“There’s enough money in the various federal bills that have been passed, including the most recent one, to make it possible for states or municipalities both to pay for a program like this,” Mr. Baker said.
The state of New York must immediately begin to offer Covid-19 vaccines to all incarcerated people in the state’s prisons and jails, a judge ruled on Monday, making the state one of few in the nation to provide doses to such a broad population behind bars.
The order, the first involving any of the country’s largest correctional systems, comes as the coronavirus continues to roar through facilities in New York. At least 1,100 people living behind prison walls have tested positive for the virus since the start of last month, and five have died.
But even as corrections staff and many other groups, including some who live in close-contact settings like group homes and homeless shelters, have gained access to the vaccines in recent weeks, most incarcerated people in New York have remained ineligible to receive doses.
Justice Alison Y. Tuitt of State Supreme Court in the Bronx wrote in her ruling on Monday afternoon that people in prisons and jails had been arbitrarily left out of the rollout and that doing so was “unfair and unjust” and an “abuse of discretion.”
State officials, she said, “irrationally distinguished between incarcerated people and people living in every other type of adult congregate facility, at great risk to incarcerated people’s lives during this pandemic.”
She added: “There is no acceptable excuse for this deliberate exclusion.”
Epidemiologists and infectious disease specialists widely agreed, even in the earliest stages of vaccination efforts when supply was more limited, that the roughly 50,000 people in correctional facilities across the state should be made eligible because of their uniquely high risk for contracting and spreading the virus. A disproportionate number of them are also Black and Latino, groups that have been hit hard by the pandemic.
But vaccinating incarcerated people has proved politically fraught across the country, and states grappling with the same ethical, logistical and legal questions have drawn up drastically different timelines for offering doses. In some states, officials have backtracked from plans to vaccinate prisoners because of political headwinds.
In New York, most of those behind bars had been left out, though correctional officers were included and other high-risk groups like restaurant workers, public-facing government employees and essential building service workers have recently become eligible.
State officials announced on Monday that all adult residents would be eligible to receive a coronavirus vaccine by April 6, which might have led more people behind bars to soon be offered doses even had the ruling not been issued.
Vermont is reporting a sharp spike in coronavirus cases, reaching highs that have not been seen since January.
“This is a concerning number of new cases and should not be dismissed,” Dr. Mark Levine, the state’s health commissioner, said at a news conference on Friday.
Vermont hit a single-day case record with 283 new confirmed cases on Friday, according to a New York Times database, making it the first state to set a case record since Jan. 18. (Its seven-day average, 154, is still lower than its peak in January.) Half of the cases reported in the past two weeks were in people under the age of 30, officials said.
The renewed surge has been driven by a number of factors, including pandemic fatigue and the spread of worrisome variants, Dr. Levine said in an interview on Monday. As older people get vaccinated and deaths start to drop, younger people have been more willing to gather in groups, he said.
The University of Vermont has reported a significant increase in confirmed cases among students, climbing to 80 last week from 41 two weeks before. The statewide surge, though, does not appear to be driven largely by college students, Dr. Levine said, since there have not been widespread increases on other campuses.
Cases across the United States have started to rise in recent weeks, after infections began to drop following a post-holiday surge. Scientists have warned for weeks about another increase, as more cases of variants are detected and states lift restrictions. Still, the United States remains behind in its attempts to track variants, though the Centers for Disease Control and Prevention’s efforts to locate them has recently improved and will continue to grow. States in the Northeast have accounted for about 30 percent of the nation’s new cases over the past two weeks, up from 20 percent in early February.
Still, Vermont state officials defended the recent lifting of restrictions, citing a continued drop in deaths and hospitalizations. The state loosened restrictions last week, reopening bars at a limited capacity and allowing restaurants to seat up to six people from different households together. The state still has a mask mandate.
Anne Sosin, a policy fellow at Dartmouth College who has been tracking Vermont’s Covid-19 response since the pandemic’s start, said the lifting of restrictions combined with the spread of new variants could be dangerous. “If we create the conditions for transmission, variants will just exacerbate the impacts of that,” she said.
Vermont opened vaccinations to adults ages 50 and older on Monday, and will expand eligibility to all adults on April 19. About 33 percent of the state’s population has received at least one dose, according to a New York Times vaccine tracker.
“Now that we have a timeline for all Vermonters to get vaccinated, mark your calendar, make your appointment and get your shot,” Dr. Levine said on Friday.
A joint inquiry by the World Health Organization and China into the origins of the coronavirus has yielded a 124-page report full of new detail but no profound new insights. And it does little to allay Western concerns about the role of the Chinese Communist Party, which is notoriously resistant to outside scrutiny and has at times sought to hinder any investigation by the W.H.O.
The report, which was leaked to the media on Monday, a day before its scheduled official release, is also not clear on whether China will permit outside experts to keep digging.
Earlier this year, an international team of experts spent 27 days in Wuhan, the Chinese city where the virus was first detected in late 2019. They visited hospitals, live animal markets and government laboratories, conducted interviews and pressed Chinese officials for data, but came away still far from understanding the origins of the pandemic that has killed nearly 2.8 million people worldwide.
“The investigation runs the risk of going nowhere, and we may never find the true origins of the virus,” said Yanzhong Huang, senior fellow for global health at the Council on Foreign Relations.
The report says that China still does not have the data or research to indicate how or when the virus began spreading. Some skeptics outside the country say that China may have more information than it admits.
The expert team also dismisses as “extremely unlikely” the possibility that the virus emerged accidentally from a Chinese laboratory, even though some scientists say that is an important question to explore.
The Chinese government, while granting some degree of access and cooperation, has repeatedly tried to bend the investigation to its advantage. The report was written jointly by a team of 17 scientists from around the world, chosen by the W.H.O., and 17 Chinese scientists, many of whom hold official positions or work at government-run institutions, giving Beijing great influence over its conclusions.
Jesse Bloom, an evolutionary biologist at the Fred Hutchinson Cancer Research Center in Seattle, said after seeing a copy of the report that he was not convinced that a laboratory leak was extremely unlikely. He said he agreed with the report that the virus could have come from a natural zoonosis, but he did not see any reasoning in the report to dismiss the possibility of a lab escape.
One member of the team of experts, Peter Daszak, a disease ecologist who runs EcoHealth Alliance, pushed back against the criticism of the team’s work and of China’s level of cooperation, calling the lab leak hypothesis, which has been promoted by some Trump administration officials, “political from the start.”
The prevailing theory remains that the virus originated in bats, jumped to another animal, and then mutated in a way that enabled it to transmit to humans, and from human to human. But the process of tracing the origins of a virus is notoriously painstaking.
To answer numerous remaining questions, the report recommends further retrospective studies of human infections, including the earliest cases, and more virus testing of livestock and wildlife in China and Southeast Asia. But it is unclear to what degree China would cooperate.
In Washington on Monday, the White House press secretary, Jen Psaki, said experts across the U.S. government, including leaders in veterinary medicine and biosecurity, were currently reviewing the report.
“We have been clear that an independent, technically sound investigation is what our focus is on, and once this is reviewed we’ll have an assessment about the steps forward,” she said.
Earlier in the day, Dr. Anthony S. Fauci, the leading expert in infectious diseases in the United States, and Dr. Rochelle Walensky, the head of the Centers for Disease Control and Prevention, said they had not yet seen the report.
The Education Department said on Monday that it would abolish the federally subsidized college debts of thousands of students who are disabled and also end paperwork requirements for tens of thousands more — moves aimed at relieving student loan debt made worse by the pandemic.
The agency said the changes would benefit 41,000 disabled borrowers with $1.3 billion in student loans whose debts were forgiven, but then reinstated, because they failed to supply income information during the pandemic. Another 190,000 borrowers whose debts have been forgiven will not have to submit paperwork during the pandemic.
Under Education Department rules, student loan borrowers who are permanently disabled and cannot work may have their debts waived. During a three-year period after they are granted debt relief, they must submit income data proving that they remain unable to work.
A 2016 report by the Government Accountability Office, however, found that 98 percent of the disabled borrowers whose discharged loans have been reinstated were unable to fill out the necessary paperwork.
The announcement came as the Biden administration said it is reviewing ways to alleviate the burden of student loan debt generally. President Biden has proposed forgiving $10,000 in student loan debt for borrowers as some congressional Democrats, including Senator Chuck Schumer, the majority leader, push for even greater relief.
In a related announcement this month, the Education Department said it would scrap a Trump administration policy limiting defrauded students from seeking debt forgiveness.
Reacting to Monday’s announcement on disabled borrowers, Student Defense, a nonprofit education advocacy organization, said it did not go far enough, urging loan forgiveness for an additional 400,000 disabled borrowers with $14 billion in outstanding loans.
In interviews broadcast on CNN Sunday night, former President Donald J. Trump’s pandemic officials confirmed in stark and no uncertain terms what was already an open secret in Washington: The administration’s pandemic response was riddled with dysfunction, and the discord, untruths and infighting most likely cost many lives.
Dr. Deborah L. Birx, Mr. Trump’s coronavirus response coordinator, suggested that hundreds of thousands of Americans may have died needlessly, and Adm. Brett P. Giroir, the testing czar, said the administration had lied to the public about the availability of testing.
The comments were among a string of bombshells that emerged during a CNN special report that featured the doctors who led the government’s coronavirus response in 2020.
Dr. Robert R. Redfield, the former director of the Centers for Disease Control and Prevention, accused Mr. Trump’s health secretary, Alex M. Azar III, and the secretary’s leadership team of pressuring him to revise scientific reports. “Now he may deny that, but it’s true,” Dr. Redfield said in an interview with Dr. Sanjay Gupta, CNN’s chief medical correspondent. Mr. Azar, in a statement, denied it.
Dr. Stephen K. Hahn, the former commissioner of the Food and Drug Administration, said his relationship with Mr. Azar had grown “strained” after the health secretary revoked the agency’s power to regulate coronavirus tests. “That was a line in the sand for me,” Dr. Hahn said. When Dr. Gupta asked him if Mr. Azar had screamed at him, Dr. Hahn replied: “You should ask him that question.”
But it was Dr. Birx, who has been pilloried for praising Mr. Trump as being “so attentive to the scientific literature” and for not publicly correcting the president as he made outlandish claims about unproven therapies, whose disclosures may have been the most compelling.
As of Sunday, more than 548,000 Americans have died from infection with the coronavirus. “I look at it this way,” she said. “The first time, we have an excuse. There were about 100,000 deaths that came from that original surge.”
“All of the rest of them,” she said, referring to almost 450,000 deaths, “in my mind, could have been mitigated or decreased substantially” had the administration acted more aggressively.
In what was one of her first televised interviews since leaving the White House in January, she also described a “very uncomfortable, very direct and very difficult” phone call with Mr. Trump after she spoke out about the dangers of the virus last summer. “Everybody in the White House was upset with that interview,” she said.
After that, she decided to travel the country to talk to state and local leaders about masks and social distancing and other public health measures that the president didn’t want her to explain to the American public from the White House podium.
Dr. Gupta asked if she was being censored. “Clearly someone was blocking me from doing it,” she said. “My understanding was I could not be national because the president might see it.”
Several of the officials in the interview, including Dr. Anthony S. Fauci — who unlike the others is a career scientist and is now advising President Biden — blamed China, where the virus was first detected, for not being open enough with the United States. And several, including Dr. Redfield and Admiral Giroir, said early stumbles with testing — and the attitude within the White House that testing made the president look bad by driving up the number of case reports — were a serious problem in the administration’s response.
And the problems with testing went beyond Mr. Trump’s obsession with optics. Admiral Giroir said that the administration simply did not have as many tests as top officials claimed at the time.
“When we said there were millions of tests — there weren’t, right?” he said. “There were components of the test available but not the full deal.”
In a lengthy statement Monday evening, Mr. Trump shot back at Dr. Fauci and Dr. Birx, blasting them as “two self-promoters trying to reinvent history to cover for their bad instincts and faulty recommendations,” while praising his administration’s efforts to develop a vaccine.
The former president, who routinely questioned the need for lockdowns and other precautions during his administration, said of Dr. Fauci and Dr. Birx, “If it were up to them, we’d currently be locked in our basements as our country suffered through a financial depression.”
The Centers for Disease Control and Prevention has extended its nationwide moratorium on evictions through June 30, pushing it back from the end of March, when it had been scheduled to lapse.
The move, while widely expected, comes at a precarious moment in the pandemic as the increasing vaccine availability accelerates reopening plans by businesses and local governments — even as millions of families continue to struggle with hardships that might have led to mass evictions.
The C.D.C. issued the moratorium last fall, citing its jurisdictional authority to implement measures needed to promote public health, and agency officials cited those same powers in extending the moratorium on Monday.
“The Covid-19 pandemic has presented a historic threat to the nation’s public health,” the agency’s director, Rochelle P. Walensky, said in a statement. “Keeping people in their homes and out of crowded or congregate settings — like homeless shelters — by preventing evictions is a key step in helping to stop the spread.”
Under President Biden, the Department of Housing and Urban Development earlier this year extended its own foreclosure and eviction moratorium for federally financed housing to June 30. (An earlier version of this item misstated the status of that moratorium. It was extended in February.)
The new housing secretary, Marcia L. Fudge, has signaled that she would like to extend her agency’s eviction freeze even longer. Department officials have reached out to community groups to elicit suggestions on how to streamline the new rule.
The administration’s $1.9 trillion relief package, passed this month, includes $21.5 billion for emergency rental assistance, $5 billion in emergency housing vouchers, $5 billion for homelessness assistance and $850 million for tribal and rural housing. But that aid will take months to be disbursed.
Initially, the C.D.C. ban was riddled with loopholes that allowed some landlords to evict some tenants. But over all, it helped to create a significant drop in eviction applications filed in local housing courts.
The federal moratorium is part of a patchwork of federal, state and local efforts to prevent a national health and economic emergency from turning into a monumental housing collapse.
Most states — 43 in all, plus Washington, D.C. — have temporarily halted evictions during the crisis. But the range of protections varies wildly and some tenants, including in the New York City neighborhoods hit hardest by the pandemic, have been displaced because they were unaware of the protections.
As many as one in five renters said they did not pay last month’s rent, according to Census Bureau surveys, with a third of Black renters reporting a recent missed payment.
Hong Kong officials said Monday that residents stranded in Britain would be allowed to return starting next month, as they announced the easing of multiple coronavirus restrictions.
Hundreds of Hong Kong residents have been stuck in Britain since late December, when the Chinese territory abruptly announced a ban on direct travel from the country after the emergence there of a highly contagious variant of the virus. Starting in the second half of April, they will be allowed to return to Hong Kong on designated flights, officials said. They did not mention any change to similar bans on arrivals from Brazil, Ireland and South Africa.
Hong Kong’s quarantine requirements, which are among the strictest in the world, will also be eased for travelers arriving from “low-risk” countries like Australia, New Zealand and Singapore, including nonresidents, who would be the first allowed to enter the city since foreigners were barred last March. Instead of quarantining at designated hotels for 21 days, they will only have to quarantine there for 14 days followed by seven days of self-monitoring. The Hong Kong border remains closed to nonresidents from other countries. (An earlier version of this item described incorrectly the border policy.)
Other changes appeared aimed at rejuvenating the city’s struggling vaccination effort. The government announced that it would lift visitation restrictions at hospitals and nursing homes for those who have been inoculated and end mandatory coronavirus testing for restaurant, school and construction workers who are fully vaccinated.
Only 6 percent of Hong Kong’s 7.5 million people have been vaccinated since the campaign began in February. The program suffered a setback last week when packaging defects were discovered in a batch of doses of the Pfizer-BioNTech vaccine, prompting health officials to suspend its use.
Over the weekend, Hong Kong said that a preliminary investigation by BioNTech of Germany and Fosun Pharma — the Chinese company responsible for distributing the vaccine in Hong Kong — found no systematic problems in its shipments. Health officials said that the vaccine remained safe to use and that they would resume administering it “as soon as possible.”
Aside from the Pfizer-BioNTech vaccine, the only other vaccine authorized for use in Hong Kong is the one developed by the Chinese company Sinovac. Polls have shown that the majority of Hong Kong residents are reluctant to take any vaccine, but they are especially wary of Sinovac after reports that several people had died after receiving it. Officials have found no direct link between the shots and the deaths.
The loosening of restrictions comes as Hong Kong is emerging from a fourth wave of infections that began in late November. For two days over the weekend, the city reported zero local cases for the first time in more than four months. On Monday, one local case was reported.
The number of people who have died from Covid-19 in Mexico may be more than 50 percent higher than the official count, new government figures show: The virus may have claimed more than 300,000 lives, a staggering toll for the country of 126 million.
The Mexican government updated its mortality statistics on Saturday, showing that from the start of the pandemic through mid-February, some 294,000 deaths were directly associated with the virus — far exceeding the official toll of about 184,000 recorded up to that point.
Adding official deaths registered since mid-February, the country’s actual coronavirus death toll now appears to stand above 310,000 — more than 50 percent higher than the 201,623 deaths currently recorded on the Mexican government’s coronavirus tracking website.
Extremely low levels of testing and a widespread fear of hospitals in Mexico have led to a severe undercount of the pandemic’s true cost, with many cases only confirmed as virus-related upon a later revision of death certificates.
The updated numbers showed that there was a total of 417,000 more deaths over all in Mexico than would have been expected in the period since the pandemic began, a figure known as excess mortality. That figure suggests that the pandemic’s true impact could be even higher.
Mexico is struggling with a glacial vaccination campaign: According to Johns Hopkins University, less than 1 percent of the population has been fully vaccinated so far.
On Sunday, 1.5 million doses of the AstraZeneca vaccine arrived in Mexico from the United States, part of a total of 2.7 million doses being sent to Mexico as part of an agreement with President Biden.
KATHMANDU, Nepal — Nepal on Monday received a donation of 800,000 doses of a Covid-19 vaccine from China, which the authorities said would help them restart an inoculation drive that had been halted because of shipment delays in India.
Dr. Jageshwor Gautam, a spokesman for the ministry of health, said the vaccination campaign could resume in less than a week, “once we determine beneficiary age groups.”
China and India, both of which border Nepal, have been jockeying for influence over the Himalayan nation of 30 million people, most recently through vaccine diplomacy.
Nepal had planned its vaccination campaign around the Oxford-AstraZeneca vaccine manufactured by the Serum Institute of India, the world’s largest vaccine producer. One million doses have been donated by the Indian government, and Nepal had bought an additional two million doses from the Serum Institute.
But half of the purchase from the Serum Institute has been delayed indefinitely, health officials in Nepal said, despite an agreement that it would arrive 15 days after the deal. India, which is supplying the AstraZeneca vaccine to more than 70 countries, has begun holding back nearly all of its exports as it tries to suppress a surge in coronavirus cases at home.
Officials in Nepal suspended vaccinations on March 17, citing the shortage of doses.
To fill the gap, they are now relying on a vaccine developed by the Chinese company Sinopharm, which last month became the second approved for emergency use in Nepal after Beijing pledged to provide doses free.
Since its vaccination drive began in late January, Nepal has administered about 1.6 million doses, according to a New York Times database. Dr. Gautam said the 500,000 remaining AstraZeneca doses would be given to frontline health workers, and that there were none available for the rest of the population “at least for now.”
Nepal has recorded almost 277,000 infections and 3,027 deaths, according to a New York Times database. Although the country’s average daily new cases are a small fraction of what they were at their peak last fall, health officials fear a second wave as infections surge in neighboring India. On Monday, India reported 68,020 new infections, the highest one-day rise since October.
Johnson & Johnson said on Monday that it would supply its one-shot Covid-19 vaccine to African Union member states, as the continent experiences a slow rollout of vaccines, an uptick in cases and worries about new mutations of the coronavirus.
The pharmaceutical company said that its unit, Janssen Pharmaceutica NV, had agreed to a deal with the African Vaccine Acquisition Trust, an African Union organization, to supply up to 220 million doses of its Covid-19 vaccine beginning in the fall. The organization will also have the option to order an additional 180 million doses for a combined total of up to 400 million doses through 2022.
The company will supply most of the doses from a plant in South Africa, which is operated by Aspen Pharma. The African Export-Import Bank, a pan-African bank based in Cairo, will pay manufacturers $2 billion on behalf of member countries in the form of loans.
South Africa’s president, Cyril Ramaphosa, who as chairman of the African Union set up the vaccine trust last year, was expected to tour the Aspen Pharma facilities in Port Elizabeth, on the country’s southeast coast, on Monday.
“This agreement is a significant milestone in protecting the health of all Africans,” Mr. Ramaphosa said in a statement. “It is also a powerful demonstration of African unity and of what we can achieve through partnership between the state sector, the private sector and international institutions that puts people first.”
The announcement came as coronavirus cases surpassed 4.1 million in Africa, with more than 111,000 deaths, according to the Africa Centers for Disease Control and Prevention. Concerns have been mounting about the emergence of variants on the continent, particularly in countries like South Africa, where a highly transmissible variant has driven up cases. Scientists also recently said they found a highly mutated variant of the coronavirus in travelers from Tanzania, the East African nation whose leaders have consistently brushed aside the virus threat.
Besides facing other deadly outbreaks including Ebola, polio and measles, many nations in Africa are also dealing with vaccine inequity, as developed nations hoard doses and seek to inoculate their entire populations. So far, only 7.7 million vaccines have been administered on the continent, according to the World Health Organization, which last week warned of a slowdown in deliveries even as initial batches were exhausted.
Vaccines have yet to arrive in 10 African countries, the W.H.O. said, while many others continue to face logistical challenges in addition to vaccine hesitancy.
Nations including South Africa have called on governments and pharmaceutical companies to waive vaccine patents to get medicines to more people more quickly.
The Africa C.D.C. has said that at least 60 percent of the continent’s population — or 750 million people — must be vaccinated if the virus is to be curbed there. The deal with Johnson & Johnson “enables Africa to meet almost 50 percent of that target,” Dr. John Nkengasong, the head of the Africa C.D.C., said in a statement.
“The key to this particular vaccine is that it is a single-shot vaccine, which makes it easier to roll out quickly and effectively, thus saving lives,” he added.
Palakiko Chandler took their little cousins to Nanakuli Beach on Oahu last weekend and noticed something they hadn’t seen in a while: a parking lot full of rental cars. The tourists were back.
“It was just so packed,” said Mr. Chandler, 27 and a Native Hawaiian. “Me and my cousins were looking at each other like, should we just go home?” The youngest cousins needed several reminders to keep their distance from strangers for virus safety.
For much of the pandemic, Hawaii had some of the strictest rules for visitors in the United States, requiring a 14-day quarantine for everyone arriving in the islands. The policy took a heavy economic toll on a state that depends heavily on tourism, but it was lauded for its success in limiting the impact of the virus for months.
Now, though, Hawaii has reopened for travelers: A negative test within 72 hours of arrival lets them skip the quarantine in most places. At least 28,000 people arrived in Hawaii on each of the last two Saturdays, according to state travel data — the most in a day since the pandemic began, and not far from typical prepandemic levels.
The influx has residents worried. Some have been posting on social media for months, pleading with mainlanders not to come, or if they do, to be mindful of the islands’ isolation and limited resources. The state has a total of 3,000 hospital beds for its population of 1.4 million, and has among the fewest I.C.U. beds per capita of any state; they were often mostly full even before the pandemic.
Hawaii’s precautions did not keep the virus out completely: The islands had a holiday surge, like the rest of the country, and parts of the state are struggling with outbreaks now. Daily new case reports have doubled since late February, with some recent clusters focused on tourism workers. Hospitalizations have increased 17 percent in the last two weeks.
“The looming concerning things are the variants,” said Dr. Damien Kapono Chong-Hanssen of the Kauai Community Health Center. “The California variant has been implicated in what’s happening in Maui right now. Maui is not looking better.”
Mainlanders are making the trip anyway. “Hawaii is again packed with tourists,” wrote the travel site The Points Guy. Favorite sites are sold out, check-in lines are long, and the lines for outbound flights are getting longer.
Tourists are crowding popular beaches without wearing masks or paying much attention to social distancing. Some visitors have gotten rowdy. A pair of arriving tourists were sent home after trying to pay a bribe to avoid the testing requirement.
The situation is worsening the irritation that many state residents feel toward vacationers. Now the tourists aren’t just crowding the island and driving up prices, they say, they are also heedlessly risking everyone’s health.
“Hawaiians and locals alike have always seen the disrespect that tourists bring to our islands,” Mr. Chandler said. “This is kind of the last straw. You’re coming to our home and you’re endangering us during a pandemic.”
“Local people are tired of being treated a certain type of way,” said Charles Kaua Taylor-Fulton, 20, who lives on Oahu. “When tourists come, they can be very rude or entitled. There’s just a sense of entitlement.”
Dr. Lee Buenconsejo-Lum of the University of Hawaii at Manoa said the state’s case numbers are not exploding, at least not yet. But she said she would like to see travelers exhibit the same commitment to wearing masks that locals have. “It’s a matter of constantly educating the tourists,” she said.
Still, the high travel season is just getting started, and restrictions are continuing to ease. Bars have reopened in parts of the state and outdoor weddings are now allowed to welcome up to 100 guests.
“We can already see into the future of summer,” Mr. Chandler said, “and it’s going to be packed.”
With more than 30 million people at least partially inoculated against Covid-19, Britain on Monday began a gradual lifting of coronavirus restrictions for most of its population.
People in England are now allowed to gather outdoors in groups of up to six, or two households, after the end of a stay-at-home order in force since early January.
Outdoor sports facilities, like tennis and basketball courts and swimming pools, are also opening in England. Nonessential retail and outdoor dining are set to return starting April 12. Students returned to classes earlier this month. Elsewhere in Britain, Scotland and Wales have also begun easing stay-at-home orders, and Northern Ireland is set to review coronavirus restrictions next month.
For many in Britain, the easing was a cautious optimistic note after months of lockdown, the nation’s third. The current lockdown began in January, after a new variant of the coronavirus swept the country, with as many as 60,000 daily cases and 1,800 daily deaths at its winter peak. On Sunday, the country reported 3,862 cases and 19 deaths, according to a New York Times database. London has so far reported no deaths from the virus on Sunday, according to Public Health England. If no reports are added later — the figures are not yet finalized — it would be the capital’s first day without a virus death since September. Officials are hoping a slow lifting will largely remove restrictions on socializing in England by June 21.
Travel abroad for English residents, however, remains banned, with a task force reviewing the rule next month. Officials cautioned that people should still work from home where possible and minimize contact.
In other news from around the globe:
In Australia, officials in Brisbane said Tuesday that they had found two clusters of new infections, both linked to unvaccinated frontline health workers. Eight cases were reported overnight, making it 15 new cases in total over the past few days in Australia’s third-largest city. Brisbane is under a three-day lockdown after tests showed the virus spreading in the city is the highly contagious variant first detected in Britain.
The capital region of the Philippines entered the country’s highest level of lockdown on Monday. Under what is known as enhanced community quarantine, which is set to last until Easter Sunday, Manila and four surrounding provinces are under curfew from 6 p.m. to 5 a.m. People under 18 and over 60, as well as pregnant women and those with chronic health conditions, are instructed to stay home at all times. The capital region, which is home to more than 25 million people, had been on the second-highest level of lockdown since March 22.
More than three months after the nation’s health care workers were among the first Americans to be eligible for the lifesaving vaccines, long-term-care facilities across the country continue to face the daunting challenge of getting their staff members inoculated.
The federal program that sent vaccinators from Walgreens and CVS into tens of thousands of nursing homes and assisted living residences has by one measure been strikingly successful, inoculating nearly all of the vulnerable residents of the facilities. Deaths in nursing homes have plummeted since the program began in late December.
But reaching the mostly low-wage employees of the facilities has proved far more difficult. A poll by The Washington Post and Kaiser Family Foundation conducted from Feb. 11 to March 7 found that half of the workers at nursing homes had yet to get even a first shot, and only 15 percent of that group said they definitely planned to.
At Forest Hills of D.C., a nursing home in a prosperous neighborhood of the nation’s capital, the workers who turned down the vaccine during the center’s first vaccination event in early January included nurses, certified nursing assistants, members of the kitchen and activities staffs, and a security officer.
Most were Black, reflecting the overall makeup of the home’s work force; many were immigrants from African countries, such as Nigeria, Liberia and Cameroon.
Across the country, vaccine hesitancy has been receding — a Pew poll conducted in late February found that 30 percent of Americans said they would probably or definitely not get vaccinated, down from the 39 percent who said the same in November. The poll also found that far more Black Americans were willing to get the vaccine than they were before.
Still, the challenges remain. The Times took a closer look at Forest Hills and its efforts to vaccinate the employees over the first three months of this year.
The pandemic has brought grinding frustrations for parents, educators and students across the United States. But perhaps no place has matched San Francisco in its level of infighting, public outrage and halting efforts to reopen schools.
In February, the city sued its own school system, which has been entirely remote for a year, and board of education, accusing them of violating state law by not resuming in-person instruction.
Soon after, two parents infuriated by the school board’s decision to rename 44 schools, even as it kept them closed, started a drive to recall three of the board members. Some 9,000 people have joined the campaign’s mailing list, and they are expected to begin collecting signatures soon.
Then critics of the board unearthed four-year-old tweets written by the board’s vice president in which she accused Asian-Americans of sidling up to white Americans to get ahead without confronting racism, comparing them to slaves who benefited from working inside a slave owner’s house. More than a third of the district’s students are Asian-American.
Amid the chaos, one thing has remained clear: A large share of the city’s public school students are unlikely to see the inside of their classrooms this academic year.
The district has set dates in mid-to-late April to start bringing back elementary students and some high-needs older students, but there is no plan yet for the majority of middle or high school students to return. At the same time, all of the roughly 10,000 teachers and staff members in the district have been offered vaccinations.
In the realm of education, the pandemic has reinforced the notion of a city divided by wealth and race. Around one-third of the city’s schoolchildren, many of them white, go to private schools, one of the highest rates of any major city in the United States. Many of those private-school students have been sitting in classrooms for months while public school students, who are disproportionately Black, Latino and Asian-American, have spent the year in virtual classes.