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Negotiations to break the stimulus stalemate end with no compromise in sight.

Top Democrats and the White House clashed anew on Thursday over an economic recovery package as a jobs report loomed over stalled negotiations on the plan, raising the stakes of the talks even as a compromise appeared to be nowhere in sight.

After more than three hours in the Capitol Hill offices of Speaker Nancy Pelosi, negotiators emerged without an agreement and said stark divisions remained. Ms. Pelosi, of California, described a “consequential meeting” where “we could see the difference in values that we bring to the table.”

Mark Meadows, the White House chief of staff, and Steven Mnuchin, the treasury secretary, offered equally pessimistic remarks after meeting with Ms. Pelosi and Senator Chuck Schumer of New York, the minority leader. “We’re still a considerable amount apart,” Mr. Meadows told reporters.

“If the basis is getting an overall deal done, there would have to be significant compromises on some big issues tomorrow,” Mr. Mnuchin said, adding that he expected the negotiators to speak by phone the next day to “see if it makes sense to meet.”

The Labor Department will report Friday morning on how many jobs the economy created in July, as America climbs back from the depths of the pandemic recession. Forecasters expect fewer new jobs than in May, when the nascent recovery added 2.7 million jobs, or June, when it added 4.8 million. That’s because the resurgence of the coronavirus has cooled growth in consumer spending and business activity for much of this summer.

The economy remains down more than 10 million jobs from its pre-pandemic peak in February. If Friday’s report shows a drastic slowdown in job creation, pressure will rise on Mr. Trump and congressional leaders to cut a deal to provide additional aid for struggling small businesses, laid-off workers and state and local governments that face large shortfalls in tax revenue amid the crisis. New claims for unemployment benefits have exceeded 1 million a week for 20 straight weeks, the Labor Department reported on Thursday.

A better-than-expected report on Friday could sway Mr. Trump — who has said repeatedly that the economy would rapidly return to its pre-crisis state — against agreeing to Democrats’ demands on issues like extending the now-expired $ 600-a-week federal supplement for unemployed workers.

Mr. Trump escalated his threat on Thursday to walk away from the negotiations and act unilaterally instead. He told reporters he was considering issuing executive orders to forestall evictions, suspend payroll tax collection and provide extra unemployment aid and student loan relief, perhaps as soon as Friday or Saturday.

It is not clear that he has the legal authority for some of those moves, given that spending power lies with Congress. But a White House official said lawyers there believe Mr. Trump would be on solid ground to use money provided in the last stimulus measure but not yet spent. Democrats rejected the idea, calling it illegal and insufficient.

“Congress has the power of the purse, and President Trump has no authority to deviate from spending decisions the House and Senate made in previous coronavirus relief bills,” said Evan Hollander, a spokesman for the Democrats on the House Appropriations Committee.

Also on Thursday, a federal judge dismissed a lawsuit filed by Republicans against Ms. Pelosi that sought to block the House of Representatives from using a proxy voting system to allow for remote legislating during the pandemic.

Judge Rudolph Contreras, of the Washington, D.C., District Court, wrote in his opinion that “the House unquestionably has the authority, under the Constitution, to ‘determine the rules of its proceedings,’” and affirmed that legislative work undertaken by Ms. Pelosi and other top Democrats was “immune from suit under the speech or debate clause” of the Constitution.

Ohio’s governor, who offered a stark virus warning, tests positive — then negative.

Gov. Mike DeWine of Ohio tested negative for the coronavirus on Thursday, hours after a positive rapid-result test prevented him from welcoming President Trump to the state.

The whiplash of contradictory results reflects the country’s limited ability to slow the spread of the virus with widespread and accurate testing.

Governor DeWine’s test results came two days after he implored residents to avoid large gatherings because of the risk of spreading the virus to family and friends. He initially tested positive for the virus while being screened to greet President Trump in Cleveland on Thursday, his office said.

“The lesson that should come from this is, we’re all human,” Mr. DeWine, 73, said on Thursday afternoon, standing on the porch at his home while waiting for the results of his second test. “The virus is everywhere.”

But a second test, administered later in the day, came up negative. Mr. DeWine’s wife, Fran, and staff members also tested negative.

The first test was an antigen test, a new frontier of testing that allows for results in minutes, not days, but has been shown to be less accurate. The second was a more standard process known as polymerase chain reaction, or P.C.R., an accurate but time-intensive method that requires samples to be processed at a laboratory.

Most coronavirus tests in the United States have so far relied on P.C.R., but severe supply shortages have slowed the turnaround of results, stretching to more than a week — or three — in some parts of the United States. That has complicated, efforts to detect and track the spread of the virus.

The best chance to rein in the sprawling outbreaks, experts say, requires widespread adoption of less accurate tests, as long as they are administered quickly and often enough.

Mr. DeWine, a Republican who has stood out for his studious virus briefings and aggressive response, was tested as part of a standard protocol in order to greet Mr. Trump on the tarmac of Burke Lakefront Airport in Cleveland.

Mr. DeWine did not meet with the president, who was scheduled to speak about rebuilding the economy during a stop in Cleveland and then tour a Whirlpool plant in Clyde. While he was there, Mr. Trump signed a long-awaited executive order requiring the federal government to purchase certain pharmaceuticals and medical supplies and equipment from American factories.

Mr. DeWine was not experiencing symptoms, and was headed back to Columbus, where he plans to self-isolate for 14 days, his office said.

At least 26 new coronavirus deaths and 1,199 new cases were reported in Ohio on Wednesday. Over the past week, there have been an average of 1,202 new cases per day, a decrease of 11 percent from the average two weeks earlier. The state has recorded 96,305 cases and 3,596 deaths since the beginning of the pandemic, according to a New York Times database.

Mr. DeWine is the second governor in the nation known to have tested positive. Gov. Kevin Stitt of Oklahoma, a Republican, received a positive test result last month.

U.S. ROUNDUP

Nine of the U.S.’s 10 largest school districts will begin the school year online.

The school board in Hillsborough County, Fla., voted on Thursday to start the school year on Aug. 24 with remote instruction only for at least four weeks, and possibly longer.

The decision means that all but one of the 10 largest school districts in the United States have decided not to reopen with face-to-face instruction at the start of the school year because of concerns about the continuing spread of the coronavirus. The exception is New York City schools, which are planning a hybrid approach.

The Hillsborough board said it made its decision after hearing from a panel of health professionals, and that it would review the situation on Sept. 8 to decide what to do after the first four weeks.

Hillsborough County, which includes the city of Tampa and some of its suburbs, has grown rapidly in population in recent years. Like the rest of Florida, it has experienced a surge in coronavirus cases since mid-June, including more than 2,900 new cases in the last seven days, according to a New York Times database.

In other U.S. news:

• More than 57,330 cases and 1035 deaths were reported in the United States on Thursday. Indiana reported more than 1,050 new cases, a single-day record.

• After reports of large parties in recent weeks, the mayor of Los Angeles said on Wednesday that the city could cut off power to homes or businesses that host large gatherings in defiance of public health guidelines.

• Republicans and Democrats in Congress say they agree that a new stimulus package must include billions of dollars to help schools struggling financially and logistically to resume education this month and next. But the parties are digging in over profound ideological differences, especially the divide between Democratic demands for public education spending and a Republican push to channel federal dollars into vouchers that families could use at private schools willing to open for in-person classes.

• President Trump on Thursday signed a long-awaited executive order that would require the federal government to purchase certain pharmaceuticals and medical supplies and equipment from American factories. Politicians from both parties have criticized America’s dependence on China and other nations for drugs and medical supplies. Pharmaceutical lobbyists, business groups and economists had opposed the rule change, saying it could further disrupt supply chains and result in higher drug prices.

A broken health reporting system in California muddies the picture of the outbreak.

Counties across California have posted messages warning the public not to rely on their coronavirus data dashboards after the state said that the system used to collect and disseminate case data was broken.

A note on the website of Santa Clara County, in Silicon Valley, said that it was “impossible for State and local health officials to identify the extent to which Covid-19 is circulating in the community.”

Gov. Gavin Newsom announced Monday that the seven-day average of cases had fallen by around 20 percent in the state, but officials now say the underreporting of cases puts that decline into question.

California is America’s hub for technology and a major center for biotech companies, but the state has struggled to track the progression of the virus in two key ways: the breakdown in the data sharing system — which Mayor Eric Garcetti of Los Angeles said Wednesday may have begun months ago — and huge lags in providing testing results.

Contra Costa County, across the Bay from San Francisco, is taking at least 16 days to process tests at its drive-through centers, according to county officials. Other counties in the state are returning results after a week or more.

Dr. Bob Wachter, the chairman of the department of medicine at the University of California, San Francisco, said that a test that takes weeks to process is “a worthless piece of information.”

“In order to get back to work and open schools we have to have intimate knowledge of who’s got the virus and who’s been in contact with someone who’s got the virus,” Dr. Wachter said. “If you can’t do that within a day or two, the whole system falls apart very rapidly.”

Mark Ghaly, the state’s health and human services secretary, told reporters on Tuesday that “discrepancies” in the data dissemination system, known as CalREDIE, would “absolutely” affect the test positivity rates, but he did not say by how much.

Hospitalization rates, which are reported using a different system and have been falling, continue to be accurate, he said.

A spokeswoman for the California Department of Public Health, Ali Bay, could not say when the data dissemination system would be fixed.

“Our team continues to work around the clock to address the underreporting issue,” she said.

China’s exports rise despite the virus, surprising economists.

China’s exports rose last month at their fastest pace so far this year, the country’s General Administration of Customs announced on Friday.

Chinese factories ran at full throttle this summer, after the government brought the coronavirus almost completely under control within the nation’s borders. Exports were up 7.2 percent in July compared with a year ago, far above what economists had predicted — and even as the pandemic continued to ravage other nations’ economies.

By contrast, the value of China’s imports actually shrank 1.4 percent last month, a worse performance than the modest increase economists had expected. The physical volumes of China’s imports kept rising last month, but that was more than offset by a global fall in prices for oil and other commodities that the country buys from abroad.

The combination of rising exports and cheaper imports means that China’s trade surplus is widening sharply. That could trigger trade tensions in the months ahead, particularly as other countries face job losses from economic slowdowns triggered by the virus.

Despite Friday’s strong export data, share prices had fallen 1.7 percent by early afternoon on China’s stock exchanges. Investors worried about President Trump’s executive order on Thursday that announced broad restrictions on two popular Chinese social media networks, TikTok and WeChat.

Embattled on all sides, Birx presses on against the coronavirus.

Dr. Deborah L. Birx, the White House coronavirus response coordinator, has increasingly found herself a woman without a country.

Dr. Birx serves as a link between federal agencies engaged in the pandemic response and the point of contact for state and local officials. A political appointee, she took her post five months ago and serves at the pleasure of the president.

In recent weeks, old allies and public health experts have expressed disgust at her accommodations to Mr. Trump and, more so, at the performance of the federal response she is supposed to be leading against the most devastating public health crisis in a century.

Some fault her for offering unduly rosy assessments of the pandemic, both in public and in private. In April, she told officials in the White House Situation Room that the United States was in good shape.

But inside the White House, aides refer to Dr. Birx as “Dr. Doom” for her efforts to temper the president’s positive spin. Mr. Trump called her “pathetic” on Monday after she suggested the obvious: The coronavirus is in a “new phase” and is spreading rampantly.

Outside the Washington media bubble, governors say she deserves praise for presence and persistence. Gov. John Bel Edwards of Louisiana, a Democrat, said Dr. Birx “knows what’s happening in Louisiana in real time in terms of our tests results, our positivity numbers.” Gov. Tate Reeves of Mississippi, a Republican, said she prodded him for weeks to institute a statewide mask order; this week, he relented.

Global Roundup

Vietnam’s latest outbreak is more infectious than its last, officials say.

The latest coronavirus outbreak in Vietnam, which followed more than three months with no confirmed cases of local transmission, is driven by a variant of the coronavirus that is far more infectious than the variants that previously circulated in the country, health officials said.

Scientists have urged caution in concluding that a variant of the virus is more infectious. While some believe a mutation circulating widely since February gave it a biological edge, others believe more evidence is needed to differentiate any potential effect from other factors like lockdowns, travel patterns and luck.

Vietnamese officials pointed to the fast spread of the country’s most recent outbreak. It had gone months without a single death from the coronavirus, and its fast, firm reaction to the virus was praised for keeping infections in check. But an outbreak that appears to have originated in the central city of Danang last month has sent the virus to other regions.

On Friday, health officials announced that new cases had been found in two more provinces and that about 300 infections were tied to the Danang outbreak.

Research by the Vietnamese C.D.C. and a local medical research institute found that while the viral mutation detected in Danang did not lead to more severe disease, it was more infectious. Each person could spread the new variant to five or six people, rather than one or two people with earlier variants, Nguyen Thanh Long, the acting health minister, said at a government meeting.

Some research has suggested that a variant of the virus may infect more people. But the size of any effect is unknown, and other researchers have argued that current evidence is insufficient to make such a claim.

Vietnam has now recorded 10 deaths from the coronavirus, although the total caseload remains below 900. Domestic tourists who visited Danang are undergoing mass testing, and Danang officials plan to test every city resident for the virus.

In other news from around the world:

• The health ministry in India, where more than 41,000 coronavirus patients have died, said that the national caseload has topped two million.

• South Korea’s Health Ministry said the country would lift a ban on travelers from the central Chinese province of Hubei, the first epicenter of the pandemic, starting on Monday.

• Fifty million face masks that Britain bought for the National Health Service in April will not be used because of safety concerns, the BBC reported on Thursday. The masks, which were bought as part of a 252 million-pound ($ 332 million) contract, use ear loop fastenings instead of head loop fastenings. The government found that they did not fit tightly enough, according to legal documents seen by the BBC.

• About 71 percent of eligible voters cast their ballots in Sri Lanka’s election this week, a drop of only 5 percent from the parliamentary polls of 2015, the Election Commission said. The high turnout is testament to the government’s apparent success in containing the virus: Only 11 deaths have been reported in the island nation of about 21.5 million people.

• Italy threatened to suspend Ryanair flights, saying the low-cost Irish carrier has repeatedly violated safety measures imposed by the government to contain the coronavirus. In an email, the company called the accusations by the Italian authority “factually incorrect,” and said it fully complied with the measures set out by the Italian government.

• France and Germany have each recorded a higher number of daily new coronavirus cases this week than either country has seen in months. France reported 1,695 new cases on Wednesday, and Germany on Thursday reported more than 1,000. In France, the 1,242 daily average of cases since the beginning of August has almost reached the level of infections in the first week of May, when the country was still under lockdown.

Trump signs an executive order to encourage American manufacturing of critical health care supplies.

Mr. Trump signed on Thursday a long-awaited executive order that would require the federal government to purchase certain pharmaceuticals and medical supplies and equipment from American factories, in an effort to encourage more domestic manufacturing of critical health care products.

The move comes as politicians of both parties have begun criticizing the country’s dependence on China and other nations for drugs and medical supplies. The pandemic has strained supply chains and led to spiraling global demand and shortages of products like masks, testing equipment and certain pharmaceuticals.

The order, which was led by White House Trade Adviser Peter Navarro and reported by The New York Times in March, has been on hold for months amid opposition from pharmaceutical lobbyists, business groups and economists, who argued that the rule change could further disrupt supply chains and result in higher drug prices.

It will require the federal government, including the departments of defense, veterans affairs and health and human services, to purchase drugs from American sources, though it also allows certain exemptions based on cost, availability and public interest.

“If we’ve learned anything from the China virus pandemic, it is simply that we’re dangerously overdependent on foreign nations for our essential medicines, for medical supplies like masks, gloves, goggles, and the like, and medical equipment like ventilators,” Mr. Navarro said Thursday. “We are dangerously dependent, at this point in time, for essential medicines.”

But it remains unclear just how broad its effects will be, since the order gives the Food and Drug Administration the authority to decide which medicines and supplies will be subject to the new requirements, Mr. Navarro said in a call with reporters.

‘The photo does not look good’: Images of a Georgia high school’s crowded halls draw widespread attention.

The widely circulated photo from North Paulding High School in Dallas, Ga., showed students crowded into a packed hallway on their first day back to classes since the coronavirus outbreak shuttered school buildings across the country in the spring. Few were wearing masks, and there was little sign of social distancing. Then on Day 2, there was another.

The photos, which were shared on social media and cited in news reports, have quickly come to symbolize a chaotic first week back in U.S. classrooms. Schools in states where students have returned, including Georgia, Mississippi, Tennessee and Indiana, have had to initiate quarantines and in some cases shut down classrooms and entire schools temporarily become positive cases emerged.

A 15-year-old student at North Paulding, Hannah Watters, was suspended for five days for posting images of the crowded hallways on Twitter, according to her mother, Lynne Watters, who said she filed a grievance with the school on Thursday morning. North Paulding’s principal, Gabe Carmona, could not immediately be reached for comment.

The superintendent of the Paulding County School District, Brian Otott, defended his system’s reopening plan after the hallway photos circulated, saying in a letter to the community that they were taken out of context. Students only remained in the hallways briefly while switching classes, he wrote, and the school was following recommendations issued by the Georgia Department of Education.

But he acknowledged, “There is no question that the photo does not look good.”

Masks are not required at the school, Mr. Otott said, but the administration strongly encourages them for students and staff members.

“Wearing a mask is a personal choice, and there is no practical way to enforce a mandate to wear them,” he wrote, adding that more than 2,000 students attend the high school.

The school district did not respond to requests for comment on Thursday.

The district’s guidelines say staff members will do their best to require students to maintain social distancing, but note that it would “not be possible to enforce social distancing in classrooms or on school buses unless it is a class or a bus with fewer students.”

The high school opened for the school year on Monday even though there had already been reports of a coronavirus outbreak among members of the football team.

China’s offer to help with virus testing alarms Hong Kong.

The offer was presented as a favor to Hong Kong, a city struggling with a surge in coronavirus infections: a team of 60 medical officials from mainland China who would help expand testing across the city.

But it is being viewed with skepticism by some residents, who worry about the growing reach of the Chinese Communist Party and the testing project’s potential implications for their privacy.

Hong Kong could use the help. The largest wave of coronavirus infections to hit the semiautonomous city has overwhelmed its isolation wards and testing facilities in recent weeks.

The ability to provide testing for all who need or want it is a challenge for many cities and countries. That is where China comes in.

“If you want to have a quantum jump in terms of the number of tests done per day, then we definitely need some help from other countries, or the mainland government,” said Leo Poon, head of the division of public health laboratory sciences at the University of Hong Kong.

When it comes to conducting widespread testing, China is in a league of its own. The Chinese government takes pride in its ability to marshal the resources needed for mass testing.

Beijing dispatched seven medical experts to Hong Kong on Sunday to help with testing, Chinese state media reported. Yu Dewen, a health official from the southern province of Guangdong who is in charge of the team, said that even with the help of third-party laboratories, Hong Kong could only process 20,000 to 30,000 tests a day, according to Southern Metropolis Daily, a state-run Chinese newspaper. He said the team’s goal was roughly 200,000 samples a day.

But for some residents, the prospect of more readily available tests was overshadowed by concern that the outreach by Beijing was only the Communist Party’s latest intrusion into their lives.

They found it especially unnerving in the wake of the sweeping national security law that Beijing imposed on June 30 to quash dissent in Hong Kong. Police officers investigating alleged subversion crimes under the new law have been collecting DNA samples from people arrested at protests.

Carrie Lam, Hong Kong’s pro-Beijing leader, announced plans on Friday to roll out free and voluntary tests for every resident with help from the Chinese government in two weeks.

Mrs. Lam stressed that people’s personal data will be protected, and that the labs will not be given any personal information behind the specimens. But she did not provide specific details on Friday about the nature of the universal testing program, which could cover millions of residents.

Trump speculates about a vaccine around Election Day. Experts have predicted a later timeline.

As companies and researchers rush to develop a coronavirus vaccine — with some positive signs — there is growing concern that Mr. Trump’s continued efforts to tie the timing of a vaccine to the election could put undue pressure on the regulatory approval process. And in an interview with Geraldo Rivera on Thursday, the president made his most explicit remarks yet connecting the timing to the political calendar.

“Sooner than the end of the year, could be much sooner,” Mr. Trump told Mr. Rivera, a radio host, on his program on Thursday morning. When Mr. Rivera asked, “Sooner than November 3?” Mr. Trump replied, “I think in some cases, yes, possible before, but right around that time.”

Such an optimistic picture isn’t backed by public health experts. The most hopeful companies have said that if vaccine development is able to hit certain criteria, then the end of the year or the beginning of 2021 is the earliest likely time one could arrive.

Later on Thursday, as he left the White House for a trip to Ohio, Mr. Trump was asked if a vaccine before Nov. 3 would help him in his re-election bid. “It wouldn’t hurt,” he replied.

And the head of the World Health Organization urged against “vaccine nationalism” on Thursday, calling for political leaders to band together to ensure that an effective coronavirus vaccine is distributed as a “global public product.”

In an interview with Lester Holt, the “NBC Nightly News” anchor, the W.H.O.’s director-general, Tedros Adhanom Ghebreyesus, said that recovery from the coronavirus pandemic will be stalled unless countries decide to share resources to prevent the spread of the virus. “Part of the world or a few countries cannot be a safe haven,” he said. “They should recover with the rest of the world.”

In a global news briefing with reporters the same day, the director-general offered both encouragement and caution on potential vaccines. “There are many vaccines under trial, many of them in final stages, so there is hope there,” Dr. Ghebreyesus said. The pace of development was faster now than ever, he added.

Even asymptomatic people carry the virus in high amounts, a South Korean study finds.

A new study in South Korea, published Thursday in JAMA Internal Medicine, offers more definitive proof that people without symptoms carry just as much virus in their nose, throat and lungs as those with symptoms, and for almost as long.

Discussions about asymptomatic spread have been dogged by confusion about people who are “pre-symptomatic” — meaning they eventually become visibly ill — versus the truly asymptomatic, who appear healthy throughout the course of their infection.

The new study is among the first to clearly distinguish between these two groups. It measured the virus’s genetic material in the patients; the researchers did not follow the chain of transmission or grow live virus, which might have more directly confirmed active infections.

Still, experts said the results strongly suggest that asymptomatic people are unwitting broadcasters of the virus.

The South Korean team analyzed samples taken between March 6 and March 26 from 193 symptomatic and 110 asymptomatic people isolated at a community treatment center. Of the initially asymptomatic patients, 89 — roughly 30 percent of the total — appeared healthy throughout, while 21 developed symptoms.

The participants in the new study were all isolated when they tested positive for the virus and did not have the opportunity to infect others. Doctors and nurses tracked their temperatures and other symptoms, and tested their sputum — which indicates virus present in the lungs — as well as their noses and throats.

The participants were mostly young, with a median age of just 25. (A study last week found that children, who are mostly mildly infected, also harbor at least as much virus as adults do.)

The study’s estimate that 30 percent of infected people never develop symptoms is in line with findings from other studies. In an television interview on Wednesday, Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases, tendered 40 percent as the figure.

The State Department ends a blanket warning against travel abroad, but some countries still bar Americans.

The State Department on Thursday lifted its travel advisory warning U.S. citizens against all international travel during the pandemic.

Department officials said that its blanket advisory would end after four and a half months because health conditions were improving in some countries and potentially deteriorating in others. They also said that the department would revert to its practice of issuing advisories on a country-by-country basis.

As of Thursday, more than 50 countries — including Brazil, India and Russia — still carried a “level four” advisory, the State Department’s most severe warning.

Travel advisories for the United Kingdom, Spain, France, Italy and other countries have been downgraded to level three, which urges residents to “reconsider travel.”

But while the State Department changed its warnings on travel abroad, many countries — including those in the European Union — still have rules barring travelers from the United States.

Department officials recommend that people wishing to travel abroad consult the department’s travel advisory list for their destination.

A new survey found that half of Americans who flew in the past year are not ready to do so again. In the survey of nearly 6,500 travelers conducted by Gallup and the financial firm Franklin Templeton, 52 percent said they were uncomfortable flying.

Younger adults were more willing to travel; only a third of those between the ages of 18 and 34 expressed discomfort with the idea. But older adults, who tend to have more time and money to travel, were far more reluctant. Among those 55 or older, 69 percent said they would not be comfortable taking a flight.

The C.D.C. to Americans: Please do not drink hand sanitizer.

Federal health authorities issued a formal warning this week about the dangers of drinking hand sanitizer and alerted poison control centers across the United States to be on the lookout for cases of methanol toxicity after four people died and nearly a dozen became ill.

“Alcohol-based hand sanitizer products should never be ingested,” the Centers for Disease Control and Prevention said on Wednesday in an advisory.

From May 1 to June 30, 15 people in Arizona and New Mexico were treated for poisoning after they swallowed alcohol-based hand sanitizer, the agency said, adding that it was not immediately clear if any of the people who were poisoned drank the hand sanitizer for its disinfectant properties. Some adults had consumed it for its alcohol content.

Similar warnings were issued in April after Mr. Trump suggested digesting disinfectants could help fight the virus.

Hand sanitizer has become a ubiquitous and often in-demand substitute for hand washing during the pandemic. The C.D.C. has recommended the use of ethyl alcohol- or isopropyl alcohol-based hand sanitizer if soap and water are not readily available.

Last week, the Food and Drug Administration, which regulates hand sanitizers, announced that it had placed methanol-based products manufactured in Mexico on an import alert because of their toxicity. It also said it was working with retailers to recall that type of hand sanitizer and remove those products from marketplaces.

And with a round of new warnings, the agency’s list of hand sanitizers that consumers should avoid grew to 115 products. Some were cautioned against because of methanol content, others because of manufacturing processes or low levels of ethyl alcohol.

A majority of travelers are not willing to get on planes, a new survey shows.

More than half of Americans who flew in the past year are not ready to do so again, according to a new survey, underscoring the difficulty airlines face in convincing people it is safe for them to get back on planes.

In the survey of nearly 6,500 travelers conducted by Gallup and the financial firm Franklin Templeton, 52 percent said they were uncomfortable flying.

Younger adults are more willing to travel; only a third of those between the ages of 18 and 34 expressed discomfort with the idea. But older adults, who tend to have more time and money to travel, are far more reluctant. Among those 55 or older, 69 percent said they would not be comfortable taking a flight.

Unsurprisingly, views on flying vary significantly by political identification. Nearly 60 percent of Democrats said they were uncomfortable flying, compared with 54 percent of independents and just 42 percent of Republicans.

Even those willing to fly have limits. Although 44 percent said they were comfortable getting on a flight that lasted less than two hours, only 21 percent said they were open to the idea of flying more than six hours, confirming the industry consensus that international travel will take much longer to recover than shorter, domestic trips.

Travelers are also divided in their willingness to pay to have an empty seat next to them. Just under half said they would not shell out any money for greater distance from others, while 47 percent said they would pay up to $ 100. That share shrinks as the price of an empty seat rises, though 18 percent said they would spend $ 250 or more.

Another 1.2 million people in the U.S. sought jobless benefits last week.

Nearly 1.2 million workers in the United States filed new claims for state unemployment benefits last week, the government reported on Thursday. It was the lowest weekly total since March, but the nation still topped the extraordinarily high number of one million for 20 straight weeks.

An additional 656,000 claims were filed by freelancers, part-time workers and others who do not qualify for regular state jobless aid but are eligible for benefits under a separate federal program, the Labor Department said. Unlike the state figures, that number is not seasonally adjusted.

The number of new claims is down from the stratospheric levels of the pandemic’s early days, but signals the continued damage that the pandemic has inflicted on the American economy.

“There is a resurgence of Covid cases around the country that is tempering economic activity and employment gains,” said Kathy Bostjancic, chief U.S. financial economist at Oxford Economics.

And now that emergency federal benefits have expired, the unemployed will not be receiving the $ 600-a-week supplement that helped them pay bills through the spring and early summer.

Mass infection at a retirement home came through the ventilation system, a Dutch report finds.

A leaked report by the Dutch National Institute for Public Health and the Environment seems to support the theory that the coronavirus can be transmitted through the air. The case, in Maassluis, in the western Netherlands, is one the clearest examples of a warning by 239 experts that the virus is airborne.

The report, published on Wednesday by the Dutch newspaper De Volkskrant and 1Vandaag, a current-affairs show, focused on a retirement home where in June almost an entire ward of patients was infected.

Despite wearing face masks continuously except for lunch breaks, 18 staff members were also infected. When a newly installed air-ventilation system was inspected, the health authorities found large quantities of the virus on the mesh covering air intake and extraction units and in its filters.

“There is simply no other explanation possible, this is how everybody there got infected, all at the same time, through aerosols,” said Maurice de Hond, a data specialist who has long criticized the Dutch health authorities for ignoring spread through aerosols. “We need to realize this before autumn comes and more people will gather indoors.”

It is unclear why the Dutch National Institute for Public Health and the Environment has kept its findings secret, but it did tacitly adjust the guidelines for ventilation, according to De Volkskrant. Three days after the report was released internally, the organization started publicly advising to “avoid recirculation of air in spaces where several people are present, and refresh the air as often as possible.”

Reporting was contributed by Maria Abi-Habib, Geneva Abdul, Hannah Beech, Emily Bobrow, Keith Bradsher, Luke Broadwater, Emma Bubola, Julia Calderone, Benedict Carey, Niraj Chokshi, Emily Cochrane, Patricia Cohen, Melissa Eddy, Thomas Erdbrink, Jacey Fortin, Sheera Frenkel, Maggie Haberman, Mike Ives, Cecilia Kang, Annie Karni, David Leonhardt, Patrick J. Lyons, Tiffany May, Giulia McDonnell Nieto del Rio, Constant Méheut, Sarah Mervosh, Saw Nang, Richard C. Paddock, Eileen Sullivan, Jim Tankersley, Pranshu Verma, Neil Vigdor, Sui-Lee Wee, Katherine J. Wu, Ceylan Yeginsu, Elaine Yu and Karen Zraick.