Coronavirus Updates: Latest News and Analysis

China temporarily halts some imports of Tyson Foods poultry.

As Beijing struggles to stop a coronavirus outbreak that appears to have started at a vast wholesale food market in the city this month, China’s customs agency is taking aim at a U.S. company in a politically contentious industry: Tyson Foods.

China’s General Administration of Customs said on Sunday that effective immediately, it was temporarily suspending poultry imports from a Tyson Foods slaughterhouse that has had coronavirus cases among its workers. Shipments from the slaughterhouse that have already arrived in China will also be seized, the customs agency said in a public notice.

The agency’s notice did not identify the location of the slaughterhouse, providing instead a registration number: P5842. Over the course of this spring, Tyson Foods has disclosed cases among its workers in several U.S. states.

On Friday, the company said that 13 percent of the 3,748 employees at its facilities in northwestern Arkansas had tested positive for the coronavirus. Almost all were asymptomatic.

Safety limits on food imports from the United States could make it even harder for China to meet its promise to buy more U.S. goods as part of its Phase 1 trade agreement with the Trump administration that was signed in January. But American critics of food processing giants, particularly pork producers, contend that the companies have risked the health of their workers by keeping operations running, in part to supply China.

Scientists have said that the coronavirus appears to spread mostly through the air, not contaminated meat. But China has already curbed almost all transmission of the virus within its own borders and is looking to stamp out even low probability risks.

A person answering the phones at the customs agency on Sunday said that it was closed for the weekend, and Tyson Foods issued no immediate comment.

In his first rally in months, President Trump bragged this weekend about his response to the pandemic, despite widespread criticism of his administration’s faltering management of the crisis.

Addressing a mostly maskless crowd on Saturday night in a sparsely filled 19,000-seat indoor arena in Tulsa, Okla., Mr. Trump mocked the coronavirus, which has killed 121,000 Americans, and claimed that he wanted to slow down testing.

Mr. Trump said the low turnout had resulted from news media reports on local officials’ health concerns about the indoor rally, and campaign advisers claimed that their supporters had trouble entering the arena because of protesters.

In reality, there were few protests across the city, and black leaders in Tulsa had made calls earlier for people to stay away.

Concerns that the event could spread the coronavirus were amplified hours before Mr. Trump took the stage when his campaign acknowledged that six staff members working on the rally had tested positive.

The campaign stressed that all rally attendees were receiving temperature checks before going through security and were then given wristbands, face masks and hand sanitizer.

Yet Trump supporters gathered in Tulsa appeared less worried about the virus and more exuberant over the president’s return to the campaign trail.

“If it is God’s will that I get coronavirus, that is the will of the Almighty,” said Robert Montanelli, a resident of a Tulsa suburb. “I will not live in fear.”

With about 100 flights expected to arrive in Spain on Sunday from across Europe’s free-travel zone — the first time international visitors have been allowed into the country’s mainland since a three-month state of emergency was lifted at midnight — hundreds of additional health officials were stationed at Spanish airports to help monitor passengers.

The first flights landing in Madrid were from Paris and Milan. Passengers were required to have their temperatures taken, fill out a safety form and undergo a visual check by an airport health official.

Although about 600 additional health officials were dispatched for the efforts, the effectiveness of the safety measures in a country that has experienced one of Europe’s worst coronavirus outbreaks was a matter of contention in political circles.

The country’s transportation and health ministers both visited Madrid’s airport on Saturday to check its safety protocol, and Transportation Minister José Luis Ábalos told a news conference that it was important to send the message that Madrid was an “open but safe city.”

But on Sunday, Ignacio Aguado, the deputy head of Madrid’s regional government, ridiculed the safety checks at Madrid’s airport, describing them on Twitter as “a joke.”

Even in an economic crisis, Japan’s workers have escaped mass layoffs.

The pandemic has devastated economies around the globe, shutting businesses and slowing spending. But unlike in the United States, where the jobless rate has soared, workers in Japan have weathered the pandemic with striking success, staying employed in large numbers.

Pro-labor attitudes in Japan, reinforced by strong legal precedents, make it uniquely difficult for Japanese companies, except under severe strain, to fire workers. And a constellation of social and demographic factors, including Japan’s aging population and shrinking work force, have allowed workers to largely hold on to their jobs and benefits, even as the economy has taken big hits over all.

Output in Japan shrank 2.2 percent in the first three months of the year, pushing the country into a recession. Data from April suggests that conditions will most likely continue to worsen.

Yet the unemployment rate in Japan has ticked up just two-tenths of a percentage point since February, to 2.6 percent. And that has helped Japan largely avoid the sense of anxiety that people in other countries experienced as companies shed employees, leaving millions without benefits in the middle of a public health crisis.

After several Major League Baseball teams reported positive coronavirus tests for players and staff members, the Yankees and Mets decided to move their preseason training from Florida, where cases have been spiking, to their home stadiums in New York, Gov. Andrew M. Cuomo said this weekend.

The announcement came soon after M.L.B. temporarily closed all of its spring training facilities, which are in Florida and Arizona, for deep cleanings and asked people to be tested for the virus before returning.

Five teams — the Philadelphia Phillies, Los Angeles Angels, San Francisco Giants, Toronto Blue Jays and Houston Astros — have confirmed that players, other employees or people connected to them have tested positive or exhibited symptoms of Covid-19.

M.L.B. suspended its spring training on March 12 and indefinitely postponed the start of the regular season. But as the league and its players’ union recently appeared to make progress in talks over returning to the field — with the regular season possibly starting in July — some players returned to the training facilities for limited, voluntary workouts.

The Yankees’ spring training facility is in Tampa, Fla., and the Mets’ is in Port St. Lucie.

While Florida reported a record number of new cases three days in a row, including 4,049 on Saturday, the number of new cases in New York has tapered off since a peak in April.

Mr. Cuomo said Mets players would begin training this week at Citi Field in Queens. It was unclear when the Yankees would arrive at Yankee Stadium in the Bronx, but the team confirmed that the stadium would become its preseason training site.

Recent reports of new coronavirus cases among athletes have heightened concerns about the resumption of competition. On Friday, just over a week after the PGA Tour restarted, the golfer Nick Watney withdrew from the RBC Heritage tournament in South Carolina after testing positive.

Rest assured, France’s culture minister says: The kiss has not been banished from movies.

As movie and television shoots in the country have slowly resumed after months of lockdown, actors have been working out ways of safely smooching, said the minister, Franck Riester.

“Kissing has started again, if I may say so, on movie sets,” he told RTL radio on Friday, although he did not refer to any specific films or actors. “Some artists got tested, waited a bit and then did that kiss that is so important in cinema.”

Last month, the agency that oversees health and hygiene conditions on French film sets issued a guide on how to keep the virus at bay, including measures for scenes that require physical intimacy.

They included adapting or rewriting the action, postponing filming, or asking actors to get tested or regularly take their temperature. Wearing masks was also recommended, camera angles permitting.

The government has created a fund of 50 million euros (about $56 million) to help producers who have to cancel a film shoot for coronavirus-related reasons, but some worry that insurers will balk at the slightest deviation from the guidelines.

Marina Foïs, an actress, expressed worry on French television last week that insurers would have undo influence over how films are made during the pandemic.

“If I want to act well, I need to abandon something,” she told France 5. “I need to let happen what will happen.”

Some U.S. states break records for new cases, many of them among the young.

With cases rising in 19 states across the South, West and Midwest in the United States, at least two states announced record-breaking numbers of new cases this weekend while infection levels reached new highs in at least two others.

Florida and South Carolina both had their third straight day breaking single-day records for news cases, while infection levels for Missouri and Nevada soared — increases that came as the United States reported more than 30,000 new infections on Friday, its highest total since May 1.

Florida reported 4,049 new cases on Saturday, bringing the state’s total to about 94,000 cases and more than 3,000 deaths. And South Carolina broke its record with 1,155 new cases.

Strikingly, the new infections have skewed younger, with more people in their 20s and 30s testing positive, Gov. Ron DeSantis of Florida said — clusters that may be especially worrying to colleges and universities that plan to bring students back to campus in the fall, when the coronavirus and the flu virus are expected to be circulating simultaneously.

In Florida — which “has all the makings of the next large epicenter,” according to model projections by the PolicyLab at Children’s Hospital of Philadelphia — an advisory from the state’s Department of Health this weekend recommended that people avoid crowds larger than 50 people. It also encouraged social distancing and mask wearing at smaller gatherings.

President Trump is set to deliver his national convention speech on Aug. 27 in Jacksonville, Fla., inside an arena that holds 15,000 people.

Two clinical trials for hydroxychloroquine, the drug President Trump promoted, are halted.

The National Institutes of Health said this weekend that it had stopped two clinical trials of hydroxychloroquine, the antimalarial drug that President Trump has promoted to treat the coronavirus with scant evidence of its efficacy.

One trial, which had enrolled close to 500 patients, ended because the drug was unlikely to be effective. The other did not have enough patients enrolled. Both are the latest indications that scientists are increasingly concluding that the drug’s promise has fallen far short of early expectations.

“In effect, the drug didn’t work,” Dr. William Schaffner, a professor of infectious diseases at Vanderbilt University Medical Center, said of the first trial.

Mr. Trump had called the drug a “game changer” and said he had been taking it. And the medical community had been closely watching the trial, because it was federally funded, placebo-controlled and run by respected investigators.

But Dr. Schaffner said, “I think we can put this drug aside and now devote our attention to other potential treatments.”

The initial trial, which was being run by the National Heart, Lung and Blood Institute, a division of the N.I.H., was one of several studies that had been organized to test the drug after a series of small, poorly controlled trials showed early signs of a benefit.

Since then, several other large trials have been halted or have not shown the drug to be effective against the coronavirus.

Making difficult pandemic conversations easier.

When it’s time to invite people over or arrange a play date, would-be hosts face tough conversations with friends, neighbors and family on their standards for avoiding coronavirus infection. Here are some strategies to help.

Reporting was contributed by Anne Barnard, Keith Bradsher, Aurelien Breeden, Benedict Carey, Emily Cochrane, Ben Dooley, Amy Julia Harris, Raphael Minder, Aimee Ortiz, Sharon Otterman, Jessica Silver-Greenberg, Liam Stack, Hisako Ueno and Mark Walker.