Covid-19 Live Updates

Around the world, education officials move on with plans despite fears and outbreaks.

As teachers and students look ahead to the start of the school year, officials around the world continued this week to roll out and refine strategies to address the challenges and fears brought on by the pandemic, while getting back to the business of learning.

The University of North Carolina at Chapel Hill announced it would shift to remote learning for all undergraduate classes starting Wednesday, a move that came after the university said it had seen a number of cases emerge.

In Los Angeles, public schools on Monday will begin a sweeping program to test hundreds of thousands of students and teachers even though, for the time being, the Los Angeles Unified School District will begin school online. The testing plan, which will be rolled out over the next few months, will seek to administer tests to nearly 700,000 students and 75,000 employees as the district, the nation’s second-largest, awaits permission from public health authorities to resume in-person instruction, said Austin Beutner, the district’s superintendent.

In New York City, Mayor Bill de Blasio has been hoping to reopen the nation’s largest school system on a part-time basis for the city’s 1.1 million schoolchildren this fall — a feat no other big-city mayor is currently even attempting. But Mr. de Blasio is facing mounting pressure from the city’s teachers, principals and even members of his own administration to delay the start of in-person instruction by at least a few weeks to give educators more time to prepare.

Principals say they need more than the two work days the city has allotted for them to meet with teachers in September in order to make decisions about staffing. About 50 school leaders signed a letter that called for a delay to in-person instruction until the end of September and included a detailed plan for how to phase children into schools over the course of the fall, starting with young children.

Belgian officials will try a different approach, with students returning to school five days a week starting Sept. 1 as officials say the benefits of in-person education outweigh the risks posed by the pandemic.

“We know the situation is still dangerous,” said Michael Devoldere, an education spokesman for the Dutch-speaking regional government. “But parts of our student population have not seen a classroom since March, and that’s not sustainable.”

But in some poor countries — and poverty-stricken areas of developed ones — access to broadband and computers is scarce or nonexistent, making online learning an impossible option. That has led to a renewed reliance on educational television, which is having a moment after years of heavy investment in internet learning.

“Ideally, one would have, like, laptops and all these super-fancy things at home,” said Raissa Fabregas, a professor of economics and public affairs at the University of Texas at Austin, who has studied educational television in Mexico. “But if you don’t have them, this is better than nothing.”

The reopening of American college campuses, meanwhile, is generating concerns about students’ cavalier attitude toward social distancing at fraternity and sorority events, bars and house parties. Video footage appearing to show University of North Georgia students attending a crowded off-campus party garnered online attention over the weekend. A spokesperson at the Dahlonega, Ga., school said that officials were “disappointed” that mostly-maskless students at the party failed to heed social distancing guidelines.

Doctors on the front lines of the pandemic say they are fighting not just the coronavirus, but also a never-ending scourge of misinformation about the disease that is hurting patients. Some say they regularly treat people more inclined to believe what they read on social media than what a medical professional tells them.

Before the pandemic, medical professionals had grown accustomed to dealing with patients misled by online information, a phenomenon they called Dr. Google. But in interviews, more than a dozen doctors and misinformation researchers in the United States and Europe said the volume related to the virus was like nothing they had seen before.

According to the doctors and researchers, several factors are to blame: leaders like President Trump who amplify fringe theories; social media platforms that are not doing enough to stamp out false information; and individuals who are too quick to believe what they see online.

For example, approximately 800 people worldwide died in the first three months of the year — and thousands more were hospitalized — after following unfounded claims online that advised ingesting highly concentrated alcohol to kill the virus, researchers concluded in a report published last week in the American Journal of Tropical Medicine and Hygiene.

The American Medical Association and other groups representing doctors say the false information spreading online is harming the public health response to the disease. The World Health Organization is developing methods to measure the harm of virus-related misinformation online, and over two weeks in July the group hosted an online conference with doctors, public health experts and internet researchers about how to address the problem.

The falsehoods, doctors say, have undermined efforts to get people to wear masks and fueled a belief that the seriousness of the disease is overblown.

At some hospitals, people have arrived asking for a doctor’s note so they do not have to wear a mask at work because they believe another online rumor — that it will harm their oxygen levels. And a growing fear is that vaccine conspiracy theories could undermine eventual vaccination efforts critical for returning to pre-pandemic routines.

Online platforms like YouTube, which is owned by Google, and Facebook have introduced policies to limit coronavirus misinformation and elevate material from trusted sources. This month, Facebook and Twitter removed a post by Mr. Trump’s re-election campaign that falsely claimed that children do not get virus.

But untrue information continues to spread. Last month, a video from a group of people calling themselves America’s Frontline Doctors conveyed inaccurate claims about the virus, including that hydroxychloroquine, an anti-malaria drug, is an effective coronavirus treatment and that masks do not slow the spread of the virus. The video was viewed millions of times.

U.S. ROUNDUP

The U.S. postmaster general will testify before a House panel next week.

Louis DeJoy, the postmaster general, has agreed to testify before a key House panel next week, as Democrats step up their scrutiny of sweeping changes at the agency.

Mr. DeJoy will voluntarily appear before the House Oversight Committee next Monday as part of the panel’s continuing investigation into whether the cost-cutting changes he has championed at the agency could impair the rights of voters to cast their ballots by mail in the November election.

Earlier in the day, Senator Mitch McConnell, Republican of Kentucky and the majority leader, pushed back on concerns that the United States Postal Service would not be able to handle as many as 80 million ballots cast by Americans by mail in the November election. He told reporters in his home state on Monday that “the Postal Service is going to be just fine.”

“We’re going to make sure that the ability to function going into the election is not adversely affected,” Mr. McConnell said at a news conference in Horse Cave, Ky.

Mr. McConnell’s comments come a day after Speaker Nancy Pelosi, of California, called the House back from its annual summer recess nearly a month early so that the chamber could vote on legislation to block changes at the Postal Service that voting rights advocates warn could disenfranchise Americans casting ballots by mail during the pandemic.

On a private caucus call with Democrats, Representative Steny H. Hoyer of Maryland, the majority leader, told lawmakers that the House is expected to vote on legislation on Saturday, according to a person familiar with the discussion.

There has been rising concern across the country over the integrity of the November election and how the Postal Service will handle as many as 80 million ballots cast by Americans who are worried about venturing to polling stations during the pandemic. Mr. Trump has repeatedly derided voting by mail as vulnerable to fraud, without evidence, and the issue had become a prominent sticking point in negotiations over the next round of virus relief.

Mail-in voters from California, Pennsylvania, Illinois, New Jersey, Wisconsin and New York filed a lawsuit Monday against Mr. Trump and Mr. DeJoy seeking to block cuts to the Postal Service ahead of the November election. The suit, filed in Federal District Court in Manhattan, asks the court to declare that Mr. Trump and Mr. DeJoy have violated voters’ rights by cutting the Postal Service in an effort to stymie mail-in voting.

In other developments around the United States:

• With the pandemic still raging, the Democratic National Convention, which begins on Monday, will be conducted almost entirely online. Wisconsin is averaging about 770 new cases per day, more than twice as many daily cases as at the start of summer, but also far fewer than the state’s late-July peak of more than 950 cases per day. Michelle Obama, the former first lady, and Senator Bernie Sanders of Vermont, the runner-up in the Democratic primary, will headline the first night. Here’s how to watch.

• Under emergency coronavirus orders, the Trump administration is using hotels across the country to hold migrant children and families, creating a largely unregulated shadow system of detention and swift expulsions.

• Mayor Carlos Gimenez of Miami-Dade County, Fla., said Monday that he has been holding near-weekly phone meetings with Mayor Francis Suarez of Miami and Drs. Jerome Adams, Deborah L. Birx and Anthony S. Fauci. The federal experts have taken a special interest in the stubborn virus spread in the region. Though the county’s positivity rate has dropped, Mr. Gimenez said the county’s rate needs to continue to fall to under 10 percent before more businesses can reopen.

A South Korean pastor whose church is at the center of a new outbreak has tested positive.

The Christian pastor accused by South Korea’s president, Moon Jae-in, of impeding the government’s effort to fight the virus tested positive on Monday, officials said.

The pastor, the Rev. Jun Kwang-hoon, leads Sarang Jeil Church in Seoul, which has become the center of the latest outbreak in South Korea, with more than 300 cases reported among its members and contacts in the past six days.

Even before his church grabbed headlines with the outbreak, Mr. Jun has been known widely in South Korea for organizing large anti-government rallies against Mr. Moon. During these rallies, the conservative pastor called for Mr. Moon’s ouster, calling the liberal president a “North Korean spy” and accusing him of trying to “communize” South Korea.

Mr. Jun’s infection was confirmed on Monday by Lee Seung-ro, the mayor of Seongbuk-gu, a district of Seoul, where Mr. Jun’s church is located. Mr. Jun was hospitalized on Monday after he tested positive, Mr. Lee said in a Facebook post.

Mr. Jun and some of his church followers attended a large anti-government rally in downtown Seoul on Saturday, ignoring government orders to isolate themselves at home amid a surge in infections among their congregation, officials said. Mr. Moon called their behavior “an unpardonable act against the safety of the people.”

Mass infections in Mr. Jun’s church and another church in Gyeonggi Province, which surrounds the capital city, have helped push the daily caseload in South Korea to three-digit figures in the past four days. South Korea reported 197 new cases on Monday.

“What we see now is believed to be an early stage of what could become a big wave of infections,” said Jung Eun-kyeong, director of the Korea Centers for Disease Control and Prevention, on Monday. “If we fail to control the spread now, the number of cases could explode exponentially.”

Health officials said on Monday that they have so far counted 319 patients linked to Mr. Jun’s Sarang Jeil Church. The outbreak is the second largest cluster reported in South Korea, following the mass infections in the Shincheonji Church of Jesus in the central city of Daegu in February and March claimed 5,200 patients.

It was not immediately clear where and how Mr. Jun contracted the virus. But his infection prompted the authorities to repeat their call on all the thousands of participants in the Saturday rally, as well as all members of Mr. Jun’s church, to report for testing.

GLOBAL ROUNDUP

New Zealand delays its election after a cluster of cases.

New Zealand said on Monday that it would postpone its national election by four weeks as a cluster of new virus cases continues to spread in Auckland, its largest city.

Prime Minister Jacinda Ardern, who has the sole authority to determine when people cast ballots, said she had consulted with all the major parties before deciding to move the election from Sept. 19 to Oct. 17. The latest possible date she could have chosen was Nov. 21.

Ms. Ardern called the new date a compromise that “provides sufficient time for parties to plan around the range of circumstances we could be campaigning under, for the electoral commission to prepare, and for voters to feel assured of a safe, accessible and critical election.”

But she ruled out further change. Even if the outbreak worsens, she said, “we will be sticking with the date we have.”

The election delay came as the mysterious cluster of new cases grew to 58 on Monday.

Health officials are still scrambling to test thousands of workers at airports and other points of entry, along with quarantine facilities and a frozen food warehouse, as they try to determine how the virus re-emerged last week after 102 days without known community transmission in the country.

In other developments around the world:

• Fearing a “twindemic” that combines a resurgence of the coronavirus and a severe flu season, health officials are encouraging people to get flu shots.

• Australia recorded its deadliest day of the pandemic, reporting 25 deaths in the previous 24 hours on Monday, all in the state of Victoria. The country has had more than 23,000 cases and more than 400 deaths, according to a Times database.

• India reported 941 deaths on Monday, taking the country’s death toll past 50,000. Last week, India overtook Britain as the country with the world’s fourth-highest number of deaths, after the United States, Brazil and Mexico.

• Thousands of people in Madrid protested on Sunday against restrictions the Spanish government implemented — including mask wearing in all indoor and outdoor spaces and an order for nightclubs to close — in response to a recent surge in cases. The leader of the Madrid’s regional government, Isabel Díaz Ayuso, on Monday said the anti-mask protests were “irresponsible,” and she called on citizens to show solidarity in the fight against the virus.

• South Africa loosened some virus-related restrictions on Monday, including lifting a ban on the sale of tobacco and alcohol and permitting travel between provinces. Restaurants and taverns were allowed to return to normal business, subject to strict hygiene regulations, and gatherings of up to 50 people were again allowed. South Africa has the world’s fifth-highest caseload, with at least 587,000 cases, according to a Times database.

• It’s lights out for discos and clubs in Italy. As infections in the country creep back up — especially among young people — the authorities are clamping down. In addition to ordering dancing establishments closed, they are requiring the outdoor use of masks from 6 p.m. to 6 a.m. in popular gathering spots. “We cannot nullify the sacrifices made in past months,” Italy’s health minister, Roberto Speranza, said on Facebook.

• Japan’s economy shrank by 7.8 percent in the second quarter of the year, posting its worst performance on record as the country reeled from the effects of the pandemic.

• Thailand’s economy, which depends heavily on tourism and exports, shrank by 12.2 percent in the second quarter, its biggest contraction since 1998, the state planning council said on Monday. Thailand barred visitors from abroad starting in early April to prevent new cases of the virus. The strategy seems to be working: The country has gone 83 days without recording a new case of community transmission.

• The Canadian Football League said Monday that it would not play a season in the fall and that it would instead focus on trying to stage a season in 2021. League officials said a lack of live fans at games would knock out its top source of revenue, and the league did not get governmental support to stage the season in a single city.

Gyms in New York can reopen with limits as soon as Aug. 24, the governor said.

Mr. Cuomo’s announcement came with several caveats: Gyms will be limited to a third of their total capacity, and people would be required to wear masks at all times. The state will also require that gyms have sign-in forms to assist with contact-tracing efforts.

Local governments will also need to inspect gyms to make sure they meet the state’s requirements before they open or within two weeks of their opening. Local governments can stop gyms from holding indoor classes, Mr. Cuomo said.

It was not immediately clear when New York City would clear gyms for reopening, or which agency would be responsible for conducting inspections or enforcing regulations.

Mitch Schwartz, a spokesman for Mayor Bill de Blasio, said that the city would develop its inspection system in the coming weeks, but that it did not plan to initially allow indoor fitness classes when gyms reopened.

Still, the decision marked a significant step forward in the state’s return to the pre-pandemic status quo, even as officials have grown concerned about another large outbreak.

Epidemiologists have also said that they believe the risk of transmission is higher indoors, which led Mr. Cuomo in June to keep gyms, as well as movie theaters, shopping malls and bowling alleys, closed. Similar concerns also led state officials to delay allowing indoor dining in New York City, even as they allowed it elsewhere in the state.

Though some businesses and trainers have tried to adapt to regulations by moving classes or sessions outside, struggling gym owners had been frustrated by the state’s decision for weeks. More than 1,500 of them joined a class-action lawsuit filed last week that aimed to force New York to allow their reopening.

New research shows that gaiters can protect just as well as other cloth masks.

Lightweight neck gaiters, a tube of fabric worn around the neck, have been popular during the pandemic with runners, cyclists and people with beards because they can be pulled up to cover the nose and the mouth and used as a mask.

But in recent days, there has been a backlash. It started after a small study from Duke University showed that a neck gaiter performed poorly when a person wearing a gaiter said the words “Stay healthy, people” five times. During that test, the scientists observed a slight increase in the number of expelled saliva particles when the person wore the gaiter than when the wearer wore nothing at all.

Although the technique the study’s authors used was not a reliable way to measure particles, and their finding was not statistically meaningful, they hypothesized that wearing a neck gaiter might cause more small droplets to spew through the fabric, not fewer.

A wave of alarmist reports on news sites and social media quickly followed. “Wearing a neck gaiter could be worse than wearing no mask at all,” read the headline in The Washington Post.

Even the study’s authors said their data had been misconstrued. “Our intent was not to say this mask doesn’t work, or never use neck gaiters,” said Martin Fischer, an associate research professor in the department of chemistry at Duke and a co-author of the study.

Researchers are trying to model herd immunity.

To achieve so-called herd immunity — the point at which the virus can no longer spread because there are not enough vulnerable humans — scientists have suggested that perhaps 70 percent of a given population must be immune, through vaccination or because they survived the infection.

Now some researchers are wrestling with a hopeful possibility. In interviews with The New York Times, more than a dozen scientists said that the threshold is likely to be much lower: just 50 percent, perhaps even less.

The new estimates result from complicated statistical modeling of the pandemic, and the models have all taken divergent approaches, yielding inconsistent estimates. It is not certain that any community in the world has enough residents now immune to the virus to resist a second wave.

But in parts of New York, London and Mumbai, for example, it is not inconceivable that there is already substantial immunity to the coronavirus, scientists said.

“I’m quite prepared to believe that there are pockets in New York City and London which have substantial immunity,” said Bill Hanage, an epidemiologist at the Harvard T.H. Chan School of Public Health. “What happens this winter will reflect that.”

The initial calculations for the herd immunity threshold assumed that each community member had the same susceptibility to the virus and mixed randomly with everyone else in the community.

“That doesn’t happen in real life,” said Dr. Saad Omer, the director of the Yale Institute for Global Health. “Herd immunity could vary from group to group, and subpopulation to subpopulation,” and even by postal codes, he said.

For party hosts, rapid testing is the new velvet rope.

Dr. Asma Rashid, who runs a members-only medical concierge service in the Hamptons, has received some of the most sought-after party invitations this summer.

“We’ve gone to these private, private, private events, where they have me sign a ‘nothing you see in this house can be leaked’ document,” she said. “This is still a party town.”

Dr. Rashid is there to administer rapid or real-time tests for coronavirus. She performs the procedure — either a finger prick or a nose swab — in the car, and then lets guests into the house only if their tests come back negative. The entire procedure takes less than 30 minutes.

While most people in the United States wait seven to 14 days for results, a privileged few have access to rapid tests. There are a few types — some detect antibodies, others antigens or viral genetic material — but they all provide an answer in under 30 minutes.

Hosts are hiring doctors to screen guests before they attend gatherings, or children coming in from out of town for sleepovers. Other people are getting tests to provide peace of mind after a particularly wild night. Event companies are offering rapid testing as a service to clients alongside catering and music. Instagram influencers are even touting the service.

Still, these rapid tests aren’t totally reliable, said Dr. Demetre Daskalakis, New York City’s deputy commissioner of disease control. “Negatives are not definitive,” he said. (And there certainly have been false positives.)

“No test is 100 percent,” Dr. Rashid said. “A negative test does not preclude one to not be carrying the virus.”

Reporting was contributed by Maggie Astor, Luke Broadwater, Ben Casselman, Damien Cave, Choe Sang-Hun, Emily Cochrane, Caitlin Dickerson, Ben Dooley, Julia Echikson, Catie Edmondson, Reid J. Epstein, Richard Fausset, Luis Ferré-Sadurní, Jacey Fortin, Oskar Garcia, Michael Gold, J. David Goodman, Astead W. Herndon, Jan Hoffman, Shawn Hubler, Alyson Krueger, Apoorva Mandavilli, Patricia Mazzei, Raphael Minder, Patrick McGeehan, Richard C. Paddock, Tara Parker-Pope, Adam Satariano, Mitch Smith, Eileen Sullivan and Tracey Tully.