New clusters emerge in countries praised for successful coronavirus fights.
Several nations that have been hailed for curbing the spread of the pandemic are finding that victory over the coronavirus can be elusive and fleeting — especially after they start lifting lockdowns.
Officials from the World Health Organization are urging governments and the public to maintain “extreme vigilance” while easing restrictions and that ignoring precautions would inevitably lead to more infections. Tedros Adhanom Ghebreyesus, the director-general of the W.H.O., said on Monday that only a “slow, steady lifting of lockdowns” could ease economic pains while keeping infections at bay.
In France, drinking alcohol was banned on Paris canals and riverbanks on Monday, after throngs of people were seen drinking along the Canal Saint-Martin as the country eased strict confinement rules. Germany, despite an aggressive program of testing and tracing infections, has seen an increase in cases since measures were eased last week.
Dr. Tedros said that social distancing restrictions were still the best weapons against the virus. But the W.H.O. also said on Tuesday that some treatments, in early studies, appear to be limiting the severity or length of Covid-19.
“We do have potentially positive data coming out but we need to see more data to be 100 percent confident that we can say this treatment over that one,” Margaret Harris, a spokeswoman for the W.H.O., said at a briefing, according to Reuters news agency.
Prime Minister Narendra Modi of India announced on Tuesday a more than $260 billion economic rescue package for a nation that has been relatively spared by coronavirus infections but economically devastated by the pandemic.
Mr. Modi, who made the announcement in a televised address, did not provide many details about the package, which would amount to about 10 percent of India’s G.D.P. But he said it would help all classes of business, from farmers and migrant laborers to big companies.
“It’s overdue as the economic impact on India is going to be quite severe,” said Arvind Subramanian, a former chief economic adviser to Mr. Modi.
Mr. Subramanian said that India could afford to spend the money through a combination of bond issuance, borrowing overseas and central bank spending because the country is not heavily indebted internationally. And he said India had no choice.
Mr. Modi also urged Indians to become more economically self-reliant and referred to Mohandas K. Gandhi’s self-sufficiency campaign nearly 100 years ago that boycotted British textiles.
“Who can stop us from becoming a self-reliant India?” he said.
The country has reported more than 70,000 cases and more than 2,200 deaths from the virus. India’s strict nationwide lockdown and the global turmoil from the coronavirus pandemic have hit the country’s economy hard, casting millions of very poor people out of work. Out-of-work laborers are pouring out of cities and heading back to rural villages where they hope to rely on family members to survive.
Mr. Modi said the finance ministry would announce the specifics of the relief package in the coming days.
Many Indians were listening to Mr. Modi’s speech desperate to hear if the lockdown, imposed in late March and set to expire on May 18, would be lifted. But Mr. Modi did not directly address it, instead saying that the next version of the lockdown would be governed by a different set of rules.
The coronavirus has been detected for the first time among people living in a camp for displaced people in South Sudan, and in a migrant camp in Greece’s Aegean islands, intensifying fears of a lethal outbreak among some of the world’s most vulnerable people.
Public health officials have long warned that camps for people who have fled war and privation are ideal settings for the virus to spread fast — they are crowded, and often lacking in food, sanitation and medical resources.
The United Nations said that two people tested positive on Monday in a camp in Juba, the capital of South Sudan, where two camps house about 29,600 of the roughly 4 million people who have been displaced by a brutal civil war.
“This community is an extension of the communities around them in Juba city where we know that Covid-19 already exists,” said David Shearer, head of the United Nations mission there.
South Sudan is a poor nation with a fragile health care system, and even with help from the World Health Organization, the capacity to test for and treat the infection is very limited. Officially, the country has recorded 174 cases, but the real figure is thought to be far higher.
Mr. Shearer said on Tuesday that his group had doubled water supplies at the camps to boost handwashing, broadcast awareness messages in multiple languages and distributed more than two months worth of food to keep people from visiting local markets.
In Greece, Migration Ministry officials confirmed two cases of Covid-19 in migrants on Lesbos, one of five Aegean islands where nearly 40,000 migrants live in camps. They arrived on Lesbos last week from Turkey, which has had a far worse outbreak than Greece.
Coronavirus infections have been found among migrants on the Greek mainland, where they live in less dire conditions.
Britain will extend until October its program to ensure that private-sector workers keep getting paid if the pandemic prevents them from working, the government said on Tuesday in a clear indication that it expects it to take several months to fully reopen the economy.
As an incentive for employers to keep people on their payrolls, the government is subsidizing the pay of millions of workers who would otherwise be furloughed, along with self-employed people who cannot work. The program covers 80 percent of each person’s wages, up to 2,500 pounds a month — almost $3,100.
The program, begun in March, was originally put in place until June, and is costing billions of pounds per month. On Tuesday, the chancellor of the Exchequer, Rishi Sunak, announced that the government will keep paying 80 percent of wages through the end of July.
The subsidy will decline after that; the level has not yet been decided, but it will be at least 50 percent, officials said. Workers will continue to receive 80 percent of their pay, meaning that employers will have to pay a portion.
Business groups and labor unions largely welcomed the extension.
Mr. Sunak’s statement came a day after the government urged those who cannot work from home to go back to factories and other workplaces if they can. But some parts of the economy not expected to restart until mid-sumer or later.
Speaking in Parliament Mr. Sunak said the government had no fear of fostering dependence on government largesse.
“People up and down this country believe in the dignity of their work, going to work, providing for their families,” he said. “It’s not their fault their business has been asked to close.”
The city of Wuhan, where the coronavirus emerged late last year, has ordered that all residents be tested in the next 10 days after six new cases were reported in one neighborhood, according to a state media report.
Wuhan, with a population of 11 million, has already tested large numbers of residents. Many employers required that their workers be tested before returning to their jobs last month. The new round of testing reinforces fears that the outbreak can re-emerge from hidden cases.
An 89-year-old man was confirmed to be infected on Saturday, the first new confirmed case in the city since early April. He was tested last week after feeling unwell. Five other cases were announced on Monday, including the man’s wife, 81, and four others who live in their neighborhood. The five are all asymptomatic.
Wuhan imposed a lockdown on Jan. 23 and only lifted it on April 8.
More than 3,800 people have died in the city, according to the official tally. China has faced questions about the accuracy of its coronavirus numbers and whether it has divulged the true extent of its outbreak.
The head of the street committee for the area with the new cluster was removed from office for poor management after the cases were reported, the state-run Xinhua news service reported.
And on Sunday, Shulan in Jilin Province declared that it was at “high risk” from the epidemic after a rash of at least 15 infections around the area that started with a woman who was reported to have no history of contact with known cases.
The health official who has overseen Israel’s pandemic response abruptly resigned on Tuesday, amid complaints of chaos in the easing of coronavirus restrictions, particularly in the reopening of public schools.
Moshe Bar-Siman-Tov, director-general of the health ministry since 2015, had already faced criticism for advocating what critics said was too aggressive a response early on. But Mr. Bar-Siman-Tov credited that stance with helping Israel to control the spread of the virus, at least so far.
“The time to take action, or to take the measures that you want to take during pandemics, is when you think it’s too early,” he said in a recent interview with The New York Times.
Now, Israel’s strategy for reopening schools, drafted by the health and education ministries, has confused parents and infuriated local officials.
The youngest and oldest children have been invited back to school, but seventh- to 10th-graders are expected next week on either a two- or three-day-a-week schedule. Children in grades four to six may be told to return only on Fridays — or else every day, but only in the afternoons.
Haim Bibas, the mayor of Modiin-Maccabim-Reut and chairman of the Federation of Local Authorities, said of the plan’s authors: “They’ve gone crazy.”
They “forgot to talk to the client — the local authorities, the teachers, the students, the parents,” he said.
In his resignation letter to Prime Minister Benjamin Netanyahu, Mr. Bar-Siman-Tov trumpeted the country’s apparent success at containing the pandemic. Israel’s official death toll is about 30 per million people, compared to more than 240 per million in the United States.
He also warned against complacency.
“The work is not yet finished,” he wrote. “Israel bought previous time to prepare for a possible second wave of the virus, and the health system is overburdened even in normal times.”
The Kremlin’s chief spokesman, a close aide of Russian President Vladimir V. Putin, has been hospitalized with coronavirus, a state-controlled news agency reported on Tuesday.
RIA-Novosti said the spokesman, Dmitri S. Peskov, had tested positive for the coronavirus and was now in a hospital “ill with Covid-19.”
Mr. Peskov joins a growing list of senior officials and others around Mr. Putin who have caught the virus. These included his prime minister, Mikhail V. Mishustin, and the head of Moscow’s main coronavirus hospital, Denis Protsenko, who tested positive in late March shortly after escorting Mr. Putin around his wards.
The president himself has spent more than a month mostly holed up at his country residence outside Moscow, holding meetings with officials by video rather than in person. Tass news agency reported that Mr. Peskov, the sick spokesman, had not had any direct contact with Mr. Putin “for more than a month.”
Mr. Putin emerged in public briefly on Saturday, the 75th anniversary of the Red Army’s defeat of Nazi Germany, to lay a bouquet of red roses on the tomb of the unknown soldier next to the Kremlin. On Tuesday, he met in person at his country house with Igor Sechin, the head of the state-controlled oil company Rosneft.
News of the Kremlin spokesman’s hospitalization broke just a day after Mr. Putin, in a televised address citing progress against the pandemic, declared the end of a “non-working period” instituted in late March. While warning that “we have a complicated and long journey ahead,” he said that Russia was now ready to start returning slowly to normal.
But the country continued to report more new daily cases than any other except the United States on Tuesday as the easing measures came into effect.
Hospitals have also been overwhelmed by the crisis, with tragic results. Five patients died in a fire in an intensive care unit at a St. Petersburg hospital Tuesday morning, Russian news agencies reported, the second deadly fire at a hospital in the country treating coronavirus patients.
The preliminary cause: an overloaded ventilator. A coronavirus hospital also caught fire in Moscow on Saturday, killing one of the patients.
Health officials in Germany are attempting to tamp down concern over the rate of coronavirus spread in the country, after the public measure of it pushed above a crucial threshold for three days running, coinciding with a second major phase of reopening.
But officials from the Robert Koch Institute, Germany’s primary disease control agency, stressed on Tuesday that the number indicating the rate of viral spread — known as the reproduction or R factor — is an estimate that will vary from day to day, but is cause for concern only if it remains elevated for an extended period of time.
The institute held a news conference on Tuesday in an effort to dispel fears that Germany was at risk of gambling away its progress in managing the spread of the virus.
Epidemiologists carefully watch how many people, on average, an infected person spreads the virus to, but that number is highly variable, experts say.
“The number will always fluctuate and as long as it remains around 1.0, that is considered a stagnation and not an increase,” Lars Schaade, the vice president of the institute, said in a news conference on Tuesday.
If the figure is below 1.0, it suggests the number of active cases is declining; a number above 1.0 indicates cases are increasing. But the number must also be viewed in context of additional parameters, Dr. Schaade said. These include the number of and severity of cases, the availability of beds in intensive care wards and outbreaks in facilities such as nursing homes or meatpacking plants that can cause the figure to rise despite an overall decline at the national level.
Germany’s overall number of cases had been dropping steadily, but outbreaks in several facilities have caused them to go up in recent days to 170,508. Against the backdrop of lower numbers, such spikes will have a greater influence on the reproduction number, he said.
Stores across Germany were allowed to open their doors on Monday, regardless of their size, more children returned to classrooms, museums began welcoming visitors and restaurants began preparing to reopen their terraces and in some cases their doors — all under restrictions, but based on low new infections and a reproduction factor that had dropped to 0.7.
Dr. Schaade said that given how the institute calculated the reproduction number, it was too early to draw a direct correlation between the reopenings and the increase, but reminded Germans that they were still living with the virus.
“Do your part to help keep the virus under control,” Dr. Schaade said. “Stay at home as much as possible, limit contact to others and continue to stay at a distance.”
South Korean epidemiologists face a hurdle in their efforts to identify and test nearly 2,000 people who may have visited nightclubs that are the nexus of a new coronavirus outbreak. Many of the people are believed to be gay men who fear being outed in a society where prejudices against sexual and other minorities remain widespread.
A 29-year-old man tested positive for the virus last Wednesday. While investigating his potential contacts, officials learned that on May 2 he had visited three nightclubs frequented by gay people in Itaewon, a popular nightlife district in Seoul. That triggered a frantic campaign to trace and test Itaewon nightclub visitors. So far, 7,000 people have been tested, with 102 cases found among club visitors and their contacts.
The daily caseload has not exploded, as some feared it might. But it has climbed from three a week ago to 34 on Sunday, 35 on Monday and 27 on Tuesday.
Seoul’s mayor, Park Won-soon, this week offered free and anonymous tests to address the concerns that gay people might be outed. Under that policy, people can get tested by submitting their telephone numbers, but not their names. The number of people tested jumped from 3,500 on Sunday to 6,500 on Monday, Mr. Park said.
Officials collected the names and telephone numbers of 5,500 people who had visited five Itaewon nightclubs between late April and early this month. Under Covid-19 preventive measures, nightclub visitors are asked to write down their names and cellphone numbers before entering.
But nearly 2,000 people on the nightclubs’ rosters could not be reached, said Yoon Tae-ho, a senior disease-control official, on Tuesday. Officials feared that many of the names and telephone numbers might be fake. They were using credit card transaction records and cellphone location data to try to trace people who may have been in the nightclubs.
South Korea has reported a total of 10,936 Covid-19 cases, including 258 deaths.
The authorities in Britain are investigating the death of a railroad employee who died last month of Covid-19, two weeks after being spat at and coughed on by a man who claimed to be infected with the coronavirus.
The officer, Belly Mujinga, was checking train tickets on the concourse of London’s Victoria station on March 22 when a man spat and coughed on her and a colleague, telling them that he had the virus, according to the Transport Salaried Staffs’ Association, the union Ms. Mujinga belonged to.
The British Transport Police has launched an inquiry and is attempting to find the man.
It is not clear if actually had the virus, or if he transmitted it to Ms. Mujinga, but within days of the assault, she and her colleague fell ill with the virus, the union said.
On April 2, Ms. Mujinga, who had underlying respiratory problems, was taken to a hospital, where she was put on a ventilator. She died on April 5.
“There are serious questions about her death,” said Manuel Cortes, General Secretary of the union. “It wasn’t inevitable.”
Last month, Matt Hancock, the British health secretary, announced that 60,000 pounds, about $74,000, would be paid to the survivors of health and care workers who die in the pandemic. The transport staff union on Tuesday called on the government to extend compensation to the families of any essential service workers killed by Covid-19.
The central government appears to be keeping the coronavirus outbreak largely under control within China’s borders. But it has deflected or downplayed questions about its initial response to the virus, in a pattern that seems much unchanged since the 2008 quake, China’s deadliest in decades.
Twelve years ago, nearly 70,000 people died after the earthquake wrecked buildings and roads in Sichuan and sent boulders careening down mountains and hillsides. A large number of the victims were schoolchildren, raising questions about building standards and corruption in the area.
The government eventually acknowledged that a rush to build schools probably led to shoddy construction. Still, officials tried to stifle unapproved commemorations that could have rekindled uncomfortable questions about why so many people died. Official memorial ceremonies, by contrast, focused on the heroism of the rescue effort and the speed of the reconstruction.
Three months after the authorities virtually shut down China to stop the coronavirus outbreak, its workers have returned to their jobs with the aim of restarting the country’s vast growth machine without igniting another outbreak. If Chinese factories and offices can successfully restart without major infections, they could serve as a model for President Trump and other leaders who want to get their economies back on track.
Many of the new rules are obvious: Use disinfectants and masks and keep your distance from colleagues. But some call for tracking and nudging employees in ways that workers in other countries may find unacceptable, including use of government-sanctioned health tracking apps. At the same time, local authorities have set up a confusing patchwork of rules that differ from city to city.
Everyone agrees on one thing: There is no going back to life before the pandemic.
“Life will not become like it was before,” said Johann Wieland, the chief executive officer of BMW’s joint venture in China, which employs 20,500 people. “This is what we have to learn.”
Major companies are asking workers to change personal habits. Foxconn, the Taiwanese electronics giant that makes iPhone and other Western-branded gear in vast Chinese factories, has advised employees to avoid public transportation.
Shifting rules from place to place have snarled logistics and supply chains, however. While restrictions have eased since China sharply limited movement around the country earlier in the outbreak, local authorities, especially where sporadic infections have emerged, still sometimes erect temporary barriers.
To stay safe, many employers have embraced government-endorsed and newly built-in health code functions in some of China’s most popular smartphone apps like Alipay and WeChat. One of the first services built to gauge a person’s infection risk, the health code function tracks travel to see whether the user has been to areas with high infections, though the creators and the Chinese government have not disclosed full details about how it works. When prompted by health workers, police officers or security personnel, a person would display a code colored red, yellow or green.
The State Administration for Market Regulation, a business standards regulator, is creating a database of health data collected from citizens during the outbreak. But the system, which would use QR codes, is still in its early days and has already had glitches.
For much of the world, boarding a plane has been out of the question for weeks, with lockdown measures banning all but essential travel.
But as measures have eased, and patience with them has worn thin, packed planes are increasingly becoming a concern, including in Spain, one of the countries hit hardest by the pandemic.
Passengers seated on a packed Iberia Express plane on Sunday between Madrid and the island of Gran Canaria posted videos on social media of the crowded flight. Many of them filed complaints with the country’s military police which said it would investigate the airline.
While restrictions limit travel within Spain, people can get around them if they provide documentation of exceptional circumstances. And the government has left it up to airlines how operate safely.
On Tuesday, Fernando Simón, the director of Spain’s center for health emergencies, told a news conference that “distance inside the plane should be maintained,” while acknowledging that the recommendation might need clarification.
“I think it is an important debate if we are going to move progressively toward a normalization of air transport,” he said.
Spain announced on Tuesday that anyone traveling into the country would be quarantined for 14 days upon arrival. Italy already has similar quarantine rules in place, with exemptions for cross-border workers and health personnel.
Starting this week, travelers entering France from a list of countries where the virus is active also face a 14-day quarantine. The British government also announced plans to quarantine visitors who arrive from abroad.
India’s carbon dioxide emissions have dropped for the first time in four decades, reflecting the impact of an economic slowdown from the coronavirus lockdown and a broader weakening of demand for fossil fuels on the subcontinent, experts say.
Researchers at Carbon Brief, an environmental website that tracks climate and energy policy, found that the emissions fell around 15 percent in March and likely dropped another 30 percent in April.
Lower electricity consumption during a nationwide lockdown, which started in March, along with a surge in competition among renewable energy sources, has cut demand for thermal power.
Coal-fired power generation, which is linked with higher air pollution, fell 31 percent in the first three weeks of April, according to government data compiled by Carbon Brief.
The supply of energy from renewables remained relatively stable during the lockdown, rising about 6 percent in March and dropping only slightly in April.
India is one of the largest emitters of greenhouse gases on the planet. Just five years ago, the country built a series of coal-fired power plants, more than doubling its capacity and drawing ire from climate activists.
But as the cost of solar power fell, the country canceled many coal projects, with Prime Minister Narendra Modi pledging that 40 percent of India’s electricity capacity would come from non-fossil fuel sources by 2030.
As businesses open and restrictions ease in parts of the United States, scientists say a much-feared “second wave” of infection may not wait until fall and instead may become a series of wavelets breaking unpredictably across the country.
Most states that are reopening have not met even minimal criteria set by public health experts for doing so safely, and in some, coronavirus cases are rising. A resurgence in infections may not become apparent for two or three weeks, when some people would need hospitalization.
The question now, scientists say, is whether the nation can minimize the damage.
Evidence is mounting that masks — if worn in public places, by everyone — are far more effective at stopping transmission than was previously realized. While testing remains inadequate, home-use nasal swabs and saliva tests are on the way and may provide a clearer picture of where the virus is.
And scientists are also learning more about the virus.
A new study published Monday in the journal JAMA Pediatrics paints the most detailed picture yet of American children who were treated in intensive care units as the pandemic was taking hold.
The study looked at 48 cases from 14 hospitals in patients under 21, in late March and early April. Two patients died. Eighteen were placed on ventilators and two remain on the breathing machines more than a month later, said Dr. Lara S. Shekerdemian, chief of critical care at Texas Children’s Hospital, and an author of the study.
The study both reinforces the evidence that only a small percentage of children will be severely affected by the virus, but they can become devastatingly ill.
President Trump abruptly ended his Rose Garden news conference on Monday shortly after a Chinese-American reporter pressed him on why he suggested she “go ask China” in response to her question on virus death rates.
On Tuesday morning, Mr. Trump seemed to defend the action when he posted the message “Fake Journalists!” on Twitter in response to a post from one of his lawyers praising his actions.
Weijia Jiang, a White House correspondent for CBS News, asked Mr. Trump why he had created a “global competition” by claiming that the United States had done far better than any other country on testing its citizens for the virus.
“Well,” Mr. Trump responded, “they’re losing their lives everywhere in the world, and maybe that’s a question you should ask China.”
Ms. Jiang, who had been leaning into a contact-free microphone to ask her question, lowered her face mask and paused for a couple seconds before asking, “Sir, why are you saying that to me, specifically?”
In a recent interview, Mr. Trump complained that Ms. Jiang and another reporter were not behaving like Donna Reed, an actress famous for her portrayals as a consummate housewife. Mr. Trump has targeted Ms. Jiang in recent days for her tough line of questioning in news briefings, including gruffly telling her to “keep your voice down” in past exchanges.
The next reporter he called on, Kaitlan Collins of CNN, has engaged in similar back-and-forth exchanges with Mr. Trump. Ms. Collins tried to ask Mr. Trump a question after briefly ceding her turn at the microphone to let Ms. Jiang follow up, but Mr. Trump tried to move on to another reporter.
After Ms. Collins remained at the microphone and twice tried to ask her question, Mr. Trump abruptly ended his news conference and left the Rose Garden.
Reporting and research was contributed by Jeffrey Gettleman, Hari Kumar, Maria Abi-Habib, David M. Halbfinger, Ceylan Yeginsu, Andrew Higgins, Kai Schultz, Livia Albeck-Ripka, Anton Troianovski, Alexandra Stevenson, Cao Li, Keith Bradsher, Elian Peltier, Megan Specia, Choe Sang-Hun, Clifford Krauss, Raymond Zhong, Wang Yiwei, Melissa Eddy, Dan Bilefsky, Donald G. McNeil Jr., Neil Vigdor, Maggie Haberman, Michael D. Shear, Austin Ramzy, Stephen Castle, Richard Pérez-Peña, Mihir Zaveri, Raphael Minder, Elisabetta Povoledo and Aurelien Breeden.