BEIRUT — As many parts of the world, including the United States, explore ways to ease lockdowns aimed at containing the spread of the coronavirus, countries that had already opened up are closing down again after renewed spikes in infections.
Such a resurgence of cases had been widely predicted by experts, but these increasing numbers come as a sobering reminder of the challenges ahead as countries chafing under the social and economic burdens of keeping their citizens indoors weigh the pros and cons of allowing people to move around again.
Lebanon on Tuesday became the latest country to reimpose restrictions after experiencing a surge of infections, almost exactly two weeks after it appeared to have contained the spread of the virus and began easing up. Authorities ordered a four-day, near-complete lockdown to allow officials time to assess the rise in numbers.
The reemergence of coronavirus cases in many parts of Asia is also prompting a return to closures in places that had claimed success in battling the disease or appeared to have eradicated it altogether, including South Korea, regarded as one of the continent's top success stories.
South Korea last week rescinded a go-ahead for bars and clubs to reopen after a spike in cases, hours after officials announced the lifting of previous social distancing restrictions and the start of a "new everyday life with the coronavirus."
South Korean President Moon Jae-in warned his country Sunday to "brace for the pandemic's second wave," calling the battle against COVID-19 a "prolonged" war.
In the Chinese city of Wuhan, where the pandemic first emerged, authorities on Tuesday ordered the testing of all 11 million inhabitants after a cluster of six new infections emerged, five weeks after the city had apparently rid itself of the disease.
Germany, which is widely regarded as the model in Europe of a balanced coronavirus response, is warning that some areas may have to reinstate restrictions after localized outbreaks caused a rise in cases.
"We always have to be aware that we are still at the beginning of the pandemic," German Chancellor Angela Merkel cautioned last week as a cluster of new cases in a meatpacking plant raised fears of an intensified outbreak. "And there's still a long way in dealing with this virus in front of us."
Some countries are going ahead with plans to lift restrictions despite evidence that cases are on the rise and the disease is far from being contained. India and Russia eased their restrictions on Tuesday even as the number of infections in both countries continued to soar. France experienced a spike on Monday, the same day that the country eased its lockdowns, with 263 new cases reported, compared to 70 the previous day.
Iran, the epicenter of the disease in the Middle East, with more than 110,000 reported cases, has ordered a county in the southwestern province of Khuzestan to reimpose a lockdown after cases spiked there. But the government is still planning to proceed with the reopening of schools later this week, despite a marked jump in new infections since restrictions were eased in late April.
The new spikes underscore the question of when — or whether — it will ever be safe for coronavirus-stricken countries to lift their lockdowns.
The latest cluster in Wuhan demonstrates how hard it will be to measure whether any location is truly free of coronavirus. The new cases there suggest the coronavirus can flare up in patients up to 50 days after they have apparently recovered, said Wu Zunyou, chief epidemiologist at the Chinese Center for Disease Control and Prevention, in an interview with state broadcaster CCTV.
"The course of disease could last 30 to 50 days for some patients," Wu said. "The virus could take longer to manifest itself in patients with weak immunity, who are also prone to 'ons' and 'offs' of symptoms."
He sought to reassure citizens that the new cases did not represent a new wave of the pandemic.
"There will not be a new minor peak," Wu said. "We have had the epidemic under control after more than three months of efforts and accumulated considerable experience in both diagnosis and [epidemic] notification. Therefore, we will not allow scattered cases to develop into massive outbreaks."
Firass Abiad, who oversees coronavirus efforts at the Rafik Hariri University Hospital in Beirut, Lebanon's main government hospital, said a country's success will depend less on how it curtails the spread of disease during a lockdown than on how the country manages the inevitable resurgence after lockdowns end.
"A lockdown is a means and not an end," he said. "It's a means either to allow you to regain control or put measures in place to control coronavirus when it comes back. When we eased the lockdown, we knew there would be an increase in the number of cases."
Lebanese government officials said the lockdown was being reimposed for four days starting at midnight on Wednesday to allow the authorities time to conduct contact tracing and isolation for several new clusters that have broken out in different parts of the country. They represent 104 cases in the past four days, a big jump in a small country after infections had stabilized at the rate of one or two new cases a day.
Most are linked to some of the thousands of Lebanese who have been repatriated in recent weeks from around the world, said Souha Kanj, who heads the infectious diseases department at the American University of Beirut.
All the returnees are tested for COVID-19 and required to quarantine for two weeks even if they are negative. But some have not been adhering to the requirement, she said, citing the case of a man who returned from Nigeria and then held a party for his relatives, infecting at least 10 of them. One was a member of the security forces, who has in turn infected a dozen or so of his colleagues.
There may also be cases of renewed local transmission, perhaps stemming from people who were asymptomatic but have been silently spreading the disease, said Abiad. Lebanese released from nearly six weeks of lockdown last month have surged onto the streets, openly defying some of the continued restrictions and social distancing rules that remain in force.
Similar scenes have occurred in other countries that are ending closures. Crowds of Parisians gathered on the banks of the Seine River to toast their release on Monday from six weeks of one of the world's toughest confinements, prompting police on Tuesday to ban the consumption of alcohol in the vicinity of the river.
"In any country where people don't adhere to social distancing this is going to happen. You are going to have a surge in cases for sure," said Kanj.
Morris reported from Berlin. The Washington Post’s Min Joo Kim and Gerry Shih in Seoul and Suzan Haidamous in Washington also contributed to this report.