PARIS: Plastic barriers and millions of masks appeared Monday on the streets of Europe's newly reopened cities, as France and Belgium emerged from lockdowns, the Netherlands sent children back to school and Greece and Spain further eased restrictions. All faced a delicate balance of trying to restart battered economies without fueling a second wave of coronavirus infections.

Social distancing was the order of the day but just how to do that on public transit and in schools was the big question.

With Monday's partial reopening, the French did not have to carry forms allowing them to leave their homes but crowds quickly developed at some metro stations in Paris, one of France's viral hot spots. A last-minute legal challenge emerged to the government's practice of confining people to their own regions, further confusing the post-lockdown landscape.

Antoinette van Zalinge, principal of the De Notenkraker elementary school in Amsterdam, wore a wide white skirt and a hula hoop slung from her shoulders and carried a long stick with a hand at one end so she could shake hands with students while still keeping 1.5-meters (5-foot) apart.

In Paris, hairdressers practiced their new workflow over the weekend ahead of Monday’s reopening, and planned to charge a “participation fee” for the new disposable protective gear they’ll need for each customer. Walk-in customers will be a thing of the past, said Brigitte L’Hoste, manager of the “Hair de Beauté” salon, who expects the number of appointments to be cut in half.

“The face of beauty will change, meaning clients won’t come here to relax. Clients will come because they need to," said Aurelie Bollini, a beautician at the salon. "They will come and aim at getting the maximum done in the shortest time possible.”

Roughly half of Spain's 47 million people stepped into a softer version of the country’s strict confinement, beginning to socialize, shop in small stores and enjoy outdoor seating in restaurants and bars. its biggest cities of Madrid and Barcelona remained under lockdown, however.

Fears about new waves of infection have been born out in Germany, where a new cluster was linked to a slaughterhouse; in Wuhan, the Chinese city where the virus started; and in South Korea, where a single nightclub customer was linked to 85 new infections.

The South Korean government pushed back hard against that wave, halting the school re-openings that had been planned for this week and re-imposing restrictions on nightclubs and bars. It is now trying to track 5,500 people who had visited a popular Seoul entertainment district by checking credit-card transactions, mobile-phone records and security camera footage.

In Germany, gyms re-opened in the most populous state, but authorities there and in France have said any backsliding in the daily number of infections could lead to new restrictions.

“We’re going to have to learn to live with the virus,” Health Minister Olivier Veran said on BFM television.

The hurdles ahead for tourism and the service industries were clear, even in places where infections are diminished. Shanghai Disneyland reopened to visitors, but let in limited numbers and demanded that they wear face masks and have their temperatures checked.

“We hope that today’s reopening serves as a beacon of light across the globe, providing hope and inspiration to everyone,” the president of Shanghai Disney Resort, Joe Schott, told reporters.

In the U.K. — which has the second-most coronavirus deaths in the world behind the U.S. — Prime Minister Boris Johnson announced a modest easing of the country’s lockdown but urged citizens not to surrender the progress already made. Some people, however, were confused as the government shifted its slogan from “stay home” slogan to “stay alert" and Scotland, Wales and Northern Ireland stuck with the old slogan.

People in jobs that can’t be done at home “should be actively encouraged to go to work” this week, he said. He also set a goal of June 1 to begin reopening schools and shops if the U.K. can control new infections and the rate that each patient infects others. Johnson himself is the only world leader to recover from a serious bout of COVID-19.

“We will be driven not by mere hope or economic necessity,” Johnson promised. “We’re going to be driven by the science, the data, and public health.”

In the U.S., Trump administration officials spoke optimistically about a relatively quick rebound from the pandemic — but then had to announce that Vice President Mike Pence “self-isolating” after one of his aides tested positive.

U.S. Treasury Secretary Steven Mnuchin predicted the American economy would rebound in the second half of this year from unemployment rates that rival the Great Depression. Another 3.2 million U.S. workers applied for jobless benefits last week, bringing the total over seven weeks to 33.5 million unemployed.

The U.S. has seen 1.3 million infections and nearly 80,000 deaths, the most in the world by far, according to a tally by Johns Hopkins University. Worldwide, 4 million people have been reported infected and more than 280,000 have died, over 150,000 of them in Europe. Health experts believe all those numbers understate the true toll of the pandemic for different reasons.

The director of the University of Washington institute that created a White House-endorsed coronavirus model said moves by states to reopen businesses “will translate into more cases and deaths in 10 days from now.” Dr. Christopher Murray of the Institute for Health Metrics and Evaluation said states where cases and deaths are going up more than expected include Illinois, Arizona, Florida and California.

India reported its biggest daily increase in coronavirus cases Monday as it prepared to resume train service to ease a lockdown that has hit migrant workers especially hard by eliminating the daily wages they use to feed their families. The government reported 4,213 new cases for more than 67,000 total, including 2,206 deaths.

The railway system is India’s lifeline, transporting 23 million people across the vast subcontinent each day. When service restarts Tuesday, passengers must wear masks and pass health screenings before being allowed to board and the trains will make fewer stops than usual.

While unemployed workers in developed nations are temporarily buoyed by benefits and job-protection schemes, millions elsewhere are facing dire economic prospects. In a slum on the banks of a sewage-tainted river in Lebanon, Faiqqa Homsi feels that her family being pushed closer and closer to the edge.

A mother of five, she was already struggling, relying on donations to care for a baby daughter with cancer. The coronavirus shutdown cost her husband his meager income driving a school bus and upended her hopes of earning money selling juice.

“It is all closing in our face,” Homsi said.