Spain and Italy demanded more European help as they fight still-surging coronavirus infections amid the continent’s worst crisis since World War II. In the U.S., authorities urged millions in the hard-hit New York City region to stop traveling to keep the virus contained.

From Milan to Madrid to Michigan, medics are making tough choices about which patients to save with the limited breathing machines they have. The confirmed global death surpassed 30,000 and new virus epicenters emerged in key U.S. cities like Detroit, New Orleans and Chicago. Even rural American has not been immune, as virus hotspots erupt in Midwestern towns and in Rocky Mountain ski havens.

Spain and Italy alone account for more than half of the world’s death toll and are still seeing over 800 deaths a day each.

Experts say, however, that virus toll numbers across the world are being seriously under-represented due to limited testing and political decisions about which bodies are being counted. Unlike the U.S., France still does not count deaths that take place in nursing homes or in homes among its virus numbers — even though nursing homes are known to be a key coronavirus hotspot around the world.

‘’Europe must demonstrate that it is able to respond to this historic call,’’ Italian Premier Giuseppe Conte said late Saturday.

The crisis “involves all of the economic and social systems of the member states,” he said. “I will fight until the last drop of sweat, until the last gram of energy, to obtain a strong, vigorous, cohesive European response.”

President Donald Trump backtracked on a threat to quarantine New York and neighboring states amid criticism and questions about the legality of such a move. But the Centers for Disease Control and Prevention issued a travel advisory urging all residents of New York City and others in New York, New Jersey and Connecticut to avoid all non-essential travel for 14 days.

Shocking as that is for Americans, that stopped short of the restrictions imposed in Europe or elsewhere. Parisians are fined if they try to leave the city and South Africans can’t even walk their dog or buy liquor. In Italy, coffins are piling up despite three weeks of strict confinement and burials are being held with only one family member.

Spain’s government moved to tighten its lockdown and ban all non-essential work Sunday as it hit another daily record of 838 dead. The country’s overall official toll is nearly 6,000.

Spain’s emergencies chief expressed hope that “the outbreak is stabilizing and may be reaching its peak in some areas.”

But the crisis is pummeling world economies and putting huge strains on national health care systems. Spanish Prime Minister Pedro Sanchez called for a more vigorous response from the 27-nation European Union.

“It is the most difficult moment for the EU since its foundation and it has to be ready to rise to the challenge,” Sanchez said.

Spain, Italy, France and six other EU members have asked the union to share the burden of European debt, dubbed coronabonds in the media, to help fight the virus. But the idea has met resistance from other members, led by Germany and the Netherlands.

European countries have also resisted sharing masks or other medical equipment with their neighbors for fear that they, too, will need them in mass quantities soon. Many countries have turned to China, where the outbreak is easing, flying in cargo planes to get masks and other protective medical equipment.

Worldwide infections surpassed 660,000 mark, according to a tally by Johns Hopkins University. The United States leads the world with more than 120,000 reported cases but five other countries have higher death tolls: Italy, Spain, China, Iran and France.

Italy has more than 10,000 deaths, the most of any country.

Egypt shut its beaches as cases in the Mideast surpassed 50,000. Poland is considering delaying its May 10 presidential election, and Russian Prime Minister Mikhail Mishustin ordered his country’s borders closed on Monday.

Vietnam cut back domestic airline flights and closed restaurants and other businesses for two weeks. Vietnam has already quarantined nearly 60,000 people who entered from virus-infected nations.

For most people, the coronavirus causes mild or moderate symptoms, such as fever and cough that clear up in two to three weeks. But for others, especially older adults and people with existing health problems, the virus can cause more severe illness, including pneumonia, and lead to death.

More than 142,000 people have recovered, according to Johns Hopkins University.

New York Gov. Andrew Cuomo said defeating the virus will take “weeks and weeks and weeks.”

Health officials around the world have been urging people to keep a social distance of 2 meters (6 feet) from others to slow the spread of the virus but a new report from the Massachusetts Institute of Technology says that might not be enough.

It says a sneeze or cough from an infected person can expel microscopic virus droplets as far as 7-8 meters (23-27 feet) and those droplets can be suspended in the air for hours. The researchers said they wanted to warn the public about “the distance, timescale and persistence over which this cloud and its pathological payload can travel.”

In Detroit, which has a large low-income population, the death toll rose to 31 with 1,381 infections.

“The trajectory of Detroit is unfortunately even more steep than that of New York,” said Dr. Teena Chopra, medical director of infection prevention and hospital epidemiology at the Detroit Medical Center.

“This is off the charts,” she said. “We are seeing a lot of patients that are presenting to us with severe disease, rather than minor disease.”

Some U.S. states began to try to limit exposure from visitors from harder-hit areas. Rhode Island National Guard troops were going door-to-door in coastal communities to find New Yorkers and warn them about a mandatory 14-day quarantine for them.

Florida is setting up checkpoints to screen visitors from Louisiana. Chicago closed popular lakeshore parks after people ignored orders to stay home.

As others tightened controls, China eased more restrictions following the ruling Communist Party’s declaration of victory over the coronavirus. Subway and bus service resumed Saturday in Wuhan, the city of 11 million people at the center of the outbreak. Restrictions that bar Wuhan residents from leaving Hubei province end April 8.