Cases Soar in Italy, Iran and South Korea as Alarm Grows

Japan closed its schools for at least a month. Iran canceled Friday Prayers in major cities. Saudi Arabia barred pilgrims from its holiest sites. Stock markets tumbled. U.S. officials called for many more people to be tested.

As cases of the new coronavirus soared in Europe and the Middle East, and infections cropped up in several additional countries — cumulatively at least 48 so far — the signs were everywhere on Thursday that the epidemic shaking much of the world was being viewed with growing alarm.

[Read: ‘No way out’: In China, coronavirus takes a toll on other patients.]

And the illness, first detected in China in December, appeared to enter a troubling new phase: Infections were found in patients in Germany and the United States who had no known risk factors, like having traveled to an affected area, suggesting that the virus could be spreading undetected in their communities.

Conditions continued to ease in China, where the authorities lifted some citywide lockdowns and the country struggled to revive major segments of the economy that had ground to a halt. Around the world, the new illness, dubbed COVID-19, stirred fears that other nations could suffer as China has.

In both Italy and Iran, with two of the biggest outbreaks, the number of reported infections more than doubled in just two days, approaching 900 combined, and people who had recently been to those countries continued to seed new outbreaks elsewhere. Kuwait reported 43 new cases, all of them tied to Iran.

South Korea, with the largest outbreak outside of China, reported 256 new cases Friday, bringing its total to 2,022, and officials made plans to test an estimated 200,000 members of a church that has become one of the epidemic’s hot zones.

[Read: He blames ‘evil’ for South Korea’s coronavirus surge. Officials blame him.]

Several countries registered new infections that illustrated the diverse ways the pathogen could cross borders. In Britain, one case was linked to Tenerife in the Canary Islands of Spain, where a hotel remains under lockdown after four guests tested positive.

In the United States alone, thousands of people who had been at risk of exposure to the virus were under quarantine — most often voluntary — and federal officials issued new warnings about the potential spread of the disease, including the possibility that schools could be forced to close.

U.S. workers were sent into quarantine area unprotected and unprepared, complaint says.

Federal government health workers were not given proper medical training or protective gear when they were sent to assist Americans who had been quarantined for possible exposure to the coronavirus, according to a whistle-blower complaint.

Staff members entered quarantine areas at Travis Air Force Base and March Air Reserve Base in California, interacted with the people who were in isolation and then moved freely around and off the bases, the complaint said.

The whistle-blower, described as a senior leader at the Department of Health and Human Services, said at least one worker stayed in a nearby hotel and left California on a commercial flight.

Many of the health workers were unaware of the need to test their temperatures three times a day, the person said. The complaint was submitted to the Office of the Special Counsel, and a portion was obtained by The New York Times.

The employees were not given training in safety protocols until five days after they were ordered into quarantined areas, including a hangar where evacuees from coronavirus hot zones in China and elsewhere were being received, the whistle-blower said.

President Trump has sought to play down the danger of a domestic outbreak, amid bipartisan concerns about a sluggish and disjointed administration response to an epidemic that public health officials say is likely to spread in the United States.

The first U.S. case of coronavirus infection in a patient with no known risk factors — travel to a hot zone or contact with another person known to be infected — emerged this week near Travis Air Force Base.

In a statement on Thursday, the Department of Health and Human Services acknowledged the complaint, saying, “We take all whistle-blower complaints very seriously.”

Stock market suffers worst daily drop since 2011.

Global markets tumbled for a sixth consecutive day on Thursday, dragging the S&P 500 down more than 10 percent in just over a week, reflecting rising fears over the coronavirus spreading quickly around the world.

The benchmark index fell 4.4 percent on Thursday, the worst single-day slide for the market since August 2011. It is on pace for its worst weekly performance since the 2008 financial crisis. Stocks in Europe and Asia were also hard hit on Thursday.

The sell-off came after infection figures in Europe and the Middle East continued to soar and after public health officials in the United States and Germany said new patients in each country had no known connection to others with the illness. That complicates efforts to track the virus, isolate infected people and keep the virus from spreading further.

The speed of the slump has been stunning, with the S&P 500 falling more than 10 percent from its Feb. 19 high, a drop that Wall Street labels a market correction to suggest the decline is more significant than a few days of downbeat trading.

The last time stocks in the United States fell more than 10 percent was late 2018, when investors worried that the trade war and rising interest rates might tip the U.S. economy into a recession. The Dow Jones industrial average also fell into a correction on Thursday, as did shares in London.

Stocks in Europe and Asia were also hard hit on Thursday, and the blow to investor confidence spread far beyond stocks. Crude oil fell more than 4 percent, and money flooded into Treasury markets, pushing prices sharply higher, and yields — which move in the opposite direction — to once unthinkable depths.

New York may have its first case, city officials say.

New York City officials said on Thursday they had a possible coronavirus patient and were sending a sample for testing to the Centers for Disease Control and Prevention in Atlanta. The patient had respiratory symptoms and had recently traveled in Italy, which has emerged as a hub of the coronavirus, health officials said.

Health officials said the patient was under 50, but provided few other biographical details. This was the first suspected case in New York City since the C.D.C. expanded its testing criteria to account for the spread of the virus in a number of countries beyond China, including Iran, Italy, Japan, and South Korea.

New York City has had no confirmed cases of the virus so far. Seven patients had previously been deemed potential cases, only to be ruled out after testing.

Virus testing will cast a wider net, C.D.C. says.

Federal health officials on Thursday approved coronavirus testing of significantly more people, a day after a California patient who had no known risk factors tested positive for the virus.

Testing for the infection — which is now done almost entirely by the Centers for Disease Control and Prevention in Atlanta — has been administered only to patients who had been to China recently or who were in touch with a person who had a confirmed case of the illness, though exceptions could be made.

The C.D.C. expanded the criteria to include people with symptoms of illness who had traveled to Iran, Italy, Japan and South Korea. They will also cover severely ill patients with acute lower respiratory sickness who are hospitalized, even if no source of coronavirus exposure has been identified, when there is no alternative diagnosis.

The California patient had to wait days to be tested because of restrictive federal criteria, despite doctors’ suggestions. Public health officials said the person was a resident of Solano County, in Northern California, but they have not disclosed any other information to protect the patient’s privacy.

Doctors at the University of California, Davis Medical Center considered the novel pathogen a possible diagnosis when the patient was first admitted last week.

The patient in California and one in Germany had not traveled to any country with an outbreak, or been in contact with anyone known to be infected, suggesting that the virus had spread within their communities.

“That would suggest there are other undetected cases out there, and we have already started some low-grade transmission,” said Dr. William Schaffner, an infectious disease specialist at Vanderbilt University.

The number of coronavirus cases in Italy soared on Thursday, and the count of European countries reporting infections rose to 15.

Leaders are struggling to find a balance between slowing the epidemic and avoiding panic or economic disruption — debating, for example, the wisdom of holding major events that draw from across the continent.

The Netherlands, Denmark, Estonia, Norway and Romania all reported infections for the first time, joining Italy, Austria, Croatia, France, Germany, Greece, North Macedonia, Spain, Sweden and Britain.

Italian officials reported 650 cases as of Thursday night — up from 400 a day earlier — with 17 deaths. The number of infections had doubled in just two days, as Italy grapples with the largest outbreak outside of Asia, centered in the northern region of Lombardy.

Whole towns have been isolated, and Lombardy’s governor, Attilio Fontana, started a period of self-isolation after a co-worker tested positive.

Most other affected European nations have just a handful of cases, but national leaders say that these early days will prove crucial.

“We have before us a crisis, an epidemic that is coming, we know that certain countries are already much more affected than us,” President Emmanuel Macron of France said during a visit to the Paris hospital where a coronavirus patient died this week. “We are going to have to confront it as best we can, even as life goes on.”

Hours later, officials in France reported that the number of cases there had jumped to 38, from 18 a day earlier.

In Spain, where there are 17 cases, the latest patient, announced Thursday, was a soccer fan from Valencia — one of thousands who had traveled to Milan, the capital of Lombardy, earlier this month to watch a Champions League match.

The coronavirus toll in Iran continued to climb fast on Thursday, as a member of President Hassan Rouhani’s cabinet fell ill — one of at least seven government official to test positive, including one prominent cleric who has died.

The official, Iran’s highest ranking female official, attended a cabinet meeting on Wednesday, in which she was in close contact with top leaders, including Mr. Rouhani.

The Health Ministry reported 245 cases, up from 139 on Wednesday, with 26 deaths. Health experts say that given the number of fatalities, the number of infections is probably far higher than the official figure.

Dozens of cases involving people who recently visited Iran have surfaced in recent days in Bahrain, Lebanon, Afghanistan, Oman, Iraq, the United Arab Emirates, Pakistan, Georgia and Kuwait.

The sick cabinet member, Vice President Masoumeh Ebtekar, is Mr. Rouhani’s deputy for women’s affairs. A young revolutionary during the Tehran hostage crisis four decades ago, Ms. Ebtekar was a spokeswoman for the captors of the 52 Americans held at the U.S. Embassy.

Despite the Iranian authorities’ earlier claims that the outbreak, centered in the city of Qom, had been exaggerated by enemy propaganda, they canceled Friday Prayers in Tehran and 22 other cities, and ordered schools and universities closed until March 21. All cultural and sports events will remain shut down for another week, the Ministry of Culture said.

Hadi Khosroshahi, 81, a prominent cleric and former ambassador to the Vatican, was sickened by the coronavirus and died in a hospital, Iran’s official media have reported. The outbreak has also killed Elham Sheikhi, 22, a member of the women’s national soccer team.

The virus can be deadly, but so far, it most often isn’t.

The new coronavirus has sown fear and anxiety, with more than 82,000 cases and nearly 3,000 deaths.

But so far, it appears that the vast majority of those infected have only mild symptoms and make full recoveries. And those who get the virus develop powerful antibodies that should protect them from reinfection.

In China, people who have been infected are being asked to donate blood plasma, in the hope that their antibodies can be used to treat sick patients.

The largest study of the virus to date, published by China’s Center for Disease Control and Prevention, concluded that 81 percent of the 44,000 cases confirmed in China by mid-February were mild — defined by the study’s author’s as involving little or no pneumonia.

Just under 14 percent were deemed severe, involving shortness of breath, low blood oxygen saturation or other lung problems. Just under 5 percent were critical, involving respiratory failure, septic shock or multiple organ dysfunction.

By Thursday, of the 78,487 confirmed cases in China, 32,495, or 41 percent, had been discharged from the hospital, according to China’s National Health Commission. About 8,300 patients were in serious condition. More than 2,700 people had died, giving an overall mortality rate of 2.3 percent, far higher than the seasonal flu’s rate of about 0.1 percent.

The number of mild cases creates its own complications.

Those with few or no symptoms may not know they have contracted the virus, or may misidentify it as a cold. They may then continue their daily lives, coming into close contact with others and spreading the virus without anyone knowing.

The White House on Thursday directed the government’s health officials and scientists to clear all coronavirus statements and public appearance with the office of Vice President Mike Pence, according to several officials familiar with the new approach.

Dr. Anthony S. Fauci, one of the country’s leading experts on viruses and the director of the National Institute of Allergy and Infections Diseases, told associates that the White House had instructed him not to say anything else without clearance.

President Trump selected Mr. Pence on Wednesday to coordinate the government’s response to the virus. In turn, Mr. Pence said on Thursday that he had selected Dr. Deborah L. Birx, who directs U.S. efforts against H.I.V. and AIDS, to serve as the Coronavirus Response Coordinator for the White House.

The announcements were intended to show that Mr. Trump and those around him are taking the potential threat to the health of Americans seriously, though Mr. Trump himself has downplayed the danger.

But three people have now been designated as the administration’s primary coronavirus official.

In announcing Mr. Pence’s coronavirus responsibilities, Mr. Trump said, “Mike is going to be in charge, and Mike will report back to me.” Mr. Pence says it will be Ms. Birx. Meanwhile, Alex M. Azar II, the health and human services secretary, remains the chairman of the government’s coronavirus task force — whose meeting Thursday Mr. Pence is scheduled to lead.

The insertion of Mr. Pence and then Dr. Birx into the government’s response further erodes Mr. Azar’s traditional role. Mr. Trump has told people that he considers Mr. Azar to be too “alarmist” about the virus.

Health officials in Germany reacted aggressively on Thursday after a man with no known connection to anyone infected with the coronavirus tested positive for the illness.

In addition to closing schools in the community where he lived, they reached out to hundreds of people who took part in a carnival celebration over the weekend where the man was also present, urging them to stay home for 14 days.

Karl-Josef Laumann, the health minister for the state of North Rhine-Westphalia, where the man lives, said that the authorities were still trying to figure out how the man had contracted the virus.

He remains critically ill and cannot provide information about his recent travels, including the period of time when he was infected and contagious but not showing symptoms.

Still, German officials said they would resist taking measures like those seen in China and, to a lesser extent, in Italy, where entire towns and cities have been locked down.

They cautioned against panic, pointing to success in preventing the spread of the virus last month through simply encouraging people to stay home.

Federal officials warned this week that a coronavirus outbreak could force schools to close for a long period.

The U.S. announcement caught educators and parents off guard, leaving them asking how to manage such a crisis.

Dr. Nancy Messonnier, director of the National Center for Immunization and Respiratory Diseases, suggested that a temporary system of “internet-based teleschooling” could replace traditional schools.

But most schools have no experience in providing online instruction on a large scale, and American families have uneven access to computers and broadband internet.

Parents would be forced to juggle their own work responsibilities with what could amount to “a vast, unplanned experiment in mass home-schooling,” said Kevin Carey, vice president for education policy at New America, a think tank.

Even as they struggled to absorb the federal warning, schools were busy making their own plans.

Many districts have already sent home letters about the coronavirus, asking parents to keep sick children away from school and to remember basic prevention measures like hand washing, cough covering and flu vaccination.

Reporting and research was contributed by Sheri Fink, Melissa Eddy, Salman Masood, Marc Santora, Russell Goldman, Carlos Tejada, Kevin Granville, Geneva Abdul, Choe Sang-Hun, Zoe Mou, Daniel Victor, Roni Caryn Rabin, Denise Grady, David Yaffe-Bellany, Ed Shanahan, Andrew Keh, Ben Dooley, Motoko Rich, Vivian Yee, Michael D. Shear, Emily Cochrane, Aurelien Breeden, Raphael Minder, Matina Stevis-Gridneff, Elaine Yu, Richard Pérez-Peña, Emma Bubola, Dana Goldstein, Julie Bosman and Matt Phillips.