Coronavirus Live Updates: Latest News and Analysis

New outbreaks — and mixed messaging — leave some Americans questioning their shutdown sacrifices.

With new cases of the coronavirus suddenly surging across multiple states that had low and manageable caseloads just months ago, confusion and anger is swirling among those who obeyed lockdowns and drastic social measures out of a sense of civic duty to help bring the U.S. outbreak under control.

On Friday, the country reported more than 45,000 new infections, its third consecutive day of record new cases, and a number of states have also been seeing record new levels. On Saturday, Florida, Nevada and South Carolina reported their highest one-day case totals. Before this week, the country’s largest daily total had been 36,738 on April 24.

Many business owners and workers who lost their jobs say they believe their leaders failed to prepare for the economic devastation that followed shutdowns that states adopted, to differing degrees, since March. And they say that recent reopenings undercut their sacrifices.

In recent weeks, some conservatives said they had an additional concern: After weeks of being told that going to church, attending funerals, and participating in protests was a willful, careless spurning of science, political leaders and some public health officials condoned — and even joined — the crowds protesting the killing of George Floyd.

“It’s just a real social whiplash,” said Philip Campbell, vice president of a pest control company in Central Michigan, who took part in the first protests against the lockdown in Lansing in April from the cab of his truck. “Two weeks ago you can’t go out because you are going to kill grandma. Now it’s ‘you have an obligation to go out.’ It leaves me feeling that the science and the public health authorities have been politicized.”

A number of states are reconsidering their reopening plans. In Florida and Texas, governors closed bars on Friday, as they scrambled to control what appeared to be a brewing public health catastrophe. All this is leaving people with a strange sense of déjà vu and a bitterness at public officials for what felt like a fumbling of people’s sacrifices.

“Are we doing a full circle? Yes,” said Judy Ray, 57, a cosmetologist and hairdresser in Florida who was laid off from her job at a barbershop at Walt Disney World Resort in March.

Some fault the state and city leaders who rushed to reopen while the virus surged in other corners of the country and now face daunting outbreaks in their own backyards. Others fault a lack of federal leadership, and a White House that defies expert guidance.

At a news conference on Friday, Vice President Mike Pence deflected a question about whether the Trump administration was sending mixed messages by reiterating public health officials’ advice while resuming crowded campaign rallies and refusing to wear masks.

“Even in a health crisis the American people don’t forfeit our constitutional rights,” he said. “We were creating settings where people can choose to participate in the political process, and we will continue to do that.”

Gov. Greg Abbott has acknowledged that his reopening plan had gone awry. In an interview with KVIA-TV in El Paso on Friday evening, he said, “If I could go back and redo anything, it probably would have been to slow down the opening of bars.”

At a news conference the same day, Lina Hidalgo, the county judge, urged people to stay home unless absolutely necessary and said that the situation was more dire than it had been in previous months, before Mr. Abbott’s statewide stay-at-home order began yielding on May 1 to his phased reopening.

“We are in a worse situation now than we were back then, and the only thing that worked back then was flattening that curve by staying home,” Ms. Hidalgo said, adding bluntly that the rise in cases occurred because “we opened too quickly.”

But because Mr. Abbott’s reopening orders supersede hers, Ms. Hidalgo could only strongly request that residents stay at home, not order them to do so, as she had previously. Some are worried that residents may not heed the request.

At the moment the county’s alert buzzed on telephones on Friday evening, urging residents to remain at home, wear a mask and cancel gatherings, a significant number were otherwise occupied. The bumper-to-bumper vehicles crawling along a section of Interstate 610 resembled precoronavirus traffic.

And at a shopping plaza off Interstate 10 with a view of the downtown skyline, the parking lot was packed as shoppers headed in and out of a grocery store, liquor shop and salon.

“There was widespread noncompliance, and that led to issues,” Mr. DeSantis said at a news conference in Fort Myers. “If folks just follow the guidelines, we’re going to be in good shape. When you depart from that, it becomes problematic.”

The return to stricter limits was one of the strongest acknowledgments yet that reopening has not gone as planned in a state where only days ago Mr. DeSantis had resisted calls to back down. Local officials expressed concern about whether residents would follow the rules, especially now, months into the crisis.

“People are tired of being in a stay-at-home environment, and they’re not going to be compliant,” said Carlos Migoya, the president and chief executive of the public Jackson Health System in Miami. “You can’t put the genie back in the bottle. We’ve got to deal with it being in the environment.”

In an apparent acknowledgment of the growing sense of anxiety over the surge in cases, Vice President Mike Pence decided to postpone a trip to Sarasota, Fla., that had been planned for early July.

Joe Gruters, a state senator from Tallahassee who leads the state Republican Party, said he learned of the decision on Saturday morning. The trip had been postponed as a safety precaution, but would be rescheduled for a later date, he said.

Mr. Pence had been scheduled to speak in Florida during a tour organized by America First Policies. “Out of an abundance of caution at this time, we are postponing the Great American Comeback tour stop in Florida,” the group’s website said.

The number of coronavirus infections in many parts of the United States is more than 10 times higher than the reported rate, according to data released Friday by the Centers for Disease Control and Prevention.

The analysis is part of a wide-ranging set of surveys initiated by the C.D.C. to estimate how far the virus has spread. It found, for instance, that in South Florida as of April 10, under 2 percent of people had been exposed to the virus. (The proportion is likely to be much higher now, given the surge of infections in the state.) The C.D.C. estimated 117,400 people in that region had been infected — about 11 times the reported number of 10,500 cases.

The results confirm what some scientists have warned about for months: that without wider testing, scores of infected people go undetected, and continue to circulate the virus.

“Our politicians can say our testing is awesome, but the fact is our testing is inadequate,” said Scott Hensley, a viral immunologist at the University of Pennsylvania who was not involved in the research.

The numbers indicate that even in areas hit hard by the virus, the overwhelming majority of people have not yet been infected, Dr. Hensley said.

“Many of us are sitting ducks who are still susceptible to second waves,” he said.

The difference between recorded infections and those that were missed was even more significant in Missouri, where about 2.65 percent of the population was infected with the virus as of April 26, although many people might not have felt sick. This number is about 24 times the reported rate: nearly 162,000 compared with the 6,800 believed to have been infected by then.

In the country’s south, the police in several seaside cities issued dispersal orders after large numbers of beachgoers caused huge traffic jams and engaged in antisocial behavior this week — including brawls, excessive drinking and even defecating in public.

The police in London and other cities like Derby, in central England, vowed to robustly disperse any unauthorized gathering. Over 140 officers in London have been injured while patrolling protests and breaking up unsanctioned parties in recent weeks.

And in Liverpool, the police have been given the power to disperse any gathering of more than two people in the center of the city, after thousands of supporters flouted social distancing rules on Friday when celebrating their soccer club’s English Premier League championship title.

When fans turned out in large numbers for the second night in a row to celebrate Liverpool’s title — its first in 30 years — Mayor Joe Anderson denounced the presence of “too many people intoxicated and causing antisocial behavior.”

In other international news:

  • More than 191,000 new infections were reported around the world on Friday, a single-day record. The total number of confirmed cases is nearing 10 million, and total deaths have passed 494,000. India’s caseload surged past 500,000 on Saturday.

  • Venezuela is struggling to control its first major outbreak, amid fears that the virus will collapse the country’s dilapidated health care system and worsen its humanitarian crisis. Medical workers at hospitals in the second-largest city, Maracaibo, say they are overwhelmed with Covid-19 patients, and treatment is complicated by a lack of running water and protective equipment, and frequent power cuts. The government has acknowledged only 39 deaths and cracked down on local journalists and medical workers who question it.

  • In Brazil, the pandemic is easing in big cities but gaining momentum in smaller towns. The Ministry of Health, in its latest epidemiological bulletin last week, reported that 65 percent of cases were concentrated outside state capitals and warned the virus had reached 88.6 percent of the country’s 5,570 cities. An epidemiologist at the University of São Paulo, Paulo Lotufo, warned of a “boomerang effect” as the sick and unemployed from smaller towns gravitate to bigger cities for care or jobs.

  • Fears of a second wave of coronavirus infections in China have receded somewhat. As of Saturday morning, the authorities had reported 297 cases in an outbreak in Beijing, and linked cases in at least four provinces. But the recent surge confirmed fears of sporadic flare-ups even after countries tame their outbreaks.

  • The European Union finished its list of countries whose travelers will be allowed in when the bloc reopens starting on July 1: Algeria, Australia, Canada, Georgia, Japan, Montenegro, Morocco, New Zealand, Rwanda, Serbia, South Korea, Thailand, Tunisia, Uruguay, Andorra, San Marino and Monaco. Travelers from the Vatican will be allowed, and also from China — so long as China allows in European Union travelers. Left out: the United States, Russia, and dozens of other countries suffering what are seen as uncontrolled outbreaks.

  • The Hong Kong police banned an annual pro-democracy march planned for Wednesday, the anniversary of the Chinese territory’s handover from British rule, citing concerns about the virus and potential street violence. Mainland China’s top legislative committee could pass a sweeping security law for Hong Kong on Tuesday.

  • As lockdowns loosen around the world and workers head back to their jobs, city leaders from Taipei to London to Bogotá are scrambling to address a new problem: gridlock as commuters retreat from mass transit into the safer space of their cars.

Nursing home deaths make up 43 percent of those in the U.S.

He and his colleagues compared 63 Covid-19 patients with 55 healthy people, some of whom had recovered from coronavirus infections.

One of the most striking aberrations in Covid-19 patients, the researchers found, was a marked increase in levels of a molecule that sends T cells to areas of the body where they are needed.

The result: a confused response from the immune system.

Some experts have wondered whether antiviral treatment makes sense for severely ill Covid-19 patients, if their main affliction is an immune system overreaction. But if the virus directly causes the immune system to malfunction, Dr. Hayday said, then an antiviral makes sense.

This week, in response to those findings, Norway reopened all of its gyms with the same safeguards in place that were used in the study.

The trial, begun on May 22, included five gyms in Oslo with 3,764 members, ages 18 to 64, who had no underlying medical conditions. Half were invited to go back to their gyms and work out, while the others were not allowed to.

The researchers found just one coronavirus infection, in a person who had not used the gym before he was tested; it was traced to his workplace. Some participants visited hospitals, but for conditions other than Covid-19.

Is there hope for gymgoers elsewhere?

“I personally think this is generalizable, with one caveat,” said Dr. Michael Bretthauer, a cancer screening expert at the University of Oslo who helped lead the study.

It is unlikely to be applicable, he said, in “places where there is a lot of Covid, or where people are less inclined to follow restrictions.”

The Times’s Claudio E. Cabrera was among the New Yorkers who rejoiced when the city’s salons and barbershops reopened this week. Here, he writes about the experience.

For the last three months, I’ve spent my Google Hangout work meetings wearing a Yankees cap.

Despite being a born-and-bred New Yorker, I am not a Yankees fan at all. But it was the only cap I had in my house to cover my lack of a shape-up, my lack of a haircut, with barbershops in the city closed because of the pandemic.

When people talk about the relationship between people of color and their barbers, they tend to forget that it’s not just that they raise your self-esteem and help you look good — they are people you can also share your life with, and who can share their life with you.

And they aren’t your typical friend. They don’t come out with you to the bar. You may never go on a guys’ trip with them. You have those friends.

But your barber is your part-time therapist, and sometimes you are his.

In late January, a doctor in Munich discovered Germany’s first coronavirus case, but the diagnosis made no sense. The patient reported only one possible contact with the infection: a business colleague visiting from China who had seemed healthy during her stay.

The visitor later told colleagues that she had not started feeling ill until after the flight back to China. Days later, she tested positive for the coronavirus.

Although it is now widely accepted that seemingly healthy people can spread the virus, scientists at the time believed that only people with symptoms could infect others.

“People who know much more about coronaviruses than I do were absolutely sure,” recalled Dr. Camilla Rothe, an infectious disease specialist at Munich University Hospital who diagnosed the businessman’s case.

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Reporting was contributed by Reed Abelson, Manuela Andreoni, Matt Apuzzo, Nicholas Bogel-Burroughs, Julie Bosman, Claudio E. Cabrera, Tess Felder, Selam Gebrekidan, Manny Fernandez, Abby Goodnough, Shawn Hubler, Miriam Jordan, Louis Keene, David D. Kirkpatrick, Gina Kolata, Anatoly Kurmanaev, Apoorva Mandivilli, Patricia Mazzei, Giulia McDonnell Nieto del Rio, Sarah Mervosh, Zach Montague, Dave Montgomery, Elian Peltier, Brad Plumer, Frances Robles, Somini Sengupta, Michael D. Shear, Jeanna Smialek, Mitch Smith, Sheryl Gay Stolberg, Sabrina Tavernise, Jim Tankersley and Vivian Wang.