WASHINGTON — After weeks of declining coronavirus deaths and hospitalizations, new hot spots of infection have emerged, and disease experts warn that the spread of a more dangerous variant and a too-rapid rush to return to normal life could prolong the historic health emergency.

Caseloads are down nationally, and tens of millions of people are fully loaded with antibodies to the virus, with more than 2 million people getting doses of vaccine every day. But the virus continues to pose a real and present threat, with about 55,000 new infections daily.

Michigan has seen a rise in hospitalizations and positive test results. Minnesota’s numbers are creeping up, as are Maryland’s and New Jersey’s. Many places, including New York City and surrounding counties, are no longer seeing steady declines in cases, despite intensive vaccination efforts.

“There’s a resurgence going on here,” said disease tracker David Rubin, director of PolicyLab at Children’s Hospital of Philadelphia. It is too soon to call this a “wave,” and he does not foresee a return to the level of cases reported during the winter, he said. But Rubin said case numbers are flat or creeping up in much of the Northeast, the Mid-Atlantic and parts of the Upper Midwest.

“There’s clearly been a change here in the last couple of weeks,” Rubin said.

Behavior is changing in this pandemic-fatigued nation. This week is set to be a major turning point for reopenings. Wedding parties are kicking off again in New York. Pennsylvania is allowing more fans into stadiums. And most of Maryland has opened up restaurants.


Air travel hit a pandemic record during the weekend, with 1.2 million to 1.3 million people traveling each day from Thursday to Sunday. That was more than any four-day period since March 2020.

Infectious-disease experts are imploring people to stay cautious and respect the lingering threat of the virus. With the end of the coronavirus pandemic potentially in sight, experts recognize that this is one of the trickiest phases of the crisis — epidemiologically and psychologically.

“It’s like we’re in the homestretch where it hurts more than any other time,” said Mary Jo Trepka, an epidemiologist at Florida International University, comparing the situation to the end of an 800-meter race. “But if you give up now, you’ve given up the entire race.”

The stay-the-course message is colliding with human nature. Winter is releasing its grip. Restaurants are opening, as are stadiums, with capacity limits. People are desperate to see friends and family members they have missed for so long. This may be an especially challenging part of the pandemic, said William Hanage, an epidemiologist at the Harvard University T.H. Chan School of Public Health.

“I keep trying to say, ‘Just hold off, hold off, hold off, because the vaccine’s coming,’ ” he said.

Ten months ago, the nation was in a similar situation, emerging from a catastrophic surge, eager to reopen businesses and resume travel, with some states and cities largely ignoring Centers for Disease Control and Prevention guidance and rushing to relax restrictions that had been effective in reducing infection numbers. That predictably preceded a wave of cases in the Sun Belt, and later in the Upper Midwest, leading to another round of shutdowns.


This time, with the country recovering from the protracted fall and winter surge, the situation is different because there is more immunity resulting from previous infections and from vaccinations. Most people in the country older than 65 have had at least one dose of vaccine. The heightened protection in the older age brackets means lower levels of hospitalizations. About 41,000 people are hospitalized in the United States with COVID-19, the disease caused by the coronavirus, according to Washington Post data. That is less than a third of the winter-surge peak in early January.

The death toll has been dropping, too, and in the near future, the average for daily deaths could drop below 1,000 for the first time since the fall.

But there are places with numbers going in the wrong direction. Michigan’s daily infection numbers have doubled, from 1,045 on average on Feb. 21, to 2,223 as of Monday, according to The Post’s data. Hospitalizations have also increased in Michigan.

Nationally, most adults remain unvaccinated, and millions of those people are in higher age brackets or have chronic conditions making them more vulnerable to severe illness from the coronavirus.

CDC Director Rochelle Walensky on Monday urged the public to remain vigilant and to not let down its guard. She pointed out that Europe — which has been slower to vaccinate its population — is enduring another surge of cases, with France and Italy imposing shutdowns.

“They simply took their eye off the ball,” she said. “I’m pleading with you for the sake of our nation’s health. These should be warning signs for all of us.”


Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota, said the spread of the B.1.1.7 variant, first identified in the United Kingdom, began with small outbreaks in that nation that snowballed even though most of the country was shut down.

Research published Monday in the journal Nature showed that B.1.1.7 is more probable to cause a fatal illness than earlier variants of the coronavirus, technically named SARS-CoV-2. The study found a 61% higher risk of death from the variant. “Our analysis suggests that B.1.1.7 is not only more transmissible than preexisting SARS-CoV-2 variants, but may also cause more severe illness,” the study states.

By relaxing restrictions, Osterholm said, the United States is moving in the opposite direction of Europe, and that makes the country more vulnerable to this variant. European countries hit hard by the variant did not experience rising case numbers until the variant accounted for more than half of circulating strains — a milestone the United States could hit in the coming week, he warned.

“What Europe is telling us is that we haven’t yet begun to see the impact of B.1.1.7 here,” he said. “Everyone wants me to say nothing is going to happen. We have such an optimism about the vaccines, which we should. But right now we have to be very cautious.”

The virus is slamming into obstacles as it attempts to circulate. No longer is it spreading through a population with zero immunity, as was the case a year ago. The U.S. government reported Monday that the United States was averaging 2.4 million shots daily during the past week.

And an unknown but presumably large number of people have some level of lingering immunity from being infected by the virus and surviving. It is unclear how long natural immunity lasts, but one study in January showed that most people still had antibodies eight months after they became sick.


Vulnerability to reinfection remains unclear. The consensus is that the second time around, a person would probably become less sick, but the novel nature of this virus and the still-limited research keep this in the no-one-knows category. Any forecast is complicated by the variants, including ones first seen in South Africa (B. 1.351) and in Brazil (P. 1) that appear to lower the ability of antibodies to thwart the virus.

Of the variants, B.1.1.7 is by far the most widespread in the United States. Florida leads the nation, with 738 identified cases, followed by Michigan, with 616, according to CDC numbers posted Sunday.

New York City-area residents were preparing this week for a major reopening as residents marked the one-year shutdown anniversary. Governors of Connecticut, New Jersey and New York cited declines in cases and an accelerated timetable for vaccinations in announcing a loosening of restrictions.

As of Monday, wedding receptions were allowed again in New York City, with limitations. Couples on dance floors must remain six feet apart.

On Friday, indoor dining capacity jumps to 50% in the five boroughs of New York City and 75% outside those areas. In Connecticut, all capacity limits will be lifted at restaurants and many other businesses.

The New York City area has its own variant, known as B. 1.526, which is spreading quickly along with B.1.1.7. The two variants last week combined for more than 50% of New York City’s cases. Scientists believe they are more transmissible than previous versions, and some experts express concern that vaccine or treatments may be less effective against B. 1.526.


At a news conference this week, New York Mayor Bill de Blasio painted an optimistic picture, touting an ambitious timeline for vaccinating the full population within seven weeks.

“We’re watching the variants very closely,” the Democratic mayor said, “but I’ve got to tell you, the overall trajectory looks very good right now.”

Neville Sanjana, a geneticist at the New York Genome Center, an independent, nonprofit research institution, said research published in the past few weeks has eased some worries about some of the variants’ ability to escape vaccines. One study published in early March by Duke University researchers found that when the B.1.1.7 variant was circulating, there was a twofold reduction in neutralizing antibodies induced by the Moderna or Novavax vaccines. Sanjana said that reduction is actually modest and “not really a cause for concern.”

The second study was posted online at the end of February before peer review by La Jolla Institute for Immunology researchers Alessandro Sette and Shane Crotty. It found a negligible effect from the B.1.1.7 variant, as well as those first identified in Brazil and South Africa, on another part of the immune system, the T-cells.

Sanjana described the antibody response as disrupting the handshake that allows the coronavirus to bind with our cells, and the T-cells as commando troops that “go door to door surveilling cells that are already infected” and destroy them.

Still, Sanjana cautioned that the New York numbers are flat despite the increase in vaccinations.


“The virus is still spreading at an extraordinary rate,” he said. “We’re not seeing a large drop in cases, so it pays to be prudent in discussions about opening.”

In Minnesota, case counts have been rising slowly during the past week, worrying officials, though numbers are low compared with November and December. The state is being watched closely because of an outbreak of cases with the B.1.1.7 variant in Carver County, about 35 miles outside Minneapolis, that has been linked to school sports. State officials recommended a two-week countywide pause on youth sports. The Minnesota Department of Health reported a 62% increase in coronavirus cases in the county from Feb. 24 to March 4.

Gov. Tim Walz, a Democrat, said that, while officials are monitoring the situation in Carver, “normalcy is on the horizon” and many remaining coronavirus restrictions would be reduced.