For millions of Americans, the Covid-19 emergency, that disorienting stretch of lockdowns, mandates, free-floating anxiety and exhaustion came to a muted end sometime during the past couple of years, brought about by vaccines and antiviral drugs.

The expiration of the federal public health emergency on Thursday was a barely noticed formality.

But signs remain everywhere of a changed country: in the many thousands of families quietly grieving a loss, in the struggles of those suffering from long Covid and in the continued reliance by many Americans on one of the pandemic’s most hotly debated tools: the humble mask.

“This is my new norm,” said Nicole Uhiry, 38, who was masked and shelving books at a branch of the Des Moines Public Library. Ms Uhiry, who said wearing a mask made her more comfortable in her workplace, was unmoved by the government’s decision. “It doesn’t seem like Covid is going to go away. It keeps changing and evolving.”

In interviews around the country on Thursday, most people took in the news about the government’s decision with neither relief nor alarm, but with a sense of resignation. Many described being newly attuned to lurking risks to public health, and also to ways in which they could defend against these risks, often with the help of the government. Now, they were largely on their own.

“It’s not over, I know people who have the virus now,” said Maria Paula, 52, a home attendant who lives in Brooklyn. “I’m tired of mask wearing,” she said. “But the virus is here, it continues here.”

Ms. Paula is among those who, like a majority of the respondents in a survey conducted in mid-March by Monmouth University, believe that the pandemic is not over and might never be over. In that same poll, around half of respondents reported wearing a mask when out in public at least some of the time, and about 20 percent said they wore one most or all of the time.

In interviews, those who said they still consistently wore masks gave a wide variety of reasons. Some had respiratory problems or family members with compromised immune systems. Others noted that the pandemic was hardly over even if the federal emergency had ended.

There are plenty of illnesses beyond Covid-19, many said, describing the mask as a simple disease-fighting tool that perhaps should have been widely adopted a long time ago.

“In a lot of ways it has made us more aware of any kind of ailment out there that’s transmissible,” said Melissa Link, 52, a county commissioner in Athens, Ga., who recently wore a mask to a meeting when she had a head cold. “Nobody can afford to take days off work.”

For Ms. Link and others in states with conservative leadership, the emergency had been over for a long time, at least when it came to government rules. Many Republican governors, including the governor of Georgia, Brian Kemp, prohibited localities from requiring masks years ago, leaving the question of pandemic precautions almost entirely up to individuals or businesses.

But even in more liberal places, where masks were the norm throughout the pandemic and are hardly a rarity now, restrictions have long since been lifted.

“I’d be wearing a mask whether they have a mandate or not,” said Karen Stallard, 65, who was carrying groceries from a trip to Trader Joe’s in the Lincoln Park neighborhood of Chicago. She has respiratory problems, she said, and calls masks “a medical necessity.” But she added that the choice was a personal one, and should be. As for the federal health emergency, she said: “The time has come for it to end.”

Some said their continued mask wearing was rooted in a sense of social responsibility, out of concern for the elderly stranger one might pass in the supermarket or sit next to on the bus. “We never think about our old,” said Ariel Hsu, a 61-year-old retiree in Los Angeles. “They are the ones who have suffered the most from this.”

Others had more particular reasons. Lindsay Kolasa, 46, a herbalist living in Santa Barbara, Calif., said she wore her mask for her 5-year-old daughter, hoping to keep her safe from all kinds of viruses going around. Anastasia McTague, 28, standing at the front desk of a dry cleaner in Maitland, Fla., said she wore hers for her co-worker, whose mother died of Covid. “She has been kind of anxious about it the whole time, so I continue to wear the mask because it makes her feel better,” she said.

As with vaccine mandates and school closures, there was never a universal embrace of masks. A broad array of medical professionals have strongly encouraged wearing masks and mandates, citing studies that showed that masks slow transmission. But a steadily growing bloc of vocal citizens and public officials have condemned mandates as infringements on personal freedom.

Many of the remaining federal Covid mandates are being lifted along with the expiration of the public health emergency. Among other consequences, people will no longer be eligible for eight free at-home tests a month through their insurance. But few of those who were interviewed on Thursday were aware of the end of the health emergency, and those who had heard about it mostly said it would have little effect on their day-to-day lives.

“I took it with a grain of salt,” said Annie Gaines, 53, of Brooklyn, who still wears a mask when in close quarters with other people. “I’m curious: Why now?” she asked of the announcement. “Maybe it’s the vaccine rate? It seems like a moving landscape.”

This sense of puzzlement was among the more common reactions: Why now, what does it mean and what had really happened over the past three, strange, awful, bewildering years?

“What was it all about?” said Diane Soto, who was wearing a mask and walking into a Chinese restaurant on Thursday afternoon in Altamonte Springs, Fla. “I don’t know.”

Reporting was contributed by Eric Adelson, Angela Chen, Mark Guarino, Antonio Mejias-Rentas, Ann Hinga Klein and Nate Schweber.