After a holiday surge that killed more than 7,000 residents, coronavirus infections in D.C., Maryland and Virginia are declining steadily — an encouraging, but precarious, mark of progress, officials and experts say.

On Thursday, the region’s seven-day average of new daily cases fell to the same levels as mid-November. Hospitalizations were also down to pre-Thanksgiving levels, and deaths had dropped to half of their January peak.

“I have rarely offered words of optimism. But I have been watching the numbers, and I’m beginning to feel optimistic,” said Eric Toner, a senior scholar with the Johns Hopkins Center for Health Security. Given the increased use of masks and the number of residents who have achieved some degree of immunity, either from surviving covid-19 or receiving the vaccine, “we have reason to believe that maybe the worst is over,” he said.

Nonetheless, with an average of more than 3,000 new cases daily, experts say it’s still too early to lift major restrictions on social and commercial activity.

Limited supplies of the vaccine, along with distribution errors and complications, mean that it will probably take months before D.C., Maryland and Virginia achieve herd immunity. Meanwhile, complacency could allow highly contagious variants of the coronavirus to take hold.

“There’s still kindling to light the fire,” Montgomery County Health Officer Travis Gayles said, citing the emergence in the Washington metro region of the variants first detected in South Africa and the United Kingdom. “And that’s a huge concern for us.”

Elected officials are likely to face immense pressure to reopen, similar to what happened in the summer following a wave of shutdowns. But acting too early could send infections rebounding, Toner said, at a time when a “safe landing” to the pandemic is within reach.

Rohit Modak, an infectious-disease specialist at Virginia Hospital Center, warned that scientists still don’t know how the virus could mutate, and even as more residents get inoculated, they will not be totally protected from getting or transmitting the infection.

“You’re not bulletproof,” Modak said. “We just don’t know what’s coming down the road and how it will play out.”

Baltimore and Howard County are raising limits on certain in-person gatherings to align themselves with Maryland’s Phase 2 guidelines. But officials in Montgomery and Prince George’s counties, which collectively account for nearly a third of the state’s population and 36 percent of its coronavirus cases, say they don’t plan to roll back restrictions yet.

Statewide, Maryland also does not have imminent plans to reverse policies set in place during the fall surge, including advisories to quarantine after travel and caps on the size of indoor social gatherings, said Michael Ricci, a spokesman for Gov. Larry Hogan (R).

He said the state is watching to see whether the Biden administration calls for greater reopening, but added that setting any timetable or threshold to roll back restrictions is difficult given the still-limited vaccine supply.

“People understand we have to hunker down and get through the winter,” Ricci said.

Virginia Gov. Ralph Northam (D) loosened minor restrictions on Wednesday and said more could be coming, but he emphasized that the state is “not out of the woods yet.”

Although Virginia’s seven-day average for test positivity has dropped from 17 percent in early January to under 9 percent, that number still indicates a high rate of transmission, according to federal guidelines.

The state imposed a modified stay-at-home order on Dec. 10 and renewed it in late January.

Northam acknowledged that as the weather improves, there will probably be more calls to ease restrictions, particularly from businesses. Citing major outdoor events such as NASCAR races and minor league baseball games, Northam said his advisers are “in discussions” with owners of large venues about finding a way forward.

As in earlier seasons of the pandemic, however, certain jurisdictions in Virginia and Maryland may opt out of the statewide reopening.

“Until we start getting much higher volumes of people getting vaccinated, it wouldn’t make sense for us to reopen some of the floodgates and send a message to the community that things are normal,” said Jeff C. McKay (D-At Large), chairman of the Fairfax County Board of Supervisors.

Natalie Talis, population health manager at the Alexandria Health Department, said officials are wary of complacency, even as they see more robust compliance with mask-wearing — including double-masking — and vaccinations.

“When people see the lower numbers, it’s very easy for people to let their guard down and do things they may not otherwise do,” Talis said.

D.C. Mayor Muriel E. Bowser (D) expressed optimism about the city’s improving coronavirus metrics Wednesday but declined to say whether she would consider loosening restrictions that she put in place in November, when infections began to spike.

Ankoor Shah, head of the city’s vaccine program, noted that cases are still higher than during most of last year and there is still “substantial community spread.” The city’s most recent data shows an average case rate per 100,000 residents of 16.9, far higher than the standard of five that officials set for themselves to move into Phase 3 of their recovery plan.

When metrics do allow for reopening, some officials say, the process could look different from the summer and fall of last year. Business leaders hope the benefit of hindsight will allow this wave of reopenings to be more deliberate and coordinated among members of the Washington metro region, as well as between state and local governments.

In the fall, public schools stayed shuttered as restaurants and other businesses reopened their doors. D.C. and Virginia have resumed some degree of in-person instruction for hundreds of public school students and teachers, and Maryland is set to join them in March.

Officials in Montgomery, Howard, Baltimore and Anne Arundel counties said they are closely monitoring the return to in-person instruction. Baltimore County Executive John Olszewski Jr. said the implications of the public school system on the county’s caseloads “will influence any future decisions on reopening.”

Montgomery County Council member Will Jawando (D-At Large) said he received pushback from some residents and business leaders last week after being one of two lawmakers to vote against lifting a ban on indoor dining. In council discussions, he said the suburb of 1 million should keep all existing restrictions in place until schools successfully reopen — and stay open.

The county “didn’t do it exactly right” in the way it lifted restrictions last year, Jawando said in an interview. He added that there was “understandable pressure” to loosen rules on youth sports, indoor dining, retail and other activities, leading to a mixed and often complicated approach “that had a muddled effect on getting our cases consistently down.”

“There’s no perfect solution. . . . But with the mental health issues, the anguish, the learning loss, schools have got to be the top priority,” Jawando said.

Boris Lushniak, dean of the University of Maryland School of Public Health, said prioritizing schools would have a helpful “trickle-down effect”: With kids in classes, more parents will be able to reenter the workforce. Reopening businesses and restaurants could come next, followed by some industries returning to work in person.

But he said mass gatherings may have to wait. “That vision of filling up concert venues, having the Nats stadium with rows of people . . . that’s going to take us much longer.”

Industry representatives want to see greater coordination in reopening.

The Restaurant Association of Maryland is not pushing Hogan to expand dining restrictions in the near future, but wants Montgomery and Prince George’s to match the rest of the state in allowing 50 percent occupancy indoors, said Marshall Weston, the group’s president. “We would love to see the entire state be on the same page,” he said.

Kathy Hollinger, chief executive of the Restaurant Association Metropolitan Washington, said she hopes officials can avoid what she called the “stop-and-start” approach, where restrictions are lifted, then reimposed.

“For restaurants, there is a lot of thought and a lot of effort that goes into moving forward and taking steps back,” Hollinger said.

But public health experts say that when it comes to managing the virus, it’s crucial that local and state governments remain nimble. The unwillingness to roll back reopening measures — even when cases worsened — compromised national efforts to contain the virus last year, Lushniak said, allowing pockets of transmission to fester and spread.

“The second we see numbers are heading in the wrong direction, we have to be ready to rescind,” he added.

Despite the plummeting caseloads, Lushniak said, people need to keep their masks on and avoid crowds — now more than ever before.

“We’re so close to the end line. . . . If we give up now, that line is going to be further and further away.”

Michael Brice-Saddler, Rachel Chason, Antonio Olivo, Jenna Portnoy and Julie Zauzmer contributed to this report.