Teachers, fearful of returning to classrooms during the pandemic, are facing new encouragement — and new pressure — to go back, raising the prospect that in-person school could resume in many communities before the school year is out.

The Centers for Disease Control recommended Sunday that states prioritize teachers as part of the second group of people eligible for the coronavirus vaccines.

Two days later, Congress cleared a coronavirus aid package with $54 billion for K-12 schools, which, if the president signs it, is expected to help pay expenses associated with in-person education. That could include protective equipment such as masks and plexiglass dividers, upgrades to ventilation systems and additional staffing.

And President-elect Joe Biden is pushing for schools to reopen for in-person teaching. His nominee for education secretary, Miguel Cardona, worked to reopen schools in his home state of Connecticut, and all but one of about 200 districts offered some in-person school at some point this fall.

Biden says he wants most schools open by the 100-day mark of his presidency, this spring. “Reopening schools safely will be a national priority for the Biden-Harris administration,” Biden said Wednesday in introducing Cardona, Connecticut’s schools commissioner. He called his 100-day goal “ambitious but doable.”

Adding to the reopen pressure is emerging evidence of deep learning losses among children engaged in remote education and growing data showing the virus is not spreading much inside schools.

It puts teachers in a precarious position. Many districts stayed shut because of their fears of going back, and some complain that teachers have gone from heroes to villains in the public mind.

“People loved teachers in March when we were doing all this stuff, and now they think we’re lazy and scared and demanding,” said Sherry East, president of the South Carolina Education Association.

She said that districts operating in person in her state have not seen elevated virus transmission, and it’s possible that teachers overreacted to the risks of return. Nonetheless, she said, teachers are genuinely scared of becoming infected with a deadly disease, particularly as infection rates surge.

“That fear is real for them, whether it’s unwarranted or not. It is a real fear,” she said. She added: “Face-to-face (teaching) is absolutely best for most kids, and we need to get there as quickly as we can.”

The vaccine rollout could be a game changer, although it’s not clear how quickly.

The CDC advisory panel recommended Sunday that teachers be included in the next group of about 30 million “front line essential workers” vaccinated against the coronavirus. That would put teachers alongside people working in meat plants, grocery stores and prisons, as well as about 19 million people age 75 and older.

Each state will decide for itself how to prioritize different groups, and lobbying is intense on behalf of teachers in several states. Some governors have said they will prioritize teachers.

In Utah, Gov. Gary R. Herbert (R) is including teachers in the vaccination group immediately after health-care workers. That means many teachers will get both doses of the vaccine next month.

Salt Lake City school leaders had planned to bring back elementary school students on Jan. 28. Now, citing the vaccines, interim superintendent Larry Madden is asking the school board for approval to reopen middle and high schools on Feb. 8, a week after teachers are scheduled to get their second dose.

In Arizona, Gov. Doug Ducey (R) signaled the same. “We want our schools open and our teachers protected,” he said this month. “Teachers are essential to our state, so under our plan, they will be prioritized.”

“There appears to be growing impatience on the part of parents to reopen as quickly as we possibly can, and this vaccine and the additional money is going to help us to do that,” said Michael Casserly, executive director of the Council of the Great City Schools, a coalition of large urban public school systems.

The developments come as some districts are increasing pressure on teachers to return to classrooms.

In Chicago, where the teachers union has resisted, the school system is set to try to force them back. Buildings will begin reopening next month, and some teachers must return as soon as Jan. 4, said Chicago Public Schools spokeswoman Emily Bolton. The Chicago Teachers Union unsuccessfully petitioned the Illinois Educational Labor Relations Board to halt the reopening plan but has floated the idea of a strike.

Schools CEO Janice Jackson told the Chicago Sun-Times earlier this month that teachers “don’t have a choice of opting in or out,” unless they are approved for medical leave, and could face consequences for failing to show up.

“If they don’t show up to work, it will be handled the same way it’s handled in any other situation where an employee fails to come to work,” Jackson said.

The union remains concerned about employees returning to classrooms before they are inoculated, and for students who could unwittingly contract the virus and spread it to their classmates. It has raised concerns about ventilation in aging buildings and whether the school system would provide masks for staffers and students.

Teachers have said that they have little trust that the school system will do what is necessary to make buildings safe. Some building were erected in the 19th century, and the school system has about $3.4 billion in deferred maintenance.

“We want to be able to trust that those things have been done, and that has not always been our experience when it comes to dealing with Chicago public schools, regrettably,” said Tara Stamps, an elementary school teacher who is working for the union.

She said she is particularly concerned that poor neighborhoods, already hit hard by the virus, will not get the sort of mitigation measures they need to keep teachers safe. “We know the city is not equitable and the resources that get disbursed in the city [are] not equitable.”

The new federal funding is meant to address some of these issues, though it’s unclear exactly how districts would use the money or whether it would arrive in time to make a difference this academic year. There are also fears that cash-strapped states, through budgetary sleight of hand, would divert the funding elsewhere.

Still, the $54 billion allocation is more than four times the $13.5 billion that K-12 education was previously given.

“There’s no way that Congress can pass $54 billion and it won’t help some schools open,” said Noelle Ellerson Ng, associate executive director for advocacy and governance at the School Superintendents Association, known as AASA.

In Chicago, for instance, officials anticipate receiving about $800 million from the relief package, and Jackson said it could help a return to in-person education.

“This crucial federal funding ensures our ability to support the critical resources needed to reopen classrooms,” she said in a statement. She said she would use the money to pay nurses and social workers and provide additional funding for the highest-need schools, among other things.

“Black and Brown families in Chicago need the option to send their children to school this academic year, and this funding relief is essential to the safe and supportive learning environments needed to mitigate learning loss and prevent long-term harm,” she said.

Ng thinks Biden also will make a difference, as the president-elect emphasizes helping schools to reopen rather than bullying them into it.

“He’s not Trump. That’s just a reality,” she said. “Any president who isn’t Trump would get a fresh bite at this push to reopen schools.”

But many teachers are profoundly frightened of going back, especially without a vaccination and given the surge of cases in recent weeks.

“I’m petrified,” said Tassie Zahner, a history teacher at Northwood High School in Silver Spring, Md. “I don’t want to get sick and die for my job.”

She emphasizes the successes of remote learning. She said some of her students are motivated to succeed, and some are not — just like in regular school. She doubts the data that finds little virus transmission inside schools.

Still, she said she would be willing to go back if she were offered a vaccine.

“I think that if you want teachers to feel safe enough to go back into the classroom, you want to reopen schools, (then) teachers need to be moved up on the list,” she said.

Other teachers say a vaccine may not be enough.

Terrence Martin, president of the Detroit Federation of Teachers, said some Black educators, in particular, remain suspicious of the vaccines and fear getting inoculated. The pandemic has taken a deep toll in the Black community in Detroit and elsewhere, and there’s a long history of mistreatment by the medical establishment.

“There are folks who just don’t trust the government, don’t trust vaccination and obviously for good reason,” Martin said.

In Los Angeles, a vaccine will not allow a return to school as long as community transmission rates remain high, said Austin Beutner, superintendent of the Los Angeles Unified School District, which serves nearly 600,000 students.

He said it will take a long time for everybody to get vaccinated and for the vaccination to take effect. He said he also worries that even vaccinated people can spread the virus.

“So, we are a long way from having students and staff in school,” he said.

At some point, he added, he expects students and employees will be required to get a coronavirus vaccine, just like they are required to take other vaccines.

“I think at the end of the day coronavirus vaccine will not be any different than those,” he said.