South River, New Jersey(CNN) Fifteen years ago, Annette Lang left a Wall Street career for a new start. She was finally ready to follow her passion -- teaching. It brought her back home to New Jersey, where she got a job as a fifth-grade teacher at South River Elementary School.
Two years ago, Lang began teaching middle school math. She was having a blast.
"I just felt like I was hitting my stride there," she told CNN. "I was really excited about coming in and really blowing the walls off."
Lang, now 61, was planning to stay in the classroom, with no thought of early retirement.
"I was going to go at least four more years, until I turned 65," she said. "And possibly after."
The coronavirus pandemic changed everything.
"I had my first panic attack in 60 years of my life. I was worried about getting sick, I was also worried about bringing something home," Lang said, explaining her husband is older than her and has a pre-existing condition, making him more vulnerable if exposed to Covid-19.
Lang said she was concerned about the school building itself.
"When you look at the CDC guidelines, the big thing that they kept saying about schools is open the windows, open the windows," she said. "Windows in my building don't open."
Ultimately, Lang left her job in December, after what she called a "very difficult" decision.
"Being a teacher is not just a job ... I am a teacher, it's part of our persona."
Lang is not alone. Teacher retirements are up in several parts of the country. Michigan saw a 44% spike from August to February compared to the previous year, while one of the largest districts in California, Long Beach Unified, reported a 35% increase in teacher leaves of absence to the Learning Policy Institute (LPI) at Stanford University.
Linda Darling-Hammond, LPI president and an adviser to the Biden transition, said: "Teacher attrition is very high in the United States. It's twice as high as it is in places like Canada or Finland or Singapore."
She said teaching had been a neglected profession in the US for a long time, and while the trend of increasing retirements began a few years ago, she worries it will be exacerbated by the pandemic.
"There's fear about the safety of coming back in person, particularly in places where the mitigation strategies have not been well used in schools and where things are opening up," Darling-Hammond said.
"People are getting rid of mask mandates and things like that sooner than everyone is vaccinated. So I think those are the things that are causing exhaustion and the fear that is driving a lot of teachers out."
It was that fear that was behind Jaime Acosta leaving his job last October after seven years as a teacher in Houston.
"I didn't feel safe. And I am pretty sure I can speak for a lot of my colleagues, we did not feel safe going back into the classroom."
Acosta also struggled with exhaustion throughout virtual teaching, he told CNN.
"Not only are you in new territory, but you're dealing with technology," he said.
"You're still required to do all of the things that come with teaching a diverse group of kids and you're at home by yourself. Sometimes, half of my class was not present. What am I supposed to do about that?
"At 3:30, after school was done, my responsibility was to call parents and figure out what's going on. It just became way too much, way too much."
Stress, exacerbated by Covid-19, was the most common reason for early teacher retirement in 2020, according to a study by the Rand Corporation.
Another factor is pay. The average salary for a public school teacher is about $61,000, according to Darling-Hammond.
"Teaching pays about 20 or 30% less than other fields that often require similar training in the United States," she said. "Many people want to teach out of the altruism and commitment that they feel, but they can't afford to teach."
President Biden's Covid-19 rescue plan allocates $129 billion for K-12 funding, which includes hiring more teachers.
But that may prove to be difficult, with fewer college students pursuing careers in education. A survey by the American Association of Colleges for Teacher Education had nearly 20% of respondents reporting a significant drop in new undergraduate enrollment in teaching programs for fall 2020.
Experts such as Darling-Hammond say reversing that trend begins with more teacher support.
"Build the social services around them so that they don't have to become social workers and counselors and everything," she said.
"We need to conceptualize a very supportive school environment that is going to be very different than the environment that many schools had pre-pandemic."
In Houston, Acosta has been working at a local bakery for the past six months, but he still misses teaching.
"I'm always going to be a teacher," he said. Even though I quit because of all the problems that were occurring and the Covid situation, I'm still a teacher, and I hope to go back one of these days."
But he's wanting things to change first.
"We, as teachers, are given way too much," he said. "I see that more in the public education system, specifically in Title 1 schools and poorer schools with less resources -- you have to take on and put on so many other hats to be able to do your job."
In New Jersey, Lang's teaching days may be over, but she hasn't stopped thinking about her students.
"I absolutely miss the kids," she said. "I'm a big New England Patriots fan and they all know that. And they would have been all over me about Tom Brady and Tampa Bay. So I miss being around them. I also I miss my coworkers. I mean, they were my family."