They may have survived a pandemic, but survivors of the coronavirus are still fighting.

The lasting damage of COVID-19 is only just now becoming clear to doctors — and to the patients who are adapting to life on the other side. Some, such as six-time Tony nominee Danny Burstein, say the long-term impacts of the disease that almost killed him will be difficult to grapple with.

Burstein, who was starring in “Moulin Rouge: The Musical!” on Broadway before the city shut down, built strong lungs by singing and dancing onstage for 40 years.

But now, weeks after recovering from the coronavirus, just taking the garbage down two flights of stairs has him completely winded.

“Sometimes I’m having conversations and I can’t get enough air, that’s the toughest part,” Burstein, 55, tells The Post. “It’s frustrating. It’s been a very slow recovery. For the most part, the symptoms are gone, but what remains is the damage that was done to my lungs.”

Will they ever recover?

Tens of thousands of patients have already recovered from COVID-19. But the long-term effects of the disease are only just beginning to become apparent. Burstein and many other patients are still experiencing breathing and other problems weeks after they began feeling better, for example.

“One of the biggest questions . . . is [whether] these patients will recover fully, or if there will be chronic lung damage from this virus,” says Mina Rafik Makaryus, MD, a pulmonologist at Northwell Health.

Makaryus says it is “overwhelming” to think about how many patients there could be with long-term lung problems.

“There are not enough pulmonologists in the community to handle this potential number of chronic lung injuries,” he adds.

There’s only a little data on recovered patients so far — even the earliest Chinese COVID-19 diagnoses are only 3 months old. But in a small study of 34 patients, researchers found that COVID-19 affected metabolism and caused other “physiological changes.” Another early study in China found heart damage in 12% of patients who did not have respiratory issues.

“There just isn’t enough data yet,” Makaryus tells The Post. “You worry especially for patients who had to go on life support and what those long-term effects will be.”

For Shaun Khubchandani, 30, recovering from the coronavirus was not easy. Weeks after his diagnosis, breathing still made his lungs feel “on fire.” Although the Soho resident says he is now “fully recovered,” four weeks after his positive COVID-19 test, he can’t stop wondering if there will be any lingering lung damage.

“I had a long recovery,” Khubchandani tells The Post. “For my age, I was not expecting this at all. This was not mild flu.”

He had symptoms for three weeks straight. But after those subsided and he was feeling better, “it felt like my lungs were on fire,” he says. “I couldn’t take a deep breath. That’s when I started getting worried.”

Recovery is a false alarm

Khubchandani also says the virus is a sneaky one: It “tricked” him numerous times into thinking he was better, even after two weeks.

“I had a couple of false alarms, where I felt like I’d totally recovered, and then the next day a fever came back,” he says.

“Towards the end, when I started having chest pains, I had concerns that maybe I’ve damaged my lungs or that I’ll develop some long-term issues but I got a chest X-ray and it looks clear.”

Burstein, who documented his diagnosis and hospital stay in vivid detail for The Hollywood Reporter, is familiar with the “false alarms” that COVID-19 brings.

“It would be as if it was going away, and then you’d have these weird flare-ups,” he tells The Post. “One day it’s crazy sweats and headache and then it’s backache, when one goes away, one comes back. It’s like fingernails sliding down your back, clinging on.”

Burstein and Khubchandani both used a spirometer to help improve their breathing, and Burstein says he also blows up a balloon “every hour” to strengthen his lungs on the advice of his doctor.

“Patients are telling me that their breathing is getting better overall,” Makaryus says. “But I have seen a number of patients who still require oxygen weeks after diagnosis.”

Two steps forward, one step back

“You also worry about the long-term psychiatric implications,” Makaryus says. “One of the things that makes this more difficult is that it’s a lonely disease for both patients and family.”

Survivors are mostly forced to recover alone, for fear of spreading the disease even further. And if they were attached to a ventilator, the experience may cause some post-traumatic stress, doctors say.

For Brianna Cohen, an actress who lives in Hoboken, New Jersey, the symptoms the second two weeks were worse than the first.

“The symptoms kept changing,” Cohen, 32, tells The Post. “It was always two steps forward, one step back.”

More than five weeks after first feeling ill and a month post-positive test, she is still experiencing some lingering symptoms, such as lung pain — “My lungs feel like they are on fire” — and anxiety.

“At one point, about three weeks post-COVID [diagnosis], my blood pressure was through the roof and my heart rate was [extremely high],” she says. “I got a lung X-ray and an EKG and everything was fine. They gave me a small amount of [anxiety] medicine and now my heart rate is fine.”

Burstein says the harrowing experience made him reckon with his mortality in a profound way. After 20 hours in the ER and once his test came back positive for COVID-19, hospital personnel told him that they were sending him to the COVID-19 unit.

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“Right after they said that, they asked me if I was an organ donor,” Burstein says. “It was a sobering lesson.”