Allison Mayo had contracted COVID-19 but was still working from home in September when, on a conference call, she stopped making sense.

She couldn’t find the words to finish a sentence. Then she noticed her hands turned gray.

When diagnosed, Mayo got a device to measure her blood oxygen. The reading that September day was 66%. Anything under 90% or so is considered too low.

Mayo raced to the emergency room, expecting to get a chest X-ray before coming home.

Little did she know she’d spend four days at the hospital in respiratory failure and fighting COVID-caused pneumonia in both lungs, despite not feeling terribly ill.

And she definitely didn’t expect that seven months later, she’d still be fighting.

Mayo, 50, is one of an untold number of Hampton Roads residents suffering from so-called “long-haul COVID” or “long COVID.”

They contract COVID-19, and whether they had severe symptoms initially, they either remain sick or the symptoms boomerang after the victims have seemingly recovered. A wide range of symptoms can plague them for months on end, with little treatment or established research to turn to.

“This long haul thing is real, and it really does affect you,” Mayo said.

The rise and fall of new COVID-19 cases are tracked and closely watched by many. But the tail end of those spikes — people dealing with the ramifications for months afterward — don’t appear in the statistics. The latest medical literature suggests that long COVID happens in at least a tenth, and up to a third, of all coronavirus cases.

Everyone is still learning about this coronavirus itself, let alone its mysterious, long-lasting complications.

But doctors around Hampton Roads are starting to take notice.

Before getting the coronavirus, Mayo said she didn’t take it too seriously.

She works from her Virginia Beach home for a medical device company and followed all the state’s pandemic rules, but “I thought it was like the flu until I got it.”

In September, James Madison University sent students home, and Mayo’s husband picked up their freshman son and his roommate. The day after they returned home, they felt sick and tested positive for the virus. It soon spread to the rest of the house, including to Mayo and her teenage daughter — both tested positive at a local pharmacy.

Mayo had plenty of symptoms: vomiting, chills, fever, headache and leg pains. But she worked throughout, taking nap breaks between calls.

After about 10 days of the illness, her blood oxygen level dropped abruptly, sending her to the ER at Sentara Virginia Beach General Hospital.

Mayo said she failed several tests, and was surprised to learn she’d gone into respiratory distress at home without even knowing it. “That pulse oximeter saved my life,” she said.

She was hospitalized for staying for several days, and received a convalescent plasma donation that significantly helped. Plasma therapy uses blood from recovered COVID patients to give recipients antibodies against the virus.

“I was a 49-year-old healthy person and when I left the hospital I left on oxygen and tons of medication,” she said.

It took a few weeks for Mayo to realize that this illness wasn’t going anywhere soon.

Her taste, which had been off — a hallmark sign of the coronavirus — stayed that way. Fatigue ailed her.

And perhaps more scary than anything else, she experienced memory loss and brain fog.

“It’s kind of like a brain injury,” she said. “I almost felt like I had dementia.”

Mayo had trouble processing emails longer than a few sentences. To this day, she writes everything down so she won’t forget, carrying notepads everywhere. She’s plagued by high blood pressure, which she never had. Through February, she had to use oxygen. It seemed like there were always new problems.

“It was like the gift that kept on giving, in a bad way,” she said.

Eventually, Mayo connected with a new post-COVID clinic based at the Sentara Heart Hospital in Norfolk run by Dr. Xian Qiao, a pulmonary critical care specialist with Sentara.

“Once I found them it was such a sigh of relief,” Mayo said.

Long-haulers can feel very alone, she said. Busy primary care doctors can fail to see a pattern or even misattribute certain symptoms as psychological. Qiao had seen other long-haulers, so when Mayo reported what she was feeling, he was able to relay that others had felt the same.

Mayo even felt oddly relieved having tests come back positive, including lung scarring, because “it validated what my symptoms were.” These days, Mayo said her fatigue has improved but she still has nerve and joint pain. She invested in a treadmill desk for work because sitting is painful.

She’s also found comfort in joining Facebook groups for long-haulers, listening to other people’s experiences that mimic her own.

“Now I’m basically dealing with what COVID left behind,” she said.

A few months into the pandemic, Qiao and colleagues realized many patients they were discharging from local hospitals would stay sick out in the community. They thought, “there may be a way to help them and learn more about the disease process itself,” he said.

The result: the post-COVID clinic. They started with only patients who had been hospitalized with COVID. But they’re also “seeing more and more patients who were not necessarily hospitalized but have prolonged symptoms even though they weren’t bad initially,” Qiao said.

The estimate of about 10% of COVID patients experiencing symptoms for longer could be an undercount, he said. Even if it’s not, “that’s a large absolute number on the community.”

Symptoms he sees include fatigue, shortness of breath despite diagnostic tests not turning up much and unexplained fast heartbeats. Then there’s the brain fog. His patients often walk into rooms without remembering what they were doing and had to make adjustments to their high-functioning jobs. “That can be quite life-altering,” he said.

Qiao helps patients figure out which symptoms are linked to problems that can be treated, such as an irregular heartbeat from atrial fibrillation. He tries not to order a host of tests on every patient, he added, because he knows that can easily run up a bill and not yield much.

“The challenge is this is not your everyday diagnosis,” he said. “There’s no magic pill for this. We have to figure out what we’re dealing with.”

Adding to the puzzle, some long-haulers have recently reported that their symptoms eased or went away after getting a COVID-19 vaccine. But more research is needed to confirm a connection.

There will be an ongoing discussion over the next months and years, even when the immediate pandemic has ended, over how to holistically treat these patients, added Dr. Steven Pearman, Sentara’s vice president of medical operations for primary care.

“This is when you have to look at the whole person,” Pearman said. “These life-altering neurological and physical symptoms have behavioral health impacts as well. It’s a combination of the psychological impact of having your life turned upside down, and rehab in terms of” physical therapy and so on.

At Bon Secours, local physicians have started seeing a spike in long-haulers coming through a cardiopulmonary rehab program. Dr. Vandana Patel, a pulmonologist, and her husband, Dr. Apurva Patel, a cardiologist, have seen hundreds of patients with lasting symptoms.

Aside from the known physical symptoms, dealing with a prolonged illness such as long-haul COVID can produce mental and emotional symptoms, too: Depression, anxiety, a sense of isolation and mood swings are not uncommon, especially for those nearly a year out from an initial diagnosis, Vandana Patel said.

There are two general categories of her patients, she said: those with mainly a cough or wheezing where treatment like inhalers can cause symptoms to improve — and those with symptoms such as chronic fatigue and brain fog that have no clear treatment options.

She’s filled out more medical leave and long-term disability forms than ever before.

“Going back to work full time has been an issue for a lot of these people,” she said. “I’ve been practicing for 35 years now. I’ve never seen a virus like this.”

In the rehab program, the Patels encourage their patients to do small exercises to regain their strength, including modest cardio and muscle strengthening. The relief of connecting with others going through the same thing is equally beneficial, they said.

Apurva Patel said he’d like to see support groups for long-haulers in Hampton Roads.

“I think that’s probably a key community need,” he said. Long-term, “we also need employers’ empathy. A lot of these people might not be able to return to work 100%.”

The Patels’ experience with long COVID hasn’t just come from patients.

Their nephew, 31-year-old Ankur Patel, has strugged with long-lasting symptoms since he first got the virus in early February. He and his parents, with whom he’s staying in Suffolk, were infected that month, he said.

Since then, his parents have mostly recovered but he has run the gamut of symptoms: fatigue, nausea, headaches, digestive issues and shortness of breath. At its worst, he couldn’t stand on his own and “almost felt sedated constantly.” He couldn’t walk for five minutes without getting dizzy.

Ankur Patel said he didn’t need to be hospitalized, but has been on rotating prescriptions. He’s been doing small rehab exercises when he can, as advised by his aunt and uncle.

It’s been a jarring whiplash for a young, healthy person who spent much of his time biking, kayaking and mountain climbing.

Long COVID came as a surprise. After his initial symptoms, he felt consistently better. Then, overnight, he felt back to Day 1. These flare-ups have repeated, with no particular rhyme or reason. They can include waking up gasping for air and profusely sweating. Sometimes he’s scared to go to sleep.

The disease breeds an anxiety that makes it hard to go about your day, he said.

“This is one of the most collectively, mentally and physically, breaking things I’ve gone through,” Patel said. “It takes a pretty heavy toll.”

He encourages everyone who can to get a vaccine — even the young and healthy who may feel more safe.

“I thought I was totally fine, that I wouldn’t have any issue tackling the virus, and obviously it’s something that has lingered with me.”

Katherine Hafner, 757-222-5208, katherine.hafner@pilotonline.com