Kate Porter has had a fever nearly every day for 50 days. She can't shake the extreme exhaustion that hit when she became infected with the coronavirus nearly two months ago.
The longevity of her symptoms are unlike anything she's ever experienced. "I know it sounds crazy," Porter said, "but is this permanent?"
Since her diagnosis, Porter, 35, has been in her Beverly, Massachusetts, home with her 12-year-old daughter, Adria, who also had symptoms of COVID-19.
Neither has underlying health conditions that would suggest a complicated or drawn-out recovery from the virus, and neither has had to be hospitalized.
According to data collected by Johns Hopkins, more than 180,000 people in the U.S. have recovered from COVID-19. The Centers for Disease Control and Prevention considers a person recovered if three days have passed since a fever broke without the assistance of medication, and respiratory symptoms, such as cough or shortness of breath, have improved. Negative tests can also signal recovery, but tests can be inaccurate.
After an initial positive COVID-19 test, Porter has since tested negative for the virus, yet symptoms persist.
"I'll feel great one afternoon and think, 'I'm going to read, I'm going to do laundry,'" Porter told NBC News. Inevitably, the fever and fatigue return.
It happens repeatedly, Porter said. "It's like a mind game."
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Andrew Dumont, 32, of Seattle, has also tested negative for the virus after a previous positive COVID-19 test. Two months since first falling ill, Dumont still suffers from numbness in his limbs and shortness of breath -- prompting two visits to the emergency room twice in the past week.
CT scans and lung x-rays showed no additional infections.
"It's really scary, because you're just kind of left at home by yourself essentially trying to treat it," Dumont said.
Intense outpatient management
COVID-19 patients who are not sick enough to be hospitalized have little guidance on how to recover. There is no specific drug or treatment, other than rest, fluids and fever-reducing medicine such as Tylenol.
But because the virus can smolder in the body for days or weeks before potentially worsening, some physicians are increasing their vigilance for those recovering at home, alone.
"We do frequent telephone calls, checking in and telling patients what to watch out for," Dr. Lara Hall, clinical lead for the Cambridge Health Alliance Respiratory Clinic near Boston. "The thing we really worry about is shortness of breath."
Experts say trouble breathing is a sign that COVID-19 may be wreaking havoc in the body, and usually requires an emergency response.
Hall estimates her clinic has seen about 2,400 patients with symptoms of the coronavirus since it opened nearly seven weeks ago. About 70 percent of those patients have tested positive.
Some patients may require more frequent check-ins. "If someone's over 65 and they have diabetes or high blood pressure or heart disease or obesity, chronic lung disease," Hall said, "those are people in a high risk category that we're calling every day."
"We call this intense outpatient management," she said. Some patients may need to be seen again at Hall's clinic, while others may be urged to seek care at an emergency room.
'I dread going to sleep'
Many COVID-19 patients recovering at home recount similar anecdotes of how the virus acts each day and night.
Mornings tend to begin normally, but as the day progresses, viral symptoms creep in "like clockwork," Porter said.
Temperatures begin to rise. Cognition becomes hazy. Porter describes it as a "weird forgetfulness" as she struggles to find words.
"Nighttime is when things start to flare up a bit more, and I just get nervous."
As night falls, fear takes hold. Despite debilitating exhaustion and fatigue, many patients are unable to get a good night's sleep.
"Honestly, I dread going to sleep," Porter said. She frequently wakes up during the night with her whole body shaking, as if she's been exposed to freezing temperatures. After a subsequent fitful rest, she often wakes up with her hair, sheets and clothes drenched in sweat.
The ongoing symptoms make Porter and other patients worry they've developed a secondary infection. However, subsequent COVID-19 tests have been negative, and other diagnostic screenings have been unable to uncover additional problems.
"I think I'm in the clear, but I'm not sure," Porter said, as she continues to log daily fevers. "It feels never-ending. I am at a loss."
Dumont, too, has suffered sleepless nights because of COVID-19.
"My breathing has been so bad that last week there were three nights where I couldn't even lay down," he said. "I stayed awake without any ability to sleep."
Doctors become patients
Even doctors with a keen understanding of how viruses typically act understand recovering patients' concerns.
"As a physician, I know what can happen," Dr. Michael Saag, a renowned infectious disease expert at the University of Alabama at Birmingham, said. Saag was diagnosed with COVID-19 in March and described the illness as a "horror" that included fever, muscle aches, fatigue and difficulty thinking.
"I would sit awake, counting the minutes until morning almost, wondering if my breathing was going to get worse and I'd end up on a ventilator," he said.
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Dr. Buddy Creech, an infectious disease expert and director of the Vanderbilt Vaccine Research Program at Vanderbilt University Medical Center in Nashville, expressed similar fears after he, too, was diagnosed with COVID-19.
"I was just kind of watching it happen, documenting my symptoms," Creech said. "It was legitimately terrifying."
Creech's wife and three children were also diagnosed with the illness, with symptoms that varied in degree. None had to be hospitalized, and the five family members stuck it out together at first, resting and staying hydrated.
"We had flu-like illness with chills, muscle aches, headaches, but when I would take Motrin or Tylenol, I would feel great," Creech recalled. "We had an epic game of Monopoly going on."
The family started to recover after about a week. But Creech's apparent recovery did not last.
"One of my colleagues warned me that the second week can go sideways," Creech said. Indeed, on day seven, he developed a more substantial cough and a fever that lasted weeks.
"I felt like I was having this inflammatory response that I simply couldn't control," he said.
Patients like Porter and Dumont, who have had long-term symptoms, understand the value of sharing their stories.
"I was desperate for someone to tell me I'm not crazy," Porter said. "It's scary to go through this for so long when there's so many unknowns about the virus."
Dumont shared his COVID-19 symptoms on Twitter, and said he's since received hundreds of messages on the social media site from other patients with similar stories.
'We fall into the category of not critical and dying, but not asymptomatic," Dumont said.
"That's a very lonely, unclear place to be."