Major medical centers nationwide are trying to understand why some COVID-19 patients continue to have symptoms weeks and even months after having been diagnosed with the coronavirus.
Amy Watson, 47, is one of those patients. She's had a fever, she said, for more than 100 days.
"It's been maddening," said Watson, a preschool teacher in Portland, Oregon. Since mid-March, her temperature has crept up to 100 or 101 degrees almost daily by midafternoon.
She was diagnosed with COVID-19 in April, about a month after her symptoms — cough, congestion and extreme fatigue — began. Now, those symptoms have evolved into weeks of low-grade fever and a burning sensation under her skin.
Watson's illness was never severe enough to warrant hospitalization. Instead, her symptoms have lurked in the background, never fully resolving. Doctors have had few answers for her.
"My doctor has been very good at listening to me. She just doesn't have a lot of ideas as far as how to fix what's wrong," Watson said.
But there is a growing movement among health care providers to not only listen but also figure out ways to help such patients.
"Physicians should not be discounting the experience of individuals, especially in the case of a disease that we know next to nothing about," said David Putrino, a physical therapist and assistant professor at the Mount Sinai Health System in New York City.
"This is very real condition," he said.
Last week, the World Health Organization and the Centers for Disease Control and Prevention also acknowledged such reports and said they are working to better understand the recovery phase of the illness.
Putrino and colleagues at Mount Sinai have begun monitoring COVID-19 patients who experience a milder, long-lasting form of the virus at home.
"What we're trying to understand is what does this new syndrome look like?" Putrino said. "How might we manage it, and how might we help some of these people get back to a regular daily life?"
Dr. Jessica Dine, a lung doctor at Penn Medicine in Philadelphia, said she began noticing a subset of COVID-19 patients whose symptoms lingered long after their diagnoses thanks to a hospital program called COVID Watch, a texting service that does daily check-ins with COVID-19 patients at home.
Now Dine, who is also the director of the advance consultative pulmonary division at Penn Medicine, is working with those patients to better understand their illness.
Her team starts by ruling out obvious causes of the long-term symptoms.
"The first thing I do is make sure is there not something new going on, that we're not missing something," Dine said, such as a secondary infection, a complication of the virus or a side effect of treatment.
If Dine and her team are able to rule out other causes, they have two hypotheses for what's going on. The first is that it's possible that the virus is still somewhere in the body, undetectable through testing. The other is that the virus is gone from the body but patients are experiencing what's referred to as post-viral inflammatory syndrome, in which the body's immune system remains "revved up" even after the virus goes away.
"What we need is more research to explain where the symptoms are coming from," Dine said.
One theory is that the inflammation triggered by COVID-19 damages the autonomic nervous system, which affects functions we don't consciously think about, such as digestion, sweating, sleep, heart rate and blood pressure.
Dr. Mitchell Miglis, a neurologist at Stanford University, ascribes to this theory. He said it appears that for some people, "the body is still damaged" even when the virus is long gone.
"It can take a really long time to fully recover," he said, adding that it's too soon to know whether the condition will clear up eventually or whether the symptoms will continue as a chronic disease.
Miglis and his team at Stanford have begun developing a registry to track such long-term COVID-19 patients over time.
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There is no specific therapy for the kind of long-term inflammation doctors suspect may be causing problems, other than medications to ease symptoms such as cough or fever. And Dine said there is no good treatment for one of the most debilitating manifestations of COVID-19: extreme fatigue.
Putrino, of Mount Sinai, has begun to develop a kind of protocol for people whose symptoms, like Watson's, have lingered for weeks and weeks.
Plans are individualized, but they usually involve very specific ways of training the body to compensate for unconscious functions. Many patients are given exercise plans, sleep regimens and nutrition guidelines.
Mount Sinai dietitian Adena Neglia is working with Putrino on the nutrition aspect of the protocol. "During times of stress and anxiety, some people may turn to food, while others turn away from food," Neglia said, adding that nourishment is important to support a healthy immune system.
Experts elsewhere echo the guidance to focus on behaviors that will keep people as healthy as possible. "Eat right and stay hydrated, especially during this time with increasing summer heat," said Dr. Gary LeRoy, president of the American Academy of Family Physicians.
LeRoy, a practicing physician at the East Dayton Health Clinic in Dayton, Ohio, said he hasn't treated any COVID-19 patients with long-term symptoms. But he has counseled some who said they struggled with lingering fatigue about ways to get their energy back.
Watson has found bits of relief from her symptoms with rest, "which is hard, because I'm a go-go-go kind of person," she said.
She wants other COVID-19 patients with lingering symptoms to know they're not alone.
"You're not crazy. These symptoms are real," Watson said. "If you find a medical professional is not listening to you, find a different one."