Long story short, we still have a lot to learn about long COVID-19.
But it is a real phenomenon with real long-term health effects for people recovering from coronavirus infections. And diagnosing and managing it can get tricky, as some symptoms of long COVID-19 overlap with those of other conditions – and what many people have as they recover from any challenging stay in the ICU.
Risk factors remain largely unknown as well: What makes one person more likely to have symptoms like fatigue, “brain fog,” or headaches versus someone else? Researchers are just starting to offer some intriguing answers, but the evidence is preliminary at this point, experts said at a media briefing sponsored by the Infectious Diseases Society of America.
Unanswered questions include: Does an autoimmune reaction drive long COVID? Does the coronavirus linger in reservoirs within the body and reactivate later? What protection against long COVID do vaccines and treatments offer, if any?
To get a handle on these and other questions, nailing down a standard definition of long COVID would be a good start.
“Studies so far have used different definitions of long COVID,” Nahid Bhadelia, MD, founding director of the Boston University Center for Emerging Infectious Diseases Policy and Research, said during the briefing.
Fatigue is the most commonly symptom of long COVID in research so far, said Dr. Bhadelia, who is also an associate professor of medicine at Boston University.
“What’s difficult in this situation is it’s been 2 years in a global pandemic. We’re all fatigued. How do you tease this apart?” she asked.
Other common symptoms are a hard time thinking quickly – also known as “brain fog” – and the feeling that, despite normal oxygen levels, breathing is difficult, said Kathleen Bell, MD.
Headache, joint and muscle pain, and persistent loss of smell and taste are also widely reported, said Dr. Bell, a professor and chair of the department of physical medicine and rehabilitation at the University of Texas Southwestern Medical Center in Dallas.
Not all the symptoms are physical either.
“Pretty prominent things that we’re seeing are very high levels of anxiety, depression, and insomnia,” Dr. Bell said. These “actually seem to be associated independently with the virus as opposed to just being a completely reactive component.”
More research will be needed to distinguish the causes of these conditions.
A difficult diagnosis
the experts said.
“We are starting to see some interesting features of inaccurate attributions to COVID, both on the part of perhaps the person with long COVID symptoms and health care providers,” Dr. Bell said.“It’s sometimes a little difficult to sort it out.”
Dr. Bell said she was not suggesting misdiagnoses are common, “but it is difficult for physicians that don’t see a lot of people with long COVID.”
The advice is to consider other conditions. “You can have both a long COVID syndrome and other syndromes as well,” she said. “As one of my teachers used to say: ‘You can have both ticks and fleas.’ ”