Some answers are coming in on long Covid disease

As seen in other long COVID studies, the problem wasn't related to how their lungs or heart were functioning. Instead, something was making it hard for the muscle to take up the oxygen in the blood.

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"As opposed to what's been sold to patients over the last few decades, that symptoms such as extreme fatigue and exertional malaise are psychological or physical conditioning issues," he says. "Physical exertion does harm to the bodies of people with these illnesses."

His general guidance is to avoid exercise if you have post-exertional malaise and instead practice "energy conservation."

At his clinic, Putrino prescribes what's called "autonomic rehabilitation" for these patients.

  NPR

Fauci pushes for more long-covid research

Dr Anthony Fauci, America’s top infectious disease expert, has warned against prematurely declaring victory over the pandemic, not only due to short-term needs but because long Covid represents an “insidious” public health emergency for millions of people.

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The World Health Organization estimates that between 10% and 20% of Covid-19 survivors have been left with mid- and long-term symptoms including breathlessness, fatigue and cognitive dysfunction. Fauci noted estimates that anywhere from 7.5 million to 23 million Americans have developed long Covid and roughly 1 million people are out of the workforce at any given time.

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Fauci said: “One of the unfortunate, challenging and frustrating parts about it is that there are so many elements of it that don’t fit into a known or recognisable pathogenic process so, if someone is severely fatigued where they can barely do any work, there is a laboratory test or an X-ray or a CT scan or an MRI that points to something and says, ‘Well, look, there’s inflammation here and that’s the reason for the fatigue.’

“We don’t know what the mechanisms of brain fog are. How come someone who is very sharp intellectually and very energetic all of a sudden can’t concentrate for more than half an hour on anything? And how come people who are polished athletes no longer have any exercise tolerance?”

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“The question we get asked all the time is: what can we do about it? As a physician and a scientist all my professional life, you don’t really know what to do about something until you know what the lesion is and we don’t know what the lesion is yet. That’s the problem.”

Experts are trying to solve the riddle. Both the National Institutes of Health (NIH), where Fauci is director of the National Institute of Allergy and Infectious Diseases (NIAD), and the Centers for Disease Control and Prevention (CDC) are carrying out major studies.

  Guardian

Long Covid

So far there are more theories than clear answers for what's going on, and there is good reason to think the varied constellation of symptoms could have different causes in different people. Maybe the virus is still hiding in the body somewhere, in some, directly damaging nerves or other parts of the body. Maybe the chronic presence of the virus, or remnants of the virus, keeps the immune system kind of simmering at a low boil, causing the symptoms. Maybe the virus is gone, but left the immune system out of whack, so it's now attacking the body. Or maybe there's another cause.

"It's still early days. But we believe that long COVID is not caused by one thing. That there are multiple diseases that are happening," says Akiko Iwasaki, a professor of immunobiology at Yale University who is also studying long COVID.

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"We are finding elevated cytokines in long-COVID patients and we're trying to decode what those cytokines mean. We're also seeing some distinct auto-antibody reactivity and are trying to find out what those antibodies are doing and whether they are causing harm," Iwasaki says.

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Yet another clue found in one subgroup of patients is an unusual pattern of activity by key immune system cells, such as as T-cells, which may support the idea that the virus is hiding in the body.

"That's a signature or pattern which could be consistent with a low-level, but persistent, infection in the long-COVID syndrome patient," says Dr. Igor Koralnik at Northwestern Feinberg School of Medicine.

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Yet another clue found in one subgroup of patients is an unusual pattern of activity by key immune system cells, such as as T-cells, which may support the idea that the virus is hiding in the body.

"That's a signature or pattern which could be consistent with a low-level, but persistent, infection in the long-COVID syndrome patient," says Dr. Igor Koralnik at Northwestern Feinberg School of Medicine.

  NPR

...but hey, do what you want...you will anyway.