Truth is we are no closer to having a biomarker for fatigue. There is no particular reason why the normal fatigue that people get from working hard has anything to do with the chronic fatigue that ME/CFS and other chronic diseases face. ME/CFS is unique in its payback where a sufferers pushes through the fatigue and ends up with symptoms worsening and new symptoms 12-72 hours later that can last a day to the rest of their lives. That isn't just fatigue and the UK doctors have been trying to make ME/CFS all about fatigue since the 1980s and it caused immense harm. It actually has about 280 symptoms, of which fatigue is just one and not even the most debilitating or important one.
Long Covid is really not new. It is virtually indistinguishable from the condition long known in the medical lexicon as post-infectious syndrome or myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Although some have recognized and studied their similarities, it seems no one has made the simplifying observation that they are essentially the same condition.[1]
Symptom wise and quite a lot of the biology they definitely appear similar. The problem is the genetics studies show some overlap, about 80 combined SNPs for ME/CFS out of 270 and out of around 150 for Long Covid.
There is more to it than just different genetic mappings because while both conditions share mitochondria differences which compartments are different. Depending on how deep you dig into the biology they appear the same or quite different and a number of multiple point blood, urine and saliva tests can distinguish the diseases from each other.
I think at this point its more accurate to say they are overlapping conditions, they have similarities but they are different conditions. Sister diseases much in the same way there is overlap in Fibromylgia and Gulf War syndrome with ME/CFS and each other. Long Covid is another post infection Neurological and immune disease with unknown biomarker/core pathology. There are clearly a lot of measurable changes that are dysfunctional so its every bit as real biological disease as the others. What they definitely share is a high amount of debilitation, severe disability and patient reduction in quality of life on the same set of 280 symptoms in a very similar patter of prevalence.
Its also now a disease with very little research funding world wide as well so the situation is unlikely to improve for the 400m+ sufferers world wide.
I really don't understand this comment? Its quite commonly known that this is the same/related?
Your 'source' is btw. from 2023 and as far as i understand it, the main issue is, that due to covid, a lot more people got it but because it was already ignored or played down before, it still is and the people in need just don't get help.
Covid apparently triggered it in more people than before.
I also have the feeling that someone else posted this missconception a few weeks ago on hn. Or was that you too?
Not sure about the ME/CFS thing, but "post-infectious syndrome" is literally what its name says it is which makes it a larger category that "long covid" would taxonomize under.
In the limit, there's no difference between a scientific fact and an unfalsified hypothesis. I'm not aware of anyone falsifying this one, and it's over five years old, so I'm going to say "scientific fact".
I'll put it another way: long COVID has been studied quite a lot over the past 5 years, and I'm not aware of anyone being able to distinguish it from ME/CFS (except by definition). People appear to have stopped trying to draw a distinction, by and large. See https://doi.org/10.3390/biomedicines13112797 for a Nov 2025 literature review, which basically says "except for long COVID being caused by SARS-CoV-2, it's very difficult to tell long COVID and ME/CFS apart" in excruciating detail.
(Technically, long COVID is a broader diagnosis, encompassing some long-term conditions caused by a COVID-19 infection that are distinct from ME/CFS, but I consider that a "by definition" distinction rather than anything real.)
[1]: https://www.statnews.com/2023/09/14/long-covid-me-cfs-myalgi...
There is more to it than just different genetic mappings because while both conditions share mitochondria differences which compartments are different. Depending on how deep you dig into the biology they appear the same or quite different and a number of multiple point blood, urine and saliva tests can distinguish the diseases from each other.
I think at this point its more accurate to say they are overlapping conditions, they have similarities but they are different conditions. Sister diseases much in the same way there is overlap in Fibromylgia and Gulf War syndrome with ME/CFS and each other. Long Covid is another post infection Neurological and immune disease with unknown biomarker/core pathology. There are clearly a lot of measurable changes that are dysfunctional so its every bit as real biological disease as the others. What they definitely share is a high amount of debilitation, severe disability and patient reduction in quality of life on the same set of 280 symptoms in a very similar patter of prevalence.
Its also now a disease with very little research funding world wide as well so the situation is unlikely to improve for the 400m+ sufferers world wide.
Your 'source' is btw. from 2023 and as far as i understand it, the main issue is, that due to covid, a lot more people got it but because it was already ignored or played down before, it still is and the people in need just don't get help.
Covid apparently triggered it in more people than before.
I also have the feeling that someone else posted this missconception a few weeks ago on hn. Or was that you too?
Your statement can also be applied to the inverse of the hypothesis, after all.
(Technically, long COVID is a broader diagnosis, encompassing some long-term conditions caused by a COVID-19 infection that are distinct from ME/CFS, but I consider that a "by definition" distinction rather than anything real.)