I hope someone will be able to point me to studies that have documented the resolution of (ME/CFS-like) long COVID at regular intervals during the first year and beyond. A bit like this from the Dubbo study by Hickie et al. 2006 https://pmc.ncbi.nlm.nih.gov/articles/PMC1569956/: I know I have read some but I haven't retained which studies they are in, so would appreciate help!
Hey, @Karen Kirke ! I'm not aware of such studies of the top of my head. There are many such studies on Long-Covid in general (some of which also have control groups and then there's also those comparing Covid to other infections) but when it comes to ME/CFS-like Long-Covid things are not as clear. There are of course studies that assess PEM and some other ME/CFS symptoms longitudinally (Patient-Led has done some work on this for instance in Characterizing long COVID in an international cohort: 7 months of symptoms and their impact), but it isn't always quite clear what ME/CFS-like long Covid then looks like or what it means and whether one can just "symptom count" ones way to ME/CFS using such studies. Presumably post-ICU syndrome might also look quite similar for a number of weeks at least, but is probably rather distinct in most cases. I know of some studies that give an indication on how things may roughly look like (for instance Long-term symptom severity and clinical biomarkers in post-COVID-19/chronic fatigue syndrome: results from a prospective observational cohort) but nothing too comparable for what you're looking for. There was very recently a risk-analysis for Long-Covid/ME/CFS titled The rising cost of Long COVID and ME/CFS in Germany, 2025, ME/CFS Research Foundation. Whilst it is a model, the authors might be able to tell you which data they based their model on.
Just from a quick Google Scholar search of 'long covid prevalence followup "24 months"'. I didn't read these in detail and they mostly seem to be about long COVID in general, but in case it's helpful: Determinants of the onset and prognosis of the post-COVID-19 condition: a 2-year prospective observational cohort study (2023, The Lancet Regional Health) Recovery and symptom trajectories up to two years after SARS-CoV-2 infection: population based, longitudinal cohort study (2023, BMJ) Epidemiology of post-COVID conditions beyond 1 year: a cross-sectional study (2023, Public Health) Symptom burden and post-COVID-19 syndrome 24 months following SARS-CoV-2 infection: Longitudinal population-based study (2025, Journal of Infection) Characteristics and Prevalence of Sequelae after COVID-19: A Longitudinal Cohort Study (2024, Infections & Chemotherapy)
I'm not interested in people who were in ICU and have organ damage or who only have loss of taste or smell or breathing issues. I'm interested in people who have something that looks like ME/CFS, so with fatigue, PEM, exercise intolerance, cognitive dysfunction etc as prominent symptoms.
Thank you for clarifying. I think you’re going to have a hard time finding studies with proper assessments of PEM. Most treat it as fatigue or use imprecise questionnaires that would also pick up DOMS, etc.
I fear there'll be few worthwhile studies, if any. I'm not sure who records how many/what proportion recover naturally. It would probably only be studied as part of a treatment trial, and as most of those involve CBT etc and don't use objective outcomes, it's difficult to make anything of them.
Thank you all so much for the ideas and links - keep them coming! The tantalizing thing is that it will just be a detail - a line or one of many figures - and I'm fairly sure I've come across at least one and thought to myself, "Yep, just like Dubbo". I'll post here if I find anything helpful.
Were you perhaps thinking of: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome After SARS-CoV-2 Infection or one of the other studies Unger was involved in? Alternatively the study might have been contained in the meta-analysis The persistence of [ME/CFS] after SARS-CoV-2 infection: A systematic review and meta-analysis, 2024, Dehlia et al (which unfortunately appears to be full of errors)?