Jason, Leonard A, Dorri, Joseph A · Neurology international · 2022 · DOI
Researchers studied 465 people with long-term COVID symptoms to see how many also had ME/CFS (a serious condition causing extreme fatigue and worsening after activity). They found that about 6 in 10 people with long COVID met the medical criteria for ME/CFS. Interestingly, some people thought they had ME/CFS when they didn't, while others had ME/CFS without realizing it—showing that self-diagnosis alone isn't reliable.
This study quantifies the substantial overlap between Long COVID and ME/CFS, challenging the assumption that Long COVID and ME/CFS are entirely separate conditions. It demonstrates that objective diagnostic criteria are essential because patient self-report alone misses or over-identifies ME/CFS, which has implications for clinical recognition, patient support, and research stratification.
This study does not prove that Long COVID causes ME/CFS or establish the mechanistic relationship between them—it only documents their co-occurrence at one time point. The cross-sectional design cannot determine whether ME/CFS develops during Long COVID or represents a pre-existing condition, nor does it clarify whether they share identical biological pathways.
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →
The first block is for the primary paper and is the citation you should use in research work. The atlas-snapshot line only applies if you are specifically referring to this atlas’s reading of the paper on the date shown.
Primary citation
Jason, Leonard A & Dorri, Joseph A (2022). ME/CFS and Post-Exertional Malaise among Patients with Long COVID.. Neurology international. https://doi.org/10.3390/neurolint15010001
BibTeX
@article{mecfsatlas-jason-2022-cfs-post,
author = {Jason, Leonard A and Dorri, Joseph A},
title = {ME/CFS and Post-Exertional Malaise among Patients with Long COVID.},
journal = {Neurology international},
year = {2022},
doi = {10.3390/neurolint15010001},
note = {PubMed: 36648965},
url = {https://www.mecfsatlas.com/evidence/jason-2022-cfs-post},
}Atlas snapshot reference
ME/CFS Atlas. Generator v1 / Scanner v1.4 / policy v0.1. Accessed 2026-05-26. https://www.mecfsatlas.com/evidence/jason-2022-cfs-post
Contribute
Private, reviewed by a human. Not a public comment thread.