E2 ModeratePreliminaryPEM unclearCase-ControlPeer-reviewedMachine draft
Detection of enterovirus in human skeletal muscle from patients with chronic inflammatory muscle disease or fibromyalgia and healthy subjects.
Douche-Aourik, Fatima, Berlier, Willy, Féasson, Léonard et al. · Journal of medical virology · 2003 · DOI
Quick Summary
Researchers tested muscle tissue samples from patients with fibromyalgia/ME/CFS and inflammatory muscle diseases to see if they contained enterovirus (a type of virus). They found viral genetic material in some patient samples but not in healthy people, though they did not find evidence of active viral proteins. This suggests that if a virus is present, it may be dormant or not fully active in muscle tissue.
Why It Matters
This work contributes to understanding whether persistent viral infections might underlie ME/CFS muscle pathology. Detection of viral RNA without active viral proteins could explain chronic symptoms without obvious ongoing inflammation, and supports the hypothesis that muscle tissue may harbor dormant enteroviral infections in ME/CFS patients.
Observed Findings
- Enterovirus RNA detected in 3 of 15 (20%) chronic inflammatory muscle disease patients
- Enterovirus RNA detected in 4 of 30 (13%) fibromyalgia/CFS patients
- Enterovirus RNA detected in 0 of 29 (0%) healthy control subjects
- No VP-1 enteroviral capsid protein detected in any patient or control muscle biopsies
Inferred Conclusions
- Skeletal muscle may host persistent enteroviral infection in patients with muscle disease
- The presence of viral RNA without viral capsid protein suggests defective viral replication rather than active infection
- Enterovirus persistence in muscle tissue may be a feature distinguishing patients with fibromyalgia/CFS from healthy individuals
Remaining Questions
- What is the functional significance of persistent enteroviral RNA without active viral replication in muscle?
- Does the presence of viral RNA correlate with symptom severity or disease progression in ME/CFS?
- Can defective enteroviral infection be cleared, and if so, would clearing it improve symptoms?
- Are there specific enterovirus serotypes associated with ME/CFS compared to other muscle diseases?
What This Study Does Not Prove
This study does not prove that enterovirus causes ME/CFS or fibromyalgia, only that viral RNA is more common in affected patients than controls. The absence of VP-1 protein means the virus is not actively replicating, so the clinical relevance of finding dormant viral RNA remains unclear. A small sample size and cross-sectional design prevent definitive conclusions about causation or disease mechanisms.
Tags
Symptom:PainFatigue
Biomarker:Gene Expression
Phenotype:Infection-Triggered
Method Flag:Weak Case DefinitionSmall SampleExploratory Only
Metadata
- DOI
- 10.1002/jmv.10531
- PMID
- 14556267
- Review status
- Machine draft
- Evidence level
- Single-study or moderate support from human research
- Last updated
- 8 April 2026
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 →
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