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ME/CFS Atlas — A public knowledge atlas for ME/CFS

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ME/CFS Atlas is an evidence reference platform, not a medical provider. Content is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.

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ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

Evidence browser

Search and filter 6,171 studies by evidence level, diagnostic criteria, PEM status, and research domain. Each entry links to the original source.

Studies sorted by evidence level, then year. Browse by topic instead →

Evidence level (E0–E3) reflects study type and replication, not methodological quality. A weak systematic review still sits at E0. How evidence levels work →

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1198 studies

E0 — Consensus644E1 — Replicated320E2 — Moderate2,785E3 — Preliminary2,422

ME/CFS4,028Long COVID217Post-infectious189Overlapping1,051

Required for diagnosis415Not specified / unclear2,222Not required3,534

Post-Exertional Malaise1,067Cognitive Dysfunction1,737Pain1,621Unrefreshing Sleep800Orthostatic Intolerance479

Cytokines819Gene Expression568Metabolomics475Neuroimaging468Autoantibodies458

Infection-Triggered1,175Long COVID Overlap589Pediatric494Severe231

Strong Phenotyping439Sex-Stratified327Severe ME Included118

Systematic Review266Meta-Analysis60RCT300

Peer-reviewed6,114Preprint3Unclear54

1181–1198 of 1,198 studies

E3 PreliminaryReviewPEM not requiredReview-Narrative

Nervous system-immune system communication.

Arnason, B G·Reviews of infectious diseases·1991

Some people's bodies may be genetically or biologically wired to respond to infections in a way that leads to ME/CFS. This review examines how the immune system and nervous system communicate with each other through chemical messengers like interleukin-1 and hormones. The author suggests that measuring these chemicals in patients with ME/CFS compared to healthy people could help us understand why some people develop this disease after an infection.

E3 PreliminaryReviewPEM not requiredReview-Narrative

The chronic fatigue syndrome.

Shafran, S D·The American journal of medicine·1991

ME/CFS is a serious condition causing extreme fatigue lasting at least 6 months that doctors cannot fully explain. While most patients report getting sick before their fatigue started, researchers have not found proof that any specific infection causes ME/CFS. The condition mainly affects people aged 20-50, with more women than men affected.

E3 PreliminaryReviewPEM unclearReview-Narrative

Human herpesvirus 6 (HHV6) and chronic fatigue syndrome (CFS).

Ablashi, D V, Zompetta, C, Lease, C et al.·Canada diseases weekly report = Rapport hebdomadaire des maladies au Canada·1991

This review article examines whether human herpesvirus 6 (HHV6), a common virus that infects most people in childhood, might be connected to ME/CFS. The authors gathered available evidence about HHV6 and its potential role in causing or contributing to chronic fatigue syndrome symptoms.

E3 PreliminaryCohortPEM unclearCase-Control

Fibromyalgia and parvovirus infection.

Leventhal, L J, Naides, S J, Freundlich, B·Arthritis and rheumatism·1991

This study describes three patients who developed fibromyalgia (a condition causing widespread pain and fatigue) shortly after having parvovirus B19 infections. Blood tests confirmed the virus was present, and sleep studies showed abnormal sleep patterns in two patients. The researchers suggest that doctors should look more carefully for viral infections in fibromyalgia patients whose symptoms started with flu-like illness.

E3 PreliminaryCohortPEM not requiredCase-Control

Infectious mononucleosis, Epstein-Barr virus, and chronic fatigue syndrome: a prospective case series.

Fark, A R·The Journal of family practice·1991

This study looked at whether Epstein-Barr virus (EBV), the virus that causes infectious mononucleosis (mono), might be the cause of ME/CFS. Researchers found that some people with chronic fatigue had high levels of antibodies (immune markers) against EBV, and some of them had never fully recovered from a previous mono infection. The study suggests a possible link between EBV infection and the development of chronic fatigue, though it doesn't prove the virus directly causes ME/CFS.

E3 PreliminaryMechanismPEM not requiredMechanistic

Altered cytokine release in peripheral blood mononuclear cell cultures from patients with the chronic fatigue syndrome.

Chao, C C, Janoff, E N, Hu, S X et al.·Cytokine·1991

This study found that immune cells from people with ME/CFS respond differently to stimulation than cells from healthy people. Specifically, when researchers activated these immune cells in the lab, they released higher levels of inflammatory molecules (IL-1 beta, IL-6, and TNF-alpha), suggesting that ME/CFS patients' immune cells may be in a heightened state of readiness. The study also found unusual patterns in a molecule called TGF-beta, which normally helps regulate immune responses.

E3 PreliminaryCommentaryPEM not requiredEditorial

Dual infections of the immune system in patients with chronic active Epstein-Barr virus infection mimicking chronic fatigue syndrome.

Purtilo, D T·Canada diseases weekly report = Rapport hebdomadaire des maladies au Canada·1991

This article discusses the importance of distinguishing patients with ME/CFS (the commonly recognized illness) from those who have dual infections or weakened immune systems that only look like ME/CFS. The authors argue that some patients appearing to have ME/CFS may actually have other treatable conditions involving multiple infections, and recommend long-term studies tracking people who develop ME/CFS-like symptoms after documented viral infections.

E3 PreliminaryReviewPEM not requiredReview-Narrative

[The chronic fatigue syndrome. A multifactorial approach and the treatment possibilities].

Pinardi, G, Scarlato, G·Recenti progressi in medicina·1990

This review describes ME/CFS as a complex condition marked by severe, long-lasting fatigue accompanied by symptoms like sore throat, headaches, muscle pain, and mood changes. While researchers have suspected viruses like Epstein-Barr virus might cause it, the evidence hasn't been convincing due to study design problems. The authors suggest the condition may result from an abnormal immune response rather than a single virus.

E3 PreliminaryMechanismPEM not requiredCross-Sectional

Naloxone-reversible monocyte dysfunction in patients with chronic fatigue syndrome.

Prieto, J, Subirá, M L, Castilla, A et al.·Scandinavian journal of immunology·1989

Researchers examined immune cells called monocytes in 35 ME/CFS patients and 25 healthy people. They found that most ME/CFS patients had monocytes that weren't working properly, but these cells improved dramatically when treated with naloxone, a drug that blocks opioid effects. This suggests that the body's natural opioid-like chemicals may be overactive in ME/CFS and could be damaging immune function.

E3 PreliminaryReviewPEM not requiredReview-Narrative

What's new in human herpesvirus-6? Clinical immunopathology of the HHV-6 infection.

Krueger, G R, Sander, C·Pathology, research and practice·1989

This review examines human herpesvirus-6 (HHV-6), a common virus that most people carry in a dormant state. When the immune system is weakened, this virus can reactivate and potentially cause long-lasting fatigue and other health problems. The authors discuss how HHV-6 might contribute to chronic fatigue syndrome and other conditions, particularly in people with weak immune systems.

E3 PreliminaryReviewPEM unclearReview-Narrative

The chronic fatigue syndrome: definition, current studies and lessons for fibromyalgia research.

Komaroff, A L, Goldenberg, D·The Journal of rheumatology. Supplement·1989

This review describes ME/CFS as a serious illness where extreme tiredness lasts for more than 6 months, often starting suddenly like the flu. People with ME/CFS frequently experience fever, sore throat, muscle pain, swollen lymph nodes, brain fog, and mood problems. Blood tests sometimes show changes in immune cells and antibodies, and researchers have found links between ME/CFS and several viruses, particularly Epstein-Barr virus, though no virus has been proven to directly cause the disease.

E3 PreliminaryReviewPEM not requiredReview-Narrative

Chronic fatigue syndrome: review of the literature.

Turgeon, S A·Canadian family physician Medecin de famille canadien·1989

This review article examines what was known about ME/CFS in 1989, a time when the condition was still poorly understood. The authors note that while some initially thought the Epstein-Barr virus (which causes mononucleosis) might cause ME/CFS, that theory no longer seems correct. They found evidence that both psychiatric factors and subtle immune system problems may play a role in the illness.

E3 PreliminaryMechanismPEM not requiredMechanistic

Immunotherapy and enhanced antibody-dependent cell-mediated cytotoxicity using virally-infected target cells.

Bosse, D, Ades, E W·Journal of clinical & laboratory immunology·1989

This study looked at whether adding a immune-boosting substance called IL-2 to a blood treatment (gammaglobulin) could help the body's immune cells better fight cells infected with Epstein-Barr virus. The researchers found in laboratory tests that IL-2 did enhance this immune response, and they suggested it might help ME/CFS patients who receive gammaglobulin treatment.

E3 PreliminaryCohortPEM not requiredCross-Sectional

Antibodies to Epstein-Barr virus-specific DNase and DNA polymerase in the chronic fatigue syndrome.

Jones, J F, Williams, M, Schooley, R T et al.·Archives of internal medicine·1988

This 1988 study tested whether people with ME/CFS had unusual antibody patterns against Epstein-Barr virus (EBV), a common virus that causes mononucleosis. Researchers measured antibodies against viral enzymes that are only produced when EBV is actively replicating. A small group of ME/CFS patients with very high EBV antibody levels did show these unusual enzyme antibodies, similar to patterns seen in people with nasopharyngeal cancer.

E3 PreliminaryPEM unclear

[Chronic fatigue syndrome; is there a connection with the Epstein-Barr virus?].

Berends, G M, Peeters, M F, Lepoutre, J M et al.·Nederlands tijdschrift voor geneeskunde·1988

This 1988 case study examined whether Epstein-Barr virus (EBV)—a common virus that causes infections like mononucleosis—might be connected to ME/CFS. The researchers looked at individual patient cases to explore possible links between EBV infection and the development of chronic fatigue syndrome symptoms.

E3 PreliminaryReviewPEM not requiredReview-Narrative

Human B-lymphotropic virus (human herpesvirus-6).

Ablashi, D V, Josephs, S F, Buchbinder, A et al.·Journal of virological methods·1988

This study describes a virus called human herpesvirus-6 (HHV-6) that was newly discovered in 1986. Researchers found that this virus can infect many different types of cells in the body and detected antibodies to it in about 26% of healthy people. Interestingly, they found higher levels of HHV-6 antibodies in people with certain cancers, autoimmune diseases, HIV/AIDS, and chronic fatigue syndrome, suggesting the virus may play a role in these conditions.

E3 PreliminaryReviewPEM not requiredReview-Narrative

Chronic fatigue syndromes: relationship to chronic viral infections.

Komaroff, A L·Journal of virological methods·1988

This review examines whether ME/CFS (a condition causing severe, long-lasting tiredness) is connected to chronic viral infections, particularly herpes-type viruses. The authors found that ME/CFS often starts suddenly like the flu and is associated with symptoms like fever, sore throat, and muscle pain. While blood tests sometimes show signs of viral infection, particularly Epstein-Barr virus and human herpesvirus-6, the study could not prove that these viruses actually cause ME/CFS.

E3 PreliminaryMechanismPEM not requiredCross-Sectional

Phenotypic and functional deficiency of natural killer cells in patients with chronic fatigue syndrome.

Caligiuri, M, Murray, C, Buchwald, D et al.·Journal of immunology (Baltimore, Md. : 1950)·1987

This study examined immune cells called natural killer cells in people with ME/CFS and compared them to healthy controls. Researchers found that ME/CFS patients had fewer of a specific type of natural killer cell and that these cells were less effective at fighting virus-infected cells, even after being stimulated to work harder. This suggests a potential immune system dysfunction in ME/CFS.

Or browse by topic

PEM Immune Neuro Metabolic Biomarkers Severe ME Long COVID Cognitive

Curated Collections

Thematic groupings by clinical question or research area.

Neuroinflammation Evidence

PET imaging and other studies providing evidence for brain inflammation in ME/CFS.

Metabolism & Mitochondria

Metabolomics and mitochondrial function studies revealing energy metabolism disruption.

Biomarkers

Studies identifying potential biological markers for ME/CFS diagnosis and stratification.

PEM-Specific Research

Studies specifically examining post-exertional malaise, the hallmark symptom of ME/CFS.