ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

21–40 of 46 studies

E2 ModeratePEM not requiredModerate confidenceLongitudinalEditor reviewed

Three-Month Symptom Profiles Among Symptomatic Adults With Positive and Negative Severe Acute Respiratory Syndrome Coronavirus 2 Tests: A Prospective Cohort Study From the INSPIRE Group.

Spatz, Erica S, Gottlieb, Michael, Wisk, Lauren E et al.·Clinical infectious diseases : an official publication of the Infectious Diseases Society of America·2023

This study followed adults who tested positive or negative for COVID-19 and tracked their symptoms over three months. At the three-month mark, people who had COVID-19 were much more likely to still have symptoms like fatigue, breathing problems, or muscle pain compared to those who tested negative. Importantly, symptoms of post-infectious syndromes (like unrefreshing sleep and fatigue) were common in both groups, suggesting these symptoms can occur even without COVID-19 infection.

Long COVID Overlap

E2 ModeratePEM not requiredModerate confidenceObservationalEditor reviewed

Predictors of Long COVID in Patients without Comorbidities: Data from the Polish Long-COVID Cardiovascular (PoLoCOV-CVD) Study.

Chudzik, Michał, Lewek, Joanna, Kapusta, Joanna et al.·Journal of clinical medicine·2022

This study followed 488 people without serious health conditions after they recovered from COVID-19 to see who developed Long COVID symptoms. Researchers found that people who had a severe acute COVID-19 illness, higher body weight, and joint pain during their initial infection were more likely to develop Long COVID. About 45% of those who developed Long COVID had symptoms that persisted beyond the follow-up period.

Long COVID Overlap

E2 ModeratePEM requiredModerate confidenceCross-SectionalEditor reviewed

ME/CFS and Post-Exertional Malaise among Patients with Long COVID.

Jason, Leonard A, Dorri, Joseph A·Neurology international·2022

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.

Long COVID OverlapPost-Exertional Malaise

E2 ModeratePEM unclearPreliminaryCross-SectionalEditor reviewed

Chronic fatigue syndrome: an emerging sequela in COVID-19 survivors?

Mantovani, Elisa, Mariotto, Sara, Gabbiani, Daniele et al.·Journal of neurovirology·2021

Some people who recover from COVID-19 continue to experience symptoms that look very similar to ME/CFS, including severe tiredness, pain, and difficulty thinking clearly. This study found that about 27% of COVID-19 survivors had these ME/CFS-like symptoms, and they reported worse sleep, more fatigue, and more difficulty with basic activities compared to those who recovered normally. The researchers measured markers of nerve damage and inflammation to understand what might be causing these symptoms.

Long COVID OverlapPost-Exertional Malaise

E2 ModeratePEM unclearPreliminaryObservationalEditor reviewed

Shadow Burden of Undiagnosed Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) on Society: Retrospective and Prospective-In Light of COVID-19.

Araja, Diana, Berkis, Uldis, Lunga, Asja et al.·Journal of clinical medicine·2021

This study examined how many people in Latvia may have ME/CFS symptoms but have never received a diagnosis, and investigated whether COVID-19 might cause similar long-term problems. Researchers compared symptom reports from diagnosed ME/CFS patients with undiagnosed people experiencing similar symptoms, and also tracked people who had recovered from COVID-19. The research found that undiagnosed patients face a significant financial burden on the healthcare system and themselves, and that COVID-19 can trigger ME/CFS-like symptoms in some people.

DiagnosticsLong COVID Overlap

E2 ModeratePEM unclearModerate confidenceCross-SectionalEditor reviewed

A Comprehensive Examination of Severely Ill ME/CFS Patients.

Chang, Chia-Jung, Hung, Li-Yuan, Kogelnik, Andreas M et al.·Healthcare (Basel, Switzerland)·2021

This study examined severely ill ME/CFS patients who are mostly housebound or bedbound—a group that hasn't received much research attention. Researchers found that fatigue, pain, and thinking difficulties were the most common complaints, and patients showed distinct sleep problems and hormone imbalances. The study suggests that ME/CFS and long COVID may share similar mechanisms, meaning treatments discovered for one condition could potentially help the other.

Long COVID OverlapPost-Exertional Malaise

E2 ModeratePEM not requiredPreliminaryCross-SectionalEditor reviewed

Prevalence and correlates of chronic fatigue syndrome and post-traumatic stress disorder after the outbreak of the COVID-19.

Simani, Leila, Ramezani, Mahtab, Darazam, Ilad Alavi et al.·Journal of neurovirology·2021

This study looked at whether people who survived COVID-19 developed chronic fatigue syndrome (ME/CFS) or PTSD within 6 months of infection. Among 120 COVID-19 survivors in Iran, about 2.5% met the criteria for ME/CFS and 5.8% showed signs of PTSD. Interestingly, the researchers found that having PTSD was not linked to developing ME/CFS in these patients.

Long COVID Overlap

E3 PreliminaryPEM unclearModerate confidenceEditor reviewed

The lingering shadow of epidemics: post-acute sequelae across history.

Miller, Christine M, Moen, Janna K, Iwasaki, Akiko·Trends in immunology·2026

This review examines how infections throughout history have sometimes led to lasting illnesses similar to Long COVID, including conditions like ME/CFS. The authors show that post-infection syndromes have occurred for over 100 years after various infections (flu, EBV, Lyme disease, and others), suggesting this is not a new phenomenon. They argue that modern tools and technology now give us a better opportunity to understand why some infections trigger these chronic conditions.

Long COVID Overlap

E3 PreliminaryPEM unclearPreliminaryReview-NarrativeEditor reviewed

Gulf War Illness: A Historical Review and Considerations of a Post-Viral Syndrome.

Bast, Elizabeth, Jester, Dylan J, Palacio, Ana et al.·Military medicine·2026

Gulf War Illness (GWI) is a chronic condition affecting 30-40% of veterans deployed during the 1990-1991 Gulf War, causing fatigue, pain, memory problems, digestive issues, and other symptoms similar to ME/CFS and long COVID. This review examines whether GWI might be caused by a viral infection, similar to how long COVID develops after SARS-CoV-2 infection. The authors suggest that veterans may have been exposed to a coronavirus related to MERS during their deployment, and they call for more research to explore this possibility.

Long COVID Overlap

E3 PreliminaryPEM unclearModerate confidenceReview-NarrativeEditor reviewed

Mitochondrial Dysfunction in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Syed, Abu Mohammad, Karius, Alexander K, Ma, Jin et al.·Physiology (Bethesda, Md.)·2025

This review examines how mitochondria—the parts of cells that produce energy—may not be working properly in ME/CFS patients. The authors suggest that problems with energy production in cells could explain why people with ME/CFS feel severely exhausted after physical activity. They also note that similar energy problems appear in long COVID, which suggests both conditions may share a common underlying cause.

Severe MELong COVID OverlapPost-Exertional Malaise

E3 PreliminaryPEM unclearPreliminaryEditorialEditor reviewed

Post-infective myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and post-COVID as two puzzling faces of the same medal. Recent insights.

Chirumbolo, Salvatore, Franzini, Marianno, Tirelli, Umberto·International immunopharmacology·2025

This editorial examines the similarities between ME/CFS (a long-term illness causing extreme fatigue and other symptoms) and post-COVID syndrome (long-term effects some people experience after COVID-19 infection). The authors suggest these two conditions may share common underlying biological mechanisms, even though they arise from different infections. Understanding these connections could help doctors better recognize and treat both conditions.

Long COVID Overlap

E3 PreliminaryPEM unclearModerate confidenceEditorialEditor reviewed

Long Covid in Year 5: Some Progress, Still Many Questions.

Meagher, Timothy·Journal of insurance medicine (New York, N.Y.)·2025

Five years after Long Covid was first recognized in 2020, researchers have made progress understanding the condition, but significant challenges remain. While most people's symptoms improve over time, scientists still haven't found reliable blood tests to diagnose it or effective treatments. Long Covid appears to share many similarities with ME/CFS, and the condition can develop or worsen after repeated COVID-19 infections.

Long COVID Overlap

E3 PreliminaryPEM unclearPreliminaryReview-NarrativeEditor reviewed

Considerations for Long COVID Rehabilitation in Women.

Verduzco-Gutierrez, Monica, Fleming, Talya K, Azola, Alba M·Physical medicine and rehabilitation clinics of North America·2025

Long COVID is a condition where people experience ongoing symptoms weeks or months after a COVID-19 infection. This review examines how rehabilitation can help long COVID patients, with special attention to how women are affected differently. The authors emphasize that personalized treatment plans involving multiple types of therapy and healthcare teamwork are important for recovery.

Long COVID Overlap

E3 PreliminaryPEM unclearModerate confidenceGuidelineEditor reviewed

Designing and optimizing clinical trials for long COVID.

Vogel, Julia Moore, Pollack, Beth, Spier, Ezra et al.·Life sciences·2024

This study looked at all the clinical trials being tested for Long COVID on a public database and found that most trials are not well-designed or testing treatments that have enough evidence to justify testing. The researchers recommend that future trials should test actual medications that might cure Long COVID, be able to run remotely so sick patients don't have to travel, compare Long COVID to similar illnesses like ME/CFS, include diverse patients of all backgrounds and illness levels, and involve patients as research partners.

Long COVID Overlap

E3 PreliminaryPEM unclearPreliminaryReview-NarrativeEditor reviewed

Developing a clinical-pathological framework of long COVID-related fatigue applied to public safety workers.

Lofrano-Porto, Adriana, D'Isabel, Susanne, Smith, Denise L·Frontiers in medicine·2024

This article reviews what we know about long COVID fatigue, especially in firefighters and other public safety workers. The authors explain why fatigue after COVID is so hard to diagnose and treat, since patients often look healthy on the outside even though they feel extremely tired. They describe possible biological reasons for this fatigue and discuss why it matters for workers whose jobs require them to be physically and mentally alert.

DiagnosticsLong COVID Overlap

E3 PreliminaryPEM unclearPreliminaryReview-NarrativeEditor reviewed

[Myalgic encephalomyelitis/chronic fatigue syndrome as a complication of COVID-19 post-acute syndrome in adults. Bibliographic Review].

Carrillo Uguña, Miguel Esteban, Orellana Romero, Paula Michelle·Vertex (Buenos Aires, Argentina)·2024

This review examines how some COVID-19 survivors develop symptoms very similar to ME/CFS weeks or months after their acute infection ends. The authors found that over 87% of COVID-19 patients still experience at least one symptom two months after infection, and some of these symptoms match what ME/CFS patients experience. The study suggests that COVID-19 may trigger ME/CFS-like illness in some adults, similar to how other infections have been linked to ME/CFS in the past.

Long COVID OverlapPost-Exertional Malaise

E3 PreliminaryPEM unclearPreliminaryEditorialEditor reviewed

Long COVID: a new disease?

Mirofsky, Matias, Catalano, Hugo·Medicina·2024

This article discusses whether Long COVID should be considered a new disease and examines how medical systems can avoid overtreatment. The authors note that Long COVID shares similarities with other post-infection illnesses like ME/CFS and fibromyalgia, and they argue that careful, thoughtful medical care is important to prevent unnecessary treatments from making patients worse.

Long COVID Overlap

E3 PreliminaryPEM unclearModerate confidenceReview-NarrativeEditor reviewed

Long COVID: major findings, mechanisms and recommendations.

Davis, Hannah E, McCorkell, Lisa, Vogel, Julia Moore et al.·Nature reviews. Microbiology·2023

Long COVID is a serious illness affecting at least 10% of people who had COVID-19, with an estimated 65 million people worldwide experiencing it. The condition causes over 200 different symptoms affecting many body systems, similar to ME/CFS and other post-viral illnesses. This review examines what scientists have learned about Long COVID's causes and effects, though better diagnostic tests and treatments are still urgently needed.

Long COVID OverlapPost-Exertional Malaise

E3 PreliminaryPEM unclearPreliminaryReview-NarrativeEditor reviewed

Unexplained post-acute infection syndromes.

Choutka, Jan, Jansari, Viraj, Hornig, Mady et al.·Nature medicine·2022

This review explains that several different infections—not just COVID-19—can sometimes cause long-lasting illness in some people who recover from the initial infection. These post-infection conditions share similar symptoms and overlap with ME/CFS, suggesting they might have common underlying causes that scientists don't yet understand. The authors argue that researchers need to invest more effort in understanding why and how these mysterious long-term illnesses develop.

Long COVID Overlap

E3 PreliminaryPEM unclearPreliminaryReview-NarrativeEditor reviewed

COVID-19 and chronic fatigue syndrome: An endocrine perspective.

Bansal, Rashika, Gubbi, Sriram, Koch, Christian A·Journal of clinical & translational endocrinology·2022

Some people who recover from COVID-19 experience long-lasting exhaustion and other debilitating symptoms similar to ME/CFS. This review examines how COVID-19 might affect the body's hormone systems, particularly the glands that control stress response and energy levels. The authors suggest doctors should check patients' hormone levels as part of their care plan.

Endocrine DisruptionLong COVID Overlap

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Three-Month Symptom Profiles Among Symptomatic Adults With Positive and Negative Severe Acute Respiratory Syndrome Coronavirus 2 Tests: A Prospective Cohort Study From the INSPIRE Group.

Predictors of Long COVID in Patients without Comorbidities: Data from the Polish Long-COVID Cardiovascular (PoLoCOV-CVD) Study.

ME/CFS and Post-Exertional Malaise among Patients with Long COVID.

Chronic fatigue syndrome: an emerging sequela in COVID-19 survivors?

Shadow Burden of Undiagnosed Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) on Society: Retrospective and Prospective-In Light of COVID-19.

A Comprehensive Examination of Severely Ill ME/CFS Patients.

Prevalence and correlates of chronic fatigue syndrome and post-traumatic stress disorder after the outbreak of the COVID-19.

The lingering shadow of epidemics: post-acute sequelae across history.

Gulf War Illness: A Historical Review and Considerations of a Post-Viral Syndrome.

Mitochondrial Dysfunction in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Post-infective myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and post-COVID as two puzzling faces of the same medal. Recent insights.

Long Covid in Year 5: Some Progress, Still Many Questions.

Considerations for Long COVID Rehabilitation in Women.

Designing and optimizing clinical trials for long COVID.

Developing a clinical-pathological framework of long COVID-related fatigue applied to public safety workers.

[Myalgic encephalomyelitis/chronic fatigue syndrome as a complication of COVID-19 post-acute syndrome in adults. Bibliographic Review].

Long COVID: a new disease?

Long COVID: major findings, mechanisms and recommendations.

Unexplained post-acute infection syndromes.

COVID-19 and chronic fatigue syndrome: An endocrine perspective.

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