Exploratory study on autoantibodies to arginine-rich human peptides mimicking Epstein-Barr virus in women with post-COVID and myalgic encephalomyelitis/chronic fatigue syndrom

Abstract:

Introduction: Epstein-Barr virus (EBV) infection is a well-established trigger and risk factor for both myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and post-COVID syndrome (PCS). In previous studies, we identified elevated IgG responses to arginine-rich (poly-R) sequences within the EBV nuclear antigens EBNA4 and EBNA6 in post-infectious ME/CFS (piME/CFS). Building on these findings, this exploratory study examines IgG reactivity to poly-R-containing EBV-derived peptides and homologous human peptides in women with PCS and ME/CFS.

Methods: IgG reactivity to poly-R containing peptides derived from EBNA4 and EBNA6, and homologous human 15-mer peptides and the corresponding full-length proteins, was assessed using a cytometric bead array (CBA) and a multiplex dot-blot assay. Serum samples were analyzed from 45 female PCS patients diagnosed according to WHO criteria, including 26 who also met the Canadian Consensus criteria for ME/CFS (pcME/CFS), 36 female patients with non-COVID post-infectious ME/CFS (piME/CFS), and 34 female healthy controls (HC).

Results: Autoantibodies targeting poly-R peptide sequences of the neuronal antigen SRRM3, the ion channel SLC24A3, TGF-β signaling regulator TSPLY2, and the angiogenesis-related protein TSPYL5, as well as full-length α-adrenergic receptor (ADRA) proteins, were more frequently detected in patient groups. Several of these autoantibodies showed positive correlations with core symptoms, including autonomic dysfunction, fatigue, cognitive impairment, and pain.

Conclusion: This exploratory study identify autoantibodies directed against EBV mimicking arginine-rich sequences in human proteins, suggesting a potential role for molecular mimicry in the pathogenesis of PCS and ME/CFS.

Source: Hoheisel Friederike , Fleischer Kathrin Maria , Rubarth Kerstin , Sepúlveda Nuno , Bauer Sandra , Konietschke Frank , Kedor Peters Claudia , Stein Annika Elisa , Wittke Kirsten , Seifert Martina , Bellmann-Strobl Judith , Mautner Josef , Behrends Uta , Scheibenbogen Carmen , Sotzny Franziska. Exploratory study on autoantibodies to arginine-rich human peptides mimicking Epstein-Barr virus in women with post-COVID and myalgic encephalomyelitis/chronic fatigue syndrome. Frontiers in Immunology, Volume 16 – 2025. DOI=10.3389/fimmu.2025.1650948 ISSN=1664-3224 https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2025.1650948/full (Full text)

Impacts of long COVID on disability, function and quality of life for adults living in Australia

Abstract:

Background: To describe the impact of long COVID on disability, function and quality of life among adults living in Australia.

Method: People aged >18years with a history of COVID-19 infection confirmed by polymerase chain reaction or rapid antigen test were eligible for this cross-sectional survey. The World Health Organization Disability Assessment Schedule 2.0 measured disability and function, and the 36-Item Short Form Health Survey assessed quality of life.

Results: Participants (n =121) reported significant functional impairment and reduced quality of life compared with established population norms for these outcome measures. Most (n =104, 86%) reported clinically significant disability and participation limitations in daily activities. Mean World Health Organization Disability Assessment Schedule 2.0 scores indicated higher levels of disability than 98% of the general population. The 36-Item Short Form Health Survey scores indicated lower quality of life across all domains, but particularly in relation to vitality and social functioning. Regression analysis found significant associations between the World Health Organization Disability Assessment Schedule 2.0 and 36-Item Short Form Health Survey scores, and vaccine dose number, comorbidities and self-rated recovery.

Conclusion: Long COVID is associated with significantly reduced function and quality of life, which are distinct outcomes requiring targeted assessment and intervention. The overall impact may be exacerbated in people with pre-existing comorbidities who are more susceptible to long COVID in the first place. The findings underscore the need for targeted rehabilitation and support services for people living in Australia with long COVID, and further longitudinal research to explore the long-term impact on disability and quality of life, and inform policy and healthcare service delivery.

Source: Hitch D, Botha T, Tesfay F, Holton S, Said CM, Hensher M, Richards K, Angeles MR, Bennett CM, Pepin G, Rasmussen B, Nicola-Richmond K. Impacts of long COVID on disability, function and quality of life for adults living in Australia. Aust J Prim Health. 2025 Aug;31:PY25033. doi: 10.1071/PY25033. PMID: 40977216. https://www.publish.csiro.au/py/Fulltext/PY25033 (Full text)

Telehealth as a care solution for homebound people: systematic review and meta-analysis of healthcare utilization, quality of life, and well-being outcomes

Abstract:

Homebound individuals residing in community settings with severe health conditions and disabilities could arguably benefit from telehealth interventions. However, the effectiveness of telehealth compared to in-person care remains underexplored, considering the diversity of these groups. This systematic review and meta-analysis aimed to evaluate the effectiveness of telehealth in reducing healthcare utilization and improving health-related quality of life (HRQOL) and well-being in homebound populations.

Adhering and expanding on a published protocol, we conducted comprehensive search across multiple databases: MEDLINE, Embase, PsycINFO, CINAHL, Cochrane Central Register of Controlled Trials (CENTRAL), Scopus, LILACS, and the Web of Science, with no restrictions on language or publication date, and experimental and quasiexperimental studies considered. Eleven independent reviewers were responsible for study selection, and three for data extraction. The methodological quality of the included studies was assessed using JBI checklists. A meta-analysis was then performed using Stata software, which reported standardized mean differences (SMDs) as the effect measure, with the quality of evidence evaluated using the GRADE approach. From an initial screening of 3289 articles, ten studies met our inclusion criteria, with eight suitable for meta-analysis. These studies encompassed data from 2245 participants.

Our findings revealed that telehealth interventions significantly reduced healthcare utilization (SMD: −0.49; 95% CI: −0.76 to −0.22; p < 0.01, GRADE: low certainty), significantly enhanced HRQOL (SMD: 0.18; 95% CI: 0.01 to 0.35; p = 0.04, GRADE: moderate certainty), and significantly improved well-being (SMD: −0.31; 95% CI: −0.47 to −0.15; p < 0.01, GRADE: moderate certainty) compared to in-person care. Thus, telehealth emerges as a viable alternative to conventional care, significantly reducing healthcare utilization and enhancing both HRQOL and well-being for homebound people.

These findings underscore the potential of telehealth to mitigate healthcare disparities and emphasize the need for accessible, equitable telehealth services codeveloped with end users and relevant stakeholders to save resources and maximize health outcomes for vulnerable populations in community settings.

Source: Pinero de Plaza, Maria Alejandra, Gulyani, Aarti, Bulto, Lemma N., Allande-Cussó, Regina, Pearson, Vincent, Lange, Belinda, Marin, Tania, Gebremichael, Lemlem, Brown, Shannon, Dafny, Hila, Sajeev, Shelda, Bulamu, Norma, Beleigoli, Alline, Nesbitt, Katie, McMillan, Penelope, Clark, Robyn, Tieu, Matthew, Kitson, Alison, Champion, Stephanie, Hines, Sonia, Hendriks, Jeroen M., Telehealth as a Care Solution for Homebound People: Systematic Review and Meta-Analysis of Healthcare Utilization, Quality of Life, and Well-Being Outcomes, Health & Social Care in the Community, 2025, 7224151, 32 pages, 2025. https://doi.org/10.1155/hsc/7224151 https://onlinelibrary.wiley.com/doi/full/10.1155/hsc/7224151 (Full text)

Systemic increase of AMPA receptors associated with cognitive impairment of Long COVID

Abstract:

Long COVID primarily presents with persistent cognitive impairment (Cog-LC), imposing a substantial and lasting global burden. Even after the pandemic, there remains a critical global need for diagnostic and therapeutic strategies targeting Cog-LC. Nevertheless, the underlying neural mechanisms remain poorly understood. Given the central role of synapses in brain function, investigation of synaptic molecular changes may provide vital insights into Cog-LC pathophysiology.

In this study, we used [11C]K-2 PET to characterize the density of AMPA receptors (AMPARs) on the post-synaptic cell surface, which are crucial synaptic components in brain signalling. Statistical parametrical mapping was used to spatially normalize and apply independent t-test for a voxel-based comparison.

We selected patients with Cog-LC (n = 30) based on Repeatable Battery for the Assessment of Neuropsychological Status assessed persistent cognitive impairment and healthy controls (n = 80) with no diagnosed neuropsychiatric disorders. The primary objective was to compare [11C]K-2 standardized uptake value ratio with white matter (SUVRWM) as a reference region between patients with Cog-LC and healthy controls, and to define the regional extent of differences. The secondary objective was to examine associations between [11C]K-2 SUVRWM and plasma concentrations of cytokines or chemokines.

As an exploratory objective, we tested whether [11C]K-2 PET data could distinguish Cog-LC from healthy controls using a partial least squares based classification algorithm. A voxel-based comparison (P < 0.05, T > 1.66, one-tailed, false discovery rate control) and a volume of interests analysis (P < 0.05, Bonferroni multiple comparison) demonstrated that increased index of AMPAR density in large parts of the brains of patients with Cog-LC compared with that in healthy controls.

A voxel-based correlation analysis also showed the brain regions where [11C]K-2 SUVRWM correlated positively with plasma TNFSF12 and negatively with plasma CCL2 concentrations.

A partial least squares model trained on the index of AMPAR density data demonstrated high diagnostic accuracy, achieving 100% sensitivity and 91.2% specificity. [11C]K-2 PET signal represents the index of AMPAR density on the post-synaptic neural cell surface, not on the glial cell surface.

A systemic increase in synaptic AMPARs across the brain may drive abnormal information processing in Cog-LC and, through excessive excitatory signalling, pose a risk of excitotoxic neuronal damage.

We derived the hypothesis that [11C]K-2 PET would be helpful in establishing a diagnostic framework for Cog-LC and that antagonists for cell surface AMPARs, such as perampanel, would be a potential therapeutic target. These hypotheses should be investigated in future large-scale clinical studies.

Source: Fujimoto Y, Abe H, Eiro T, Tsugawa S, Tanaka M, Hatano M, Nakajima W, Ichijo S, Arisawa T, Takada Y, Kimura K, Sano A, Hirahata K, Sasaki N, Kimura Y, Takahashi T. Systemic increase of AMPA receptors associated with cognitive impairment of long COVID. Brain Commun. 2025 Oct 1;7(5):fcaf337. doi: 10.1093/braincomms/fcaf337. PMID: 41036177; PMCID: PMC12483584. https://pmc.ncbi.nlm.nih.gov/articles/PMC12483584/ (Full text)

Reinfection with SARS-CoV-2 in the Omicron Era is Associated with Increased Risk of Post-Acute Sequelae of SARS-CoV-2 Infection: A RECOVER-EHR Cohort Study

Abstract:

Importance: Post-acute sequelae of SARS-CoV-2 infection (PASC) remains a major public health challenge. While previous studies have focused on characterizing PASC and identifying its subphenotypes in children and adolescents following an initial SARS-CoV-2 infection, the risks of PASC with Omicron-variant reinfections remain unclear. Using a real-world data approach, this study investigates the risks of PASC following reinfections during the Omicron phase in the pediatric population.

Objective: To investigate the risks of PASC diagnosis and 24 PASC symptoms and conditions after reinfection of SARS-CoV-2 during Omicron period in the pediatric population.

Design setting and participants: This retrospective cohort study used data from the RECOVER consortium comprising 40 children’s hospitals and health institutions in U.S. between January 2022 and October 2023.

Exposures: A second SARS-CoV-2 infection, confirmed by a positive polymerase-chain-reaction (PCR) or antigen tests, or a diagnose of COVID-19, occurring at least 60 days after the initial infection, compared to the initial infection.

Main outcomes and measures: PASC was identified using two approaches: (1) the ICD-10-CM diagnosis code U09.9 and (2) a symptom-based definition including 24 physician-identified symptoms and conditions. Absolute risks of incident PASC were reported, and relative risks (RRs) were calculated by comparing the second infection episode with the first infection episode groups using a modified Poisson regression model, adjusting for demographic, clinical, and healthcare utilization factors through exact matching and propensity scoring matching.

Results: A total of 465,717 individuals under 21 years old (mean [SD] age 8.17 [6.58] years; 52% male) were included. Compared to the first infection, a second infection was associated with significantly increased risk of an overall PASC diagnosis (RR, 2.08; 95% confidence interval [CI], 1.68-2.59), and with many specific conditions including: myocarditis (RR, 3.60; 95% CI, 1.46-8.86); changes in taste and smell (RR, 2.83; 95% CI, 1.41-5.67); thrombophlebitis and thromboembolism (RR, 2.28; 95% CI, 1.71-3.04); heart disease (RR, 1.96; 95% CI, 1.69 to 2.28); acute kidney injury (RR, 1.90; 95% CI, 1.38 to 2.61); fluid and electrolyte (RR, 1.89; 95% CI, 1.62 to 2.20); generalized pain (RR, 1.70; 95% CI, 1.48 to ; arrhythmias (RR, 1.59; 95% CI, 1.45-1.74); abnormal liver enzyme (RR, 1.56; 95% CI, 1.24 to ; fatigue and malaise (RR, 1.50; 95% CI, 1.38 to 1.64); musculoskeletal pain (RR, 1.45; 95% CI, 1.37 to 1.54); abdominal pain (RR, 1.42; 95% CI, 1.34 to 1.50); postural orthostatic tachycardia syndromes (POTS)/dysautonomia (RR, 1.35; 95% CI, 1.20 to 1.51); cognitive functions (RR, 1.32; 95% CI, 1.15 to 1.50); and respiratory signs and symptoms (RR, 1.29; 95% CI, 1.25 to 1.33). The risks were consistent across various organ systems, including cardiovascular, respiratory, gastrointestinal, neurological, and musculoskeletal systems.

Conclusions and relevance: Children and adolescents face significantly higher risk of various PASC outcomes after reinfection with SARS-CoV-2. These findings suggest a cumulative risk of PASC and highlight the urgent need for targeted prevention strategies to reduce reinfections, which includes an increased emphasis on initial or re-vaccination of children.

Source: Zhang B, Wu Q, Jhaveri R, Zhou T, Becich MJ, Bisyuk Y, Blanceró F, Chrischilles EA, Chuang CH, Cowell LG, Fort D, Horowitz CR, Kim S, Ladino N, Liebovitz DM, Liu M, Mosa ASM, Schwenk HT, Suresh S, Taylor BW, Williams DA, Morris JS, Forrest CB, Chen Y. Reinfection with SARS-CoV-2 in the Omicron Era is Associated with Increased Risk of Post-Acute Sequelae of SARS-CoV-2 Infection: A RECOVER-EHR Cohort Study. medRxiv [Preprint]. 2025 Mar 30:2025.03.28.25324858. doi: 10.1101/2025.03.28.25324858. PMID: 40196285; PMCID: PMC11974971. https://pmc.ncbi.nlm.nih.gov/articles/PMC11974971/ (Full text)

Long COVID associated with SARS-CoV-2 reinfection among children and adolescents in the omicron era (RECOVER-EHR): a retrospective cohort study

Summary:

Background: Post-acute sequelae of SARS-CoV-2 infection (PASC) remain a major public health challenge. Although previous studies have focused on characterising PASC in children and adolescents after an initial infection, the risks of PASC after reinfection with the omicron variant remain unclear. We aimed to assess the risk of PASC diagnosis (U09.9) and symptoms and conditions potentially related to PASC in children and adolescents after a SARS-CoV-2 reinfection during the omicron period.

Methods: This retrospective cohort study used data from 40 children’s hospitals and health institutions in the USA participating in the Researching COVID to Enhance Recovery (RECOVER) Initiative. We included patients younger than 21 years at the time of cohort entry; with documented SARS-CoV-2 infection after Jan 1, 2022; and who had at least one health-care visit within 24 months to 7 days before the first infection. The second SARS-CoV-2 infection was confirmed by positive PCR, antigen tests, or a diagnosis of COVID-19 that occurred at least 60 days after the first infection. The primary endpoint was a clinician-documented diagnosis of PASC (U09.9). Secondary endpoints were 24 symptoms and conditions previously identified as being potentially related to PASC. We used the modified Poisson regression model to estimate the relative risk (RR) between the second and first infection episodes, adjusted for demographic, clinical, and health-care utilisation factors using exact and propensity-score matching.

Findings: We identified 407 300 (87·5%) of 465 717 eligible children and adolescents with a first infection episode and 58 417 (12·5%) with a second infection episode from Jan 1, 2022, to Oct 13, 2023, in the RECOVER database. 233 842 (50·2%) patients were male and 231 875 (49·8%) were female. The mean age was 8·17 years (SD 6·58). The incident rate of PASC diagnosis (U09.9) per million people per 6 months was 903·7 (95% CI 780·9–1026·5) in the first infection group and 1883·7 (1565·1–2202·3) in the second infection group. Reinfection was associated with a significantly increased risk of an overall PASC diagnosis (U09.9) (RR 2·08 [1·68–2·59]) and a range of symptoms and conditions potentially related to PASC (RR range 1·15–3·60), including myocarditis, changes in taste and smell, thrombophlebitis and thromboembolism, heart disease, acute kidney injury, fluid and electrolyte disturbance, generalised pain, arrhythmias, abnormal liver enzymes, chest pain, fatigue and malaise, headache, musculoskeletal pain, abdominal pain, mental ill health, POTS or dysautonomia, cognitive impairment, skin conditions, fever and chills, respiratory signs and symptoms, and cardiovascular signs and symptoms.

Interpretation: Children and adolescents face a significantly higher risk of various PASC outcomes after reinfection with SARS-CoV-2. These findings add to previous evidence linking paediatric long COVID to multisystem effects and highlight the need to promote vaccination in younger populations and support ongoing research to better understand PASC, identify high-risk subgroups, and improve prevention and care strategies.

Funding: National Institutes of Health.

Source: Zhang, Bingyu et al. Long COVID associated with SARS-CoV-2 reinfection among children and adolescents in the omicron era (RECOVER-EHR): a retrospective cohort study. The Lancet Infectious Diseases, Volume 0, Issue 0, Online first; September 30, 2025. https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(25)00476-1/fulltext (Full text)

Specialised care for severely affected ME/CFS patients

Abstract:

Introduction: A specialised care unit for severely and very severely ill ME/CFS patients opened in 2021. The results from the first 3 years are reported.

Methods: People with ME/CFS who were diagnosed according to the Canadian Consensus Criteria, who are aged 18 or above with severe or very severe ME/CFS according to the UK NICE guidelines, are eligible to stay at Røysumtunet. The study design is a retrospective review of medical records.

Results: Between June 2021 and June 2024, 24 ME/CFS patients, 20 women and 4 men with a confirmed diagnosis of ME, were admitted to the unit for stays of at least 3 months. Seventeen were very severely affected and 7 were severely affected. Ages ranged from 18 to 68 years, with mean (SD) 37.5 (12.8) years. Seven patients showed significant improvement (p < 0.01), and five others showed some improvement. In total 50% improved (p < 0.01). Patients who improved were borderline significantly younger than those who did not, with a mean age of 30.3 (SD 12.6) years compared to 39.8 (SD 11.8) years (p = 0.06). The mean duration of disease was 2.3 (1.3) years for those who improved versus 6.7 (3.9) years for those who did not improve (p < 0.05).

Conclusion: This is the first report of a specialised care unit for the most severely ill ME/CFS patients. Fifty per cent of patients showed significant or partial improvement. The mechanisms behind these improvements are discussed but require further exploration in future studies.

Source: Saugstad, O. D., Sollie, M. G., Torp, H. A., & Storla, D. G. (2025). Specialised care for severely affected ME/CFS patients. Fatigue: Biomedicine, Health &amp; Behavior, 1–13. https://doi.org/10.1080/21641846.2025.2565101 https://www.tandfonline.com/doi/full/10.1080/21641846.2025.2565101 (Full text)

Understanding Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Physical Fatigue Through the Perspective of Immunosenescence

Abstract:

Background: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating illness marked by persistent fatigue, yet its mechanisms remain unclear. Growing evidence implicates immunosenescence-the age-related decline in immune function-in the onset and persistence of fatigue.

Methods: This review synthesizes clinical and experimental data to examine how immunosenescence contributes to ME/CFS. We focus on chronic inflammation, senescent immune phenotypes, mitochondrial dysfunction, and neuroendocrine imbalance, with emphasis on maladaptive crosstalk among immune, muscular, neuroendocrine, and vascular systems.

Results: Aging immune cells drive chronic inflammation that impairs mitochondrial ATP production and promotes muscle catabolism. Concurrently, HPA-axis suppression and β2-adrenergic dysfunction amplify immune dysregulation and energy imbalance. Together, these processes illustrate how immunosenescence sustains pathological cross-organ signaling underlying systemic fatigue.

Conclusion: Immunosenescence provides a unifying framework linking immune, metabolic, and neuroendocrine dysfunction in ME/CFS. Recognizing cross-organ communication highlights its clinical relevance, suggesting biomarkers such as cytokines and exhaustion markers, and supports integrated therapeutic strategies targeting immune and metabolic networks.

Source: Luo Y, Xu H, Xiong S, Ke J. Understanding Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Physical Fatigue Through the Perspective of Immunosenescence. Compr Physiol. 2025 Oct;15(5):e70056. doi: 10.1002/cph4.70056. PMID: 41017304. https://pubmed.ncbi.nlm.nih.gov/41017304/

The gut microbial composition is different in chronic fatigue syndrome than in healthy controls

Abstract:

The pathogenesis of Chronic Fatigue Syndrome (CFS) is yet unknown. This study aimed to assess the gut microbial composition in CFS patients versus in healthy controls (HCs).

The composition of fecal bacteria was examined in twenty-five CFS patients and sixteen HCs using Illumina sequencing of 16 S rRNA gene amplicons targeting the V3-V4 bacterial gene regions. 143 (46%) of the microbial genera were found only in the CFS. In addition, the gut microbial composition in the CFS patients contained a much higher proportion of the 10 most commonly found bacteria compared to the HCs group. A significantly lower observed number of operational taxonomic units (OTUs) was noted in CFS compared to HCs (p = 0.045).

Significant between-group differences in the gut microbial composition in CFS compared to HCs were noted. The three most discriminating Amplicon Sequencing Variants (ASVs): ASV 191, ASV 44, and ASV 75, were identified as significantly more abundant in the healthy control group compared to the patient group. In addition, the Neural Network (multilayer perceptron) was able to discriminate gut microbial composition from CFS versus HCs with excellent performance (AUC = 0.935).

The gut microbial composition is different in CFS patients compared to HCs. Further studies should assess the pathophysiological consequences of these differences as well as the effectiveness of therapies aimed at modifying the gut microbial composition in CFS patients.

Source: Prylińska-Jaśkowiak M, Tabisz H, Kujawski S, Godlewska BR, Słomko J, Januszko-Giergielewicz B, Murovska M, Morten KJ, Sokołowski Ł, Zalewski P. The gut microbial composition is different in chronic fatigue syndrome than in healthy controls. Sci Rep. 2025 Sep 26;15(1):33075. doi: 10.1038/s41598-025-16438-y. PMID: 41006438. https://www.nature.com/articles/s41598-025-16438-y (Full text)