Long COVID: a clinical update

SARS-CoV-2 epidemiology, kinetics, and evolution: A narrative review

Since winter 2019, SARS-CoV-2 has emerged, spread, and evolved all around the globe. We explore 4 y of evolutionary epidemiology of this virus, ranging from the applied public health challenges to the more conceptual evolutionary biology perspectives. Through this review, we first present the spread and lethality of the infections it causes, starting from its emergence in Wuhan (China) from the initial epidemics all around the world, compare the virus to other betacoronaviruses, focus on its airborne transmission, compare containment strategies ("zero-COVID" vs. "herd immunity"), explain its phylogeographical tracking, underline the importance of natural selection on the epidemics, mention its within-host population dynamics. Finally, we discuss how the pandemic has transformed (or should transform) the surveillance and prevention of viral respiratory infections and identify perspectives for the research on epidemiology of COVID-19.

Myelin dysfunction in aging and brain disorders: mechanisms and therapeutic opportunities

Myelin is a multilamellar membrane that surrounds axons in the vertebrate nervous system. Properly functioning myelin is essential for the rapid conduction of nerve impulses, and it metabolically supports axonal integrity. Emerging evidence indicates that myelin is also involved in various aspects of cognition, with adaptive myelination playing a critical role in memory consolidation and motor learning. However, these physiological processes can be disrupted in various diseases. Understanding the mechanisms underlying myelin pathology is therefore essential for the development of targeted therapies for associated medical conditions. This review provides a comprehensive overview of the role of myelin in neural function, with a particular focus on adaptive myelination in cognition. We also highlight myelin dysfunction and the underlying mechanisms in the aging brain, as well as in diverse brain disorders and neurological conditions, including neurodegenerative diseases, psychiatric conditions, brain injuries, chemotherapy-related cognitive impairment, and neurological symptoms associated with COVID-19. Furthermore, we discuss the therapeutic potential of recently identified pro-myelinating compounds in aging-associated cognitive decline and brain disorders, as well as the future of remyelination therapies. Current evidence suggests that restoring functional myelin may serve as a therapeutic strategy for various medical conditions associated with myelin dysfunction.

Submaximal 2-day cardiopulmonary exercise testing to assess exercise capacity and post-exertional symptom exacerbation in people with long COVID

Long COVID has a complex pathology and a heterogeneous symptom profile that impacts quality of life and functional status. Post-exertional symptom exacerbation (PESE) affects one-third of people living with long COVID, but the physiological basis of impaired physical function remains poorly understood. Sixty-eight people (age (mean ± SD): 50 ± 11 years, 46 females (68%)) were screened for severity of PESE and completed two submaximal cardiopulmonary exercise tests separated by 24 h. Work rate was stratified relative to functional status and was set at 10, 20 or 30 W, increasing by 5 W/min for a maximum of 12 min. At the first ventilatory threshold (VT1),V ̇ O 2 ${\dot V_{{{\mathrm{O}}_2}}}$ was 0.73 ± 0.16 L/min on Day 1 and decreased on Day 2 (0.68 ± 0.16 L/min; P = 0.003). Work rate at VT1 was lower on Day 2 (Day 1 vs. Day 2; 28 ± 13 vs. 24 ± 12 W; P = 0.004). Oxygen pulse on Day 1 at VT1 was 8.2 ± 2.2 mL/beat and was reduced on Day 2 (7.5 ± 1.8 mL/beat; P = 0.002). The partial pressure of end tidal carbon dioxide was reduced on Day 2 (Day 1 vs. Day 2; 38 ± 3.8 vs. 37 ± 3.2 mmHg; P = 0.010). ImpairedV ̇ O 2 ${\dot V_{{{\mathrm{O}}_2}}}$ is indicative of reduced transport and/or utilisation of oxygen.V ̇ O 2 ${\dot V_{{{\mathrm{O}}_2}}}$ at VT1 was impaired on Day 2, highlighting worsened function in the 24 h after submaximal exercise. The data suggest multiple contributing physiological mechanisms across different systems and further research is needed to investigate these areas.

The association between perceived COVID-19-related discrimination and probable depression among pregnant women in the post-pandemic era: a cross-sectional study

The 2019 coronavirus disease (COVID-19) has substantially influenced the physical and psychological wellbeing of populations who survived the pandemic. Discrimination against infected individuals has been a public health concern and has been identified as a risk factor for mental health issues. However, limited empirical evidence is available to support its role in psychological disorders during the prenatal period. The current study aims to investigate the association between COVID-19-related discrimination and the likelihood of experiencing probable depression among women in their early pregnancy. A cross-sectional study was conducted from 1 May 2023 to 31 August 2023 using an anonymous online questionnaire distributed to women in their first trimester of pregnancy in the antenatal care clinic of three hospitals. The Edinburgh Postnatal Depression Scale was used to screen antenatal depression. The logistic regression model was used to assess the relationship between COVID-19-related discrimination and antenatal depression. A total of 3,608 pregnant women were enrolled in this study, of whom 657 screened positive for antenatal depression (AND), resulting in a prevalence of 18.2%. More than one-third of the participants experienced COVID-19-related discrimination. The logistic regression analysis demonstrated a greater prevalence of probable depression among pregnant women who experienced COVID-19-related discrimination compared with those who did not. This study provided novel evidence for the association between COVID-19-related discrimination and probable depression in pregnant women, highlighting an associated factor for supportive interventions that may be relevant in the post-pandemic era.

Respiratory post COVID sequelae: the role of pulmonary function impairment, fatigue and obesity in dyspnea and the impact of SPA rehabilitation

BACKGROUND

Respiratory COVID-19 post-acute sequelae (PASC) may persist for extended periods following recovery.

METHODS

Patients with PASC who were referred for Salus Per Aquam (SPA) therapy were enrolled in the study.

AIM

To categorize patients based on the presence of dyspnea and fatigue, with a specific focus on obesity, chronic respiratory conditions, and predictors of rehabilitation outcomes.

RESULTS

From July-November 2021, 327 consecutive patients were enrolled at the spa center. Among these, 31% had been previously hospitalized, 5% had required noninvasive or invasive mechanical ventilation. Approximately one-third of the cohort underwent DLCO testing, which was abnormal in 56.3% of cases. Patients with impaired DLCO had significantly higher dyspnea rates compared to those with normal DLCO (88.9% vs. 64.3%, p < 0.0001). Dyspneic patients were more likely to have one or more comorbidities (p < 0.001), be obese (p = 0.005), and have a history of chronic respiratory disease (p = 0.0009). Patients reporting fatigue also had higher rates of dyspnea (91.2% vs. 61.5%, p < 0.0001), were more frequently obese (p = 0.03), had more comorbidities (p = 0.02), and had a greater history of hospitalization (p = 0.02). No improvement in dyspnea/fatigue was observed post-SPA treatment among patients with DLCO impairment and obese. However, patients with chronic respiratory conditions reported benefit.

CONCLUSIONS

Dyspnea in PASC is complex and multifactorial. The findings suggest that SPA rehabilitation may be particularly beneficial for alleviating fatigue and enhancing overall well-being in selected subgroups of patients with PASC.

Post-COVID-19 condition: clinical phenotypes, pathophysiological mechanisms, pathology, and management strategies

Post-COVID-19 condition (PCC), also known as long COVID, is a complex multiple organ system condition that can develop and persist for months after acute COVID-19. PCC encompasses a wide range of symptoms, resulting in heterogeneous clinical manifestations. These manifestations likely arise from diverse underlying pathophysiological mechanisms, which, in turn, are influenced by risk factors such as age, sex, and comorbidities. To this end, characterising clinical phenotypes of PCC is essential for deepening our understanding of its (potentially) distinct pathophysiological mechanisms and for advancing diagnostic and patient-tailored management strategies. PCC is thought to result from a complex interaction of various pathophysiological mechanisms, leading to functional and structural pathological alterations across multiple organ systems. Investigating these alterations is critical to improving our currently incomplete understanding of PCC's complex pathophysiology. This review provides an overview of the main clinical phenotypes of PCC, characterises these phenotypes by examining symptoms and signs, as well as the associated risk factors. The main hypothesised pathophysiological mechanisms are discussed by outlining the current knowledge on PCC pathology, focussing on the most commonly affected organ systems. Current PCC management includes supportive care such as physiotherapy and the repurposing of existing drugs primarily targeting persistence of SARS-CoV-2 (e.g. antivirals, monoclonal antibodies) and immune dysfunction (e.g. antiinflammatory drugs, immunomodulators). To date, prevention of SARS-CoV-2 infection remains critical, which can be achieved through effective public health measures and vaccination strategies. Finally, this review highlights current knowledge gaps and proposes future research directions to advance the understanding and treatment of PCC. © 2025 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Long-Term Sequelae of COVID-19: A Systematic Review and Meta-Analysis of Symptoms 3 Years Post-SARS-CoV-2 Infection

The symptoms of long COVID are well-documented. However, the long-term effects beyond 2 years remain poorly understood due to a lack of data. This systematic review and meta-analysis examined the prevalence of persistent symptoms in COVID-19 survivors 3 years following initial SARS-CoV-2 infection. PubMed, MEDLINE (Ovid), CENTRAL, Web of Science, Scopus, and Embase were searched from inception of the databases up to July 20, 2024, by two independent researchers for articles reporting on the prevalence of persistent symptoms 3 years' post-infection of people who survived COVID-19 infection. We employed a random-effect model for the pooled analysis, and the meta-analytical effect size was prevalence for the applicable end-points, I2 statistics, and quality assessment of included studies using the Newcastle-Ottawa Scale. Eleven articles were included after the literature search yielded 223 potentially relevant articles. We found that among patients with long COVID, fatigue, sleep disturbances, and dyspnea were the most common symptoms. Pooled analysis showed that the proportion of individuals experiencing at least one persistent symptom 3 years post-COVID-19 is 20% (95% confidence interval [CI]: 8-43). The prevalence of persistent symptoms was dyspnea (12%; 95% CI: 10-15), fatigue (11%; 95% CI: 6-20), insomnia (11%; 95% CI: 2-37), loss of smell (7%; 95% CI: 5-8), loss of taste (7%; 95% CI: 3-16), and anxiety (6%; 95% CI: 1-32). Prevalence of other findings include impaired diffusion capacity (42%; 95% CI: 34-50) and impaired forced expiratory volume in 1 s (10%; 95% CI: 8-12). Our findings confirm the persistence of unresolved symptoms 3 years post-COVID-19 infection, with implications for future research, healthcare policy, and patient care.

A detailed examination of coronavirus disease 2019 (COVID-19): Covering past and future perspectives

The COVID-19 disease has spread rapidly across the world within just six months, affecting 169 million people and causing 3.5 million deaths globally (2021). The most affected countries include the USA, Brazil, India, and several European countries such as the UK and Russia. Healthcare professionals face new challenges in finding better ways to manage patients and save lives. In this regard, more comprehensive research is needed, including genomic and proteomic studies, personalized medicines and the design of suitable treatments. However, finding novel molecular entities (NME) using a standard or de novo strategy to drug development is a time-consuming and costly process. Another alternate strategy is discovering new therapeutic uses for old/existing/available medications, known as drug repurposing. There are a variety of computational repurposing methodologies, and some of them have been used to counter the coronavirus disease pandemic of 2019 (COVID-19). This review article compiles recently published data on the origin, transmission, pathogenesis, diagnosis, and management of the coronavirus by drug repurposing and vaccine development approach. We have attempted to screen probable drugs in clinical trials by using literature survey. This systematic review aims to create priorities for future research of drugs repurposed and vaccine development for COVID-19.

Personalisation at the Core of Success: Process Evaluation of the LISTEN Randomised Controlled Trial Evaluating a Personalised Self-Management Support Intervention for People Living With Long Covid

BACKGROUND

The development and evaluation of rehabilitation interventions designed to support people with Long Covid (LC) remains an important ongoing priority. Many people with LC experience episodic, debilitating symptoms that can reduce their ability to engage in all areas of activity. The Long CovId personalised Self-managemenT support co-design and EvaluatioN (LISTEN) trial co-designed and evaluated a personalised self-management support intervention to build confidence and support people to live better with LC. This paper describes the context, implementation, mechanisms of impact and impacts from the LISTEN intervention, in comparison with usual LC services accessed within the National Health Service (NHS).

METHODS

A mixed methods process evaluation was nested within the LISTEN pragmatic, multi-site, randomised controlled trial. Data were collected from sites in England and Wales between September 2022 and January 2024. Observations and focus groups with healthcare practitioners (HCPs) delivering the intervention were conducted to assess fidelity. Standardised implementation measures, focussed on intervention feasibility, acceptability and appropriateness, were gathered from HCPs and intervention participants. Semi-structured interviews were undertaken with a subset of participants across both trial arms. Data were analysed independently using descriptive statistics, or reflexive thematic analyses, and subsequently integrated, drawing upon the Consolidated Framework for Implementation Research v2.

FINDINGS

Thirty-six HCPs participated in the process evaluation, and 197 intervention participants completed standardised implementation measures. Across both trial arms, 49 participants took part in semi-structured interviews. Six integrated themes were constructed from all data sources describing and illustrating links between the context, implementation, mechanisms of impact and impacts: 'Delivery during uncertainty and ambiguity', 'Diversity and consistency of usual care', 'Drivers for self-care and the impact of self-generated expertise', 'Appropriate if unexpected support', 'Personalisation at the core of success' and 'A spectrum of change'.

CONCLUSION

The LISTEN intervention is an appropriate, feasible intervention for participants and HCPs. The intervention can be delivered to a high level of fidelity following training and with ongoing HCP support. Access, receipt and perceptions of NHS LC services were variable. Personalised, relational interventions, such as LISTEN, can foster favourable impacts on confidence, knowledge and activity and are acceptable and strongly recommended within LC rehabilitation services.

PATIENT OR PUBLIC CONTRIBUTION

The study was supported by a patient and public involvement and engagement (PPIE) group from project conception to study end. Using their lived expertise, seven people with LC supported accessible recruitment (e.g., materials), data collection (e.g., topic guides), data interpretation (e.g., theme construction and reviewing findings) and dissemination activities (e.g., online webinars).

TRIAL REGISTRATION

ISRCTN36407216, registered 27/01/2022.

Home Spirometry for Post-COVID Recovery: A Clinical Validation Study of an Ultrasonic Device

Background/Objectives: Patients recovering from COVID-19 often experience persistent respiratory symptoms, necessitating pulmonary function monitoring. While clinical spirometry is the gold standard, home spirometry offers a remote alternative. This study evaluated the validity of an ultrasonic home-based spirometer for monitoring lung function in post-COVID-19 pneumonia patients over 12 weeks. Methods: This prospective study included 30 post-COVID pneumonia patients who underwent clinical spirometry at weeks 4, 8 and 12. Participants performed weekly home spirometry using the SpiroHome Personal® device. Agreement between home and clinical spirometry was assessed using a Bland-Altman analysis, intraclass correlation coefficients (ICCs), and Pearson correlation coefficients. Pulmonary function changes over time were analyzed using repeated measures ANOVA. Results: Home spirometry showed strong agreement with clinical spirometry for forced vital capacity (FVC) and forced expiratory volume in the first second (FEV1), with ICC values exceeding 0.92. The Bland-Altman analysis demonstrated minimal bias, though limits of agreement exceeded the clinically accepted threshold of ±150 mL. FEV1/FVC ratios showed greater variability. Pulmonary function improved significantly over 12 weeks for both methods (p < 0.002). Patient adherence to home spirometry remained high, with a median of 18.50 sessions [IQR: 15.00-26.00] and an overall compliance rate of 98.33% ± 9.13%. Conclusions: Home spirometry provides reliable pulmonary function measurements, particularly for FVC and FEV1, supporting its role as a remote monitoring tool. Despite minor variability in FEV1/FVC, home spirometry enables frequent assessment of lung function recovery, potentially reducing hospital visits and improving patient management.

The Effect on Quality of Life of Therapeutic Plasmapheresis and Intravenous Immunoglobulins on a Population of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients with Elevated β-Adrenergic and M3-Muscarinic Receptor Antibodies-A Pilot Study

Background/Objectives: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating condition with not fully understood causes, though evidence points to immune system involvement and possible autoimmunity. ME/CFS could be triggered by various infectious pathogens, like SARS-CoV-2; furthermore, a subset of the post-COVID-19 condition (PCC) patients fulfill the diagnostic criteria of ME/CFS. According to the Canadian Consensus Criteria (CCC), the presence of specific symptoms such as fatigue, post-exertional malaise, sleep dysfunction, pain, neurological/cognitive manifestations, and symptoms from at least two of the following categories lead to the diagnosis of ME/CFS: autonomic, neuroendocrine, and immune manifestation. In this study, the patient selection was based on the identification of ME/CFS patients with elevated autoantibodies, regardless of the triggering factor of their condition. Methods: The aim of this study was to identify ME/CFS patients among long COVID patients with elevated autoantibodies. In seven cases, plasmapheresis (PE) and intravenous immunoglobulins (IVIGs) with repetitive autoantibody measurements were applied: four PE sessions on days 1, 5, 30, and 60, and a low-dose IVIG therapy after each treatment. Antibodies were measured before the first PE and two weeks after the last PE session. To monitor clinical outcomes, the following somatic and psychometric follow-up assessments were conducted before the first PE, 2 weeks after the second, and 2 weeks after the last PE: the Schellong test, ISI (insomnia), FSS (fatigue), HADS (depression and anxiety), and EQ-5D-5L (quality of life) questionnaires. Results: There was a negative association between both the β2-adrenergic and M3-muscarinic receptor autoantibody concentration and the quality of life measurements assessed with the EQ-5D-5L questionnaire. Per 1 U/mL increase in the concentration levels of β2-adrenergic receptor antibodies or M3-muscarinic acetylcholine receptor antibodies, the EQ-5D-5L index score [-0.59 to 1] decreased by 0.01 (0.63%) or 0.02 (1.26%), respectively. There were no significant associations between the ISI, HADS, and FSS questionnaires and the β1-adrenergic and M4-muscarinic receptor antibodies titers. Conclusions: After a thorough selection of patients with present autoantibodies, this pilot study found negative associations concerning autoantibody concentration and somatic, as well as psychological wellbeing. To validate these promising feasibility study results-indicating the potential therapeutic potential of antibody-lowering methods-further investigation with larger sample sizes is needed.

Beyond time as the healer: action in long COVID treatment to improve patient outcomes

Long COVID is complex and disabling. Despite emerging therapies, the lack of guidelines and clinician awareness delays treatment. This paper highlights options available now to improve function and quality of life. We call for a symptom-focused, person-centred approach that incorporates lived experience and clinical judgement to bridge the gap between evidence and care. Time alone is not the answer.

Deletion of the Envelope gene attenuates SARS-CoV-2 infection by altered Spike localization and increased cell-to-cell transmission

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19, a highly transmissible acute respiratory infection that can result in severe pneumonia and death. Many details of SARS-CoV-2 infection are not fully understood, including the cell biology and host-virus interactions involved in coronavirus assembly and release, in which the Envelope (E) structural protein is instrumental. Deletion of E in other coronaviruses has been shown previously to either attenuate or abrogate infection. To determine the role of E on SARS-CoV-2 virus production and infectivity, we produced reporter SARS-CoV-2 with or without the E gene deleted using a bacterial artificial chromosome. Replication of ΔE SARS-CoV-2 was attenuated in Vero E6 cells expressing human ACE2 and TMPRSS2 and in human epithelial cell lines. Electron and immunofluorescence microscopy and virology assays showed that ΔE SARS-CoV-2 increased cell surface expression of Spike (S) glycoprotein, leading to reduced S incorporation into ΔE SARS-CoV-2 particles and promotion of increased cell-to-cell transmission that evades neutralizing antibody inhibition. Trans-complementation of E partially rescued ΔE SARS-CoV-2 S incorporation and restored cell-free transmission. In addition to validating the role of E in retention of S in the ER-Golgi intermediate complex (ERGIC), our results showed that a lack of E led to reorganization of the ERGIC during SARS-CoV-2 infection. Improved understanding of E in SARS-CoV-2 replication and host pathogenesis may help development of novel therapeutics.

Importance

Non-S coronavirus structural proteins, including E, are conserved, making them potential pan-coronavirus therapeutic targets. Many details about these proteins and their roles in viral replication and host pathogenesis are unknown. In this study, we showed that SARS-CoV-2 replicates without E but is attenuated and impaired for virus particle formation, with less S incorporated into virions and more S expressed on the cell surface compared to wild-type virus. SARS-CoV-2 lacking E spread primarily via cell fusion and evaded neutralizing antibodies. In addition, the absence of E resulted in the reorganization of the ERGIC cell secretory compartment during SARS-CoV-2 infection. A better understanding of how E influences SARS-CoV-2 replication could guide directed design of novel therapeutics for treatment of COVID-19 patients, as well as the potential for pan-coronavirus protection against future coronavirus outbreaks.

Burden of Selected Chronic Conditions Among Adults of Prime Working Age (25-54) by 2022 Self-Reported COVID-19 and Long COVID History Compared to 2019 Pre-Pandemic Baseline Prevalence: Behavioral Risk Factor Surveillance System

INTRODUCTION

Prior research has observed increased risks for numerous chronic conditions among individuals with Long COVID. Chronic conditions have been associated with employment limitations and increased economic hardships. Data from the Behavioral Risk Factor Surveillance System (BRFSS) present an opportunity to examine changes by employment status in the prevalence of a range of chronic conditions between 2019 (pre-pandemic) and, in 2022, by self-reported COVID-19 or Long COVID.

METHODS

We assessed the prevalence of chronic conditions in 2022 by employment status and self-reported COVID-19 and Long COVID history using data from BRFSS for adults of prime working age (25-54 years) who were employed for wages, self-employed, unemployed less than 1 year, unemployed 1 year or more, or unable to work. For each chronic condition (coronary heart disease and myocardial infarction [combined], stroke, ever and current asthma, chronic obstructive pulmonary disease, kidney disease, diabetes, and arthritis), we generated adjusted prevalence ratios (aPRs) comparing 2022 prevalence by COVID-19/Long COVID category to prevalences among respondents in that employment status before the pandemic (2019).

RESULTS

The prevalence of both asthma and diabetes increased significantly between 2019 and 2022 among respondents in all included employment categories and COVID-19/Long COVID histories combined. Among employed respondents with Long COVID in 2022, aPRs using 2019 prevalence figures for all employed respondents as a baseline for comparison had statistically significant elevations for every chronic condition assessed.

CONCLUSIONS

The increased prevalence of a range of chronic conditions between 2019 and 2022 among adults with Long COVID may present a burden for individuals, the workplace, the healthcare system, and the economy. Additional research in a longitudinal context could better quantify these associations. Efforts to prevent, identify, and treat Long COVID can reduce this burden.

Utilizing Google Trends data to enhance forecasts and monitor long COVID prevalence

BACKGROUND

Long COVID, the persistent illness following COVID-19 infection, has emerged as a major public health concern since the outbreak of the pandemic. Effective disease surveillance is crucial for policymaking and resource allocation.

METHODS

We investigated the potential of utilizing Google Trends data to enhance long COVID symptoms surveillance. Though Google Trends provides freely available search popularity data, limitations in data normalization and retrieval restrictions have hindered its predictive capabilities. In our study, we carefully selected 33 search terms and 20 related topics from the long COVID symptoms list provided by the Centers for Disease Control and Prevention and the database "scite", and calculated their merged search volumes from Google Trends data using our developed statistical method for analysis.

RESULTS

We identify four related topics (ageusia, anosmia, chest pain, and headaches) that consistently exhibit increased search popularity before that of "long COVID." Additionally, nine related topics (aching muscle pain, anxiety, chest pain, clouding of consciousness, dizziness, fatigue, myalgia, shortness of breath, and hypochondriasis) show increased search popularity following that of "long COVID." We demonstrate that the merged search volume (MSV), derived from the relative search volume data downloaded from Google, can be used to forecast the prevalence of long COVID in a prediction study, supporting the use of the methodology in risk management regarding the prevalence of long COVID.

CONCLUSIONS

By utilizing a comprehensive list of search terms and sophisticated statistical analytics, our study contributes to exploring the potential of Google Trends data for forecasting and monitoring long COVID prevalence. These findings and methodologies can be used as prior knowledge to inform future infodemiological and epidemiological investigations.

Self-reported health, neuropsychological tests and biomarkers in fully recovered COVID-19 patients vs patients with post-COVID cognitive symptoms: A pilot study

Substantial numbers of individuals who contract COVID-19 experience long-lasting cognitive symptoms such as brain fog. Yet research to date has not compared these patients with healthy controls with a history of laboratory-confirmed COVID-19 infection, making it difficult to understand why certain COVID patients develop post-COVID cognitive symptoms while others do not. The objective of this pilot study was to compare two groups of laboratory-confirmed post-COVID patients, with and without cognitive symptoms, on measures of cognitive and psychological functioning, self-reported perceptions of functional status and quality of life, and biomarkers of stress, inflammation, and neuroplasticity. Using a case-control design, 17 participants were recruited from a healthcare system in western Michigan, USA in 2022-2024. All participants were aged 25-65 and had a positive polymerase chain reaction (PCR) test confirming previous COVID-19 infection. Ten participants reported cognitive symptoms (long COVID group) while seven were fully recovered with no residual symptoms (controls). All participants underwent an interview on their self-rated health and quality of life, a battery of neurocognitive tests, and blood draw for biomarker analysis. No group differences were detected for neuropsychological test measures except for letter fluency where the long COVID group scored significantly lower (p < .05). The long COVID group had significantly lower ratings than controls on quality of life, physical health, emotional functioning, and psychological well-being. Serum levels of nerve growth factor (NGF), a biomarker of brain plasticity, were significantly lower in the long COVID group, which was significantly more likely than controls to have serum levels of inflammatory marker (interleukin (IL)-10) values greater than or equal to the median (p = 0.015). Biomarker analyses suggest possible prolonged inflammatory processes in long COVID patients compared to fully recovered patients. Results of decreased neuroplastic functioning give credence to patients' reports of post-COVID changes in brain function.

A review of the sequelae of post Covid-19 with neurological implications (post-viral syndrome)

Post Covid-19 conditions represent a medical challenge; a unified definition is not achieved after 5 years of the Pandemic. The incidence of Post Covid-19 conditions varies, nevertheless the neurological complications represent an important aspect in the spectrums of fields involved. The current perception is that varied manifestations and long-term complications of COVID-19 reflect underlying pathophysiological processes, including inflammatory, immune-mediated, and vascular mechanisms. These mechanisms underscore the complexity of COVID-19's impact including the nervous system and its potential for lasting effects. A number of symptoms are extremely severe and may also need neurologic attention including fatigue, cognitive disturbances, autonomic symptoms, headache, and sleep disorders. Post Covid-19 conditions are often of chronic nature. Management as in other chronic conditions should rely on the conventional diagnostic measures and management of symptoms irrespective of the temporal relation to the viral infection. To date Post Covid-19 conditions is only accepted as an additional or explanatory diagnosis.

Reproducibility of genetic risk factors identified for long COVID using combinatorial analysis across US and UK patient cohorts with diverse ancestries

BACKGROUND

Long COVID is a major public health burden causing a diverse array of debilitating symptoms in tens of millions of patients globally. In spite of this overwhelming disease prevalence, staggering cost, severe impact on patients' lives and intense global research efforts, study of the disease has proved challenging due to its complexity. Genome-wide association studies (GWAS) have identified only four loci potentially associated with the disease, although these results did not statistically replicate between studies. A previous combinatorial analysis study identified a total of 73 genes that were highly associated with two long COVID cohorts in the predominantly (> 91%) white European ancestry Sano GOLD population, and we sought to reproduce these findings in the independent and ancestrally more diverse All of Us (AoU) population.

METHODS

We assessed the reproducibility of the 5343 long COVID disease signatures from the original study in the AoU population. Because the very small population sizes provide very limited power to replicate findings, we initially tested whether we observed a statistically significant enrichment of the Sano GOLD disease signatures that are also positively correlated with long COVID in the AoU cohort after controlling for population substructure.

RESULTS

For the Sano GOLD disease signatures that have a case frequency greater than 5% in AoU, we consistently observed a significant enrichment (77-83%, p < 0.01) of signatures that are also positively associated with long COVID in the AoU cohort. These encompassed 92% of the genes identified in the original study. At least five of the disease signatures found in Sano GOLD were also shown to be individually significantly associated with increased long COVID prevalence in the AoU population. Rates of signature reproducibility are strongest among self-identified white patients, but we also observe significant enrichment of reproducing disease associations in self-identified black/African-American and Hispanic/Latino cohorts. Signatures associated with 11 out of the 13 drug repurposing candidates identified in the original Sano GOLD study were reproduced in this study.

CONCLUSION

These results demonstrate the reproducibility of long COVID disease signal found by combinatorial analysis, broadly validating the results of the original analysis. They provide compelling evidence for a much broader array of genetic associations with long COVID than previously identified through traditional GWAS studies. This strongly supports the hypothesis that genetic factors play a critical role in determining an individual's susceptibility to long COVID following recovery from acute SARS-CoV-2 infection. It also lends weight to the drug repurposing candidates identified in the original analysis. Together these results may help to stimulate much needed new precision medicine approaches to more effectively diagnose and treat the disease. This is also the first reproduction of long COVID genetic associations across multiple populations with substantially different ancestry distributions. Given the high reproducibility rate across diverse populations, these findings may have broader clinical application and promote better health equity. We hope that this will provide confidence to explore some of these mechanisms and drug targets and help advance research into novel ways to diagnose the disease and accelerate the discovery and selection of better therapeutic options, both in the form of newly discovered drugs and/or the immediate prioritization of coordinated investigations into the efficacy of repurposed drug candidates.

Exploring the presence of long COVID-like symptoms in patients with chronic pain: a large-scale internet-based cross-sectional study in Japan

ABSTRACT

Individuals with chronic pain not only endure the direct burden of pain but also experience various symptoms, including sleep disturbances and fatigue, which deteriorate their quality of life. Notably, these symptoms closely resemble those observed in "long COVID," a prolonged health complication that can arise after coronavirus disease 2019 (COVID-19) infection. Because the similarities between chronic pain and long COVID remain unexplored, this study aimed to investigate their relationship using Japanese epidemiological data. Using the Japan COVID-19 and Society Internet Survey in 2022, which included 32,000 participants, we analyzed data on the presence of chronic pain, history of COVID-19 infection, and presence of 17 long COVID-like symptoms, including gastrointestinal upset, back pain, limb/joint pain, headache, chest pain, shortness of breath, dizziness, sleep disorder, hearing disorder, taste disorder, smell disorder, memory impairment, poor concentration, hair loss, decreased libido, fatigue, and cough. Individuals with history of COVID-19 experienced a significantly greater number of long COVID-like symptoms (median: 5) compared with those with neither COVID-19 nor chronic pain (median: 4, P < 0.001). Individuals with chronic pain alone and those with both COVID-19 and chronic pain exhibited an even greater number of symptoms (median: 8 and 9, respectively). In addition, individuals with chronic pain exhibited greater prevalence odds for 15 of the 17 symptoms than those with neither COVID-19 nor chronic pain (P < 0.001). Our findings indicate that long COVID-like symptoms are not specifically associated with COVID-19. Instead, the data suggest that chronic pain contributes as an independent risk factor for these symptoms.

Post-acute sequelae of COVID-19 in residents in long-term care homes: Examining symptoms and recovery over time

BACKGROUND

Post-COVID-19 condition (PCC) has been studied extensively since the inception of the COVID-19 pandemic. In the population of long-term care (LTC) home residents, however, information about PCC and recovery after the acute phase of COVID-19 is lacking. This study contributes evidence about symptoms over time in 459 residents in nine Canadian LTC homes.

METHODS

In a comprehensive retrospective chart review, we recorded medical symptoms in a 4-week period before contracting COVID-19 ("PRE-COVID") and during 24 weeks after contracting infection (a 4-week "ACUTE-COVID" period and five subsequent 4-week periods "POST1-5"). We investigated the number and type of symptoms over time, examined different "recovery trajectories", and compared the characteristics of residents across different trajectories.

RESULTS

In the sample overall, the number of different symptoms increased from PRE-COVID to ACUTE-COVID (mean difference of 3 symptoms, p<.001), returning to the PRE-COVID level within the first two months post-infection. An individual-level examination revealed that after ACUTE-COVID about a quarter of residents did not return to their symptom baseline. There was no statistically significant difference in demographic characteristics or PRE-COVID comorbidities across different recovery trajectories. Comparing the group of residents that did not return to their symptom baseline and the group that did, the risk for not returning to baseline increased with the number of symptoms in ACUTE-COVID (adjusted for age, sex, and PRE-COVID comorbidities, exp[B]=1.15, 95% CI [1.05;1.25], p=.002). Additionally, there was a greater increase in the number of symptoms from PRE-COVID to ACUTE-COVID in the former group (significant interaction effect, p<.001). We present symptom types in each time-period.

CONCLUSIONS

Group-level results indicated that the number of symptoms after contracting COVID-19 fell to the pre-COVID level within the first two months post-infection. An examination of individual-level symptom trajectories contributed a more granular picture of recovery after infection and characteristics of residents across different trajectories.

Targeting the SARS-CoV-2 reservoir in long COVID

There are no approved treatments for post-COVID-19 condition (also known as long COVID), a debilitating disease state following SARS-CoV-2 infection that is estimated to affect tens of millions of people. A growing body of evidence shows that SARS-CoV-2 can persist for months or years following COVID-19 in a subset of individuals, with this reservoir potentially driving long-COVID symptoms or sequelae. There is, therefore, an urgent need for clinical trials targeting persistent SARS-CoV-2, and several trials of antivirals or monoclonal antibodies for long COVID are underway. However, because mechanisms of SARS-CoV-2 persistence are not yet fully understood, such studies require important considerations related to the mechanism of action of candidate therapeutics, participant selection, duration of treatment, standardisation of reservoir-associated biomarkers and measurables, optimal outcome assessments, and potential combination approaches. In addition, patient subgroups might respond to some interventions or combinations of interventions, making post-hoc analyses crucial. Here, we outline these and other key considerations, with the goal of informing the design, implementation, and interpretation of trials in this rapidly growing field. Our recommendations are informed by knowledge gained from trials targeting the HIV reservoir, hepatitis C, and other RNA viruses, as well as precision oncology, which share many of the same hurdles facing long-COVID trials.

Suitability of just-in-time adaptive intervention in post-COVID-19-related symptoms: A systematic scoping review

Patients with post-COVID-19-related symptoms require active and timely support in self-management. Just-in-time adaptive interventions (JITAI) seem promising in meeting these needs, as they aim to provide tailored interventions based on patient-centred measures. This systematic scoping review explores the suitability and examines key components of a potential JITAI in post-COVID-19 syndrome. Databases (PsycINFO, PubMed, and Scopus) were searched using terms related to post-COVID-19-related symptom clusters (fatigue and pain; respiratory problems; cognitive dysfunction; psychological problems) and to JITAI. Studies were summarised to identify potential components (interventions options, tailoring variables and decision rules), feasibility and effectiveness, and potential barriers. Out of the 341 screened records, 11 papers were included (five single-armed pilot or feasibility studies, three two-armed randomised controlled trial studies, and three observational studies). Two articles addressed fatigue or pain-related complaints, and nine addressed psychological problems. No articles about JITAI for respiratory problems or cognitive dysfunction clusters were found. Most interventions provided monitoring, education or reinforcement support, using mostly ecological momentary assessments or smartphone-based sensing. JITAIs were found to be acceptable and feasible, and seemingly effective, although evidence is limited. Given these findings, a JITAI for post-COVID-19 syndrome is promising, but needs to fit the complex, multifaceted nature of its symptoms. Future studies should assess the feasibility of machine learning to accurately predict when to execute timely interventions.

Evaluation of long-term changes in liver function and structure in patients exposed to SARS-CoV-2 infection: A prospective study

BACKGROUND & AIMS

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) binds to Angiotensin Converting Enzyme - 2 (ACE2) receptor targeting various organs including liver. Liver injury is a common feature of SARS-CoV-2 acute infection. A few studies have also described chronic hepatic alterations in patients with previous COVID-19. We hypothesize that steatosis seen in COVID-19 patients reflects their metabolic profile and is not caused by persistent inflammation sustained by SARS-CoV-2.

METHODS

We conducted a prospective study to evaluate long-term changes in liver function and structure in patients hospitalized for COVID-19. Patients without a prior known hepatic disease with mild to moderate COVID-19 were enrolled during hospitalization and reevaluated during a follow-up visit at a medium 16 months. Complete blood panels with metabolic profile, BMI, alcohol consumption and physical activity were compared between baseline and follow-up. Specific ultrasound scans were obtained during hospital stay and at follow-up to quantify steatosis using Steatoscore2.0.

RESULTS

Among 55 eligible patients, 33 were included in the analysis and only 3 (9 %) had a new diagnosis of steatosis at follow-up. Steatoscore2.0 did not change significantly from baseline to follow-up (1.7 vs 1.73, p = 0.348), while changes occurred in body mass index and physical activity estimated by IPAQ questionnaire (26.3 vs 26.6 kg/m2, p = 0.005; 540 vs. 480, p = 0.015, respectively). There was a statistically significant increase in total cholesterol (144.5 vs 187.0 mg/dl, p = 0.003) and low-density lipoprotein-cholesterol (73.8 vs 113.9 mg/dl, p = 0.003). Inflammatory markers normalized at follow-up, including C-reactive protein (41.1 vs. 0.8 mg/L, p < 0.001), and ferritin (410.0 vs. 91.0 ng/dl, p < 0.001). Four patients had a 3-time rise in liver transaminase levels at baseline, and this was not confirmed at follow-up. Change in Steatoscore2.0 correlated significantly with Triglyceride-glucose index as a surrogate of insulin resistance.

CONCLUSIONS

In our study, long term functional and structural changes were not observed in patients with previous SARS-CoV-2 infection. There was a significant deterioration of metabolic profile post COVID-19.

Using machine learning involving diagnoses and medications as a risk prediction tool for post-acute sequelae of COVID-19 (PASC) in primary care

BACKGROUND

The aim of our study was to determine whether the application of machine learning could predict PASC by using diagnoses from primary care and prescribed medication 1 year prior to PASC diagnosis.

METHODS

This population-based case-control study included subjects aged 18-65 years from Sweden. Stochastic gradient boosting was used to develop a predictive model using diagnoses received in primary care, hospitalization due to acute COVID- 19, and prescribed medication. The variables with normalized relative influence (NRI) ≥ 1% showed were considered predictive. Odds ratios of marginal effects (ORME) were calculated.

RESULTS

The study included 47,568 PASC cases and controls. More females (n = 5113) than males (n = 2815) were diagnosed with PASC. Key predictive factors identified in both sexes included prior hospitalization due to acute COVID- 19 (NRI 16.1%, ORME 18.8 for females; NRI 41.7%, ORME 31.6 for males), malaise and fatigue (NRI 14.5%, ORME 4.6 for females; NRI 11.5%, ORME 7.9 for males), and post-viral and related fatigue syndromes (NRI 10.1%, ORME 21.1 for females; NRI 6.4%, ORME 28.4 for males).

CONCLUSIONS

Machine learning can predict PASC based on previous diagnoses and medications. Use of this AI method could support diagnostics of PASC in primary care and provide insight into PASC etiology.

Comparison of quadriceps muscle strength, functional capacity and fatigue at hospital discharge and after 12 months in COVID-19 hospitalized patients undergoing early rehabilitation: a follow-up study

PURPOSE

To compare quadriceps muscle strength, functional capacity, and fatigue at hospital discharge and after 12 months in hospitalized individuals with coronavirus disease 2019 (COVID-19) who underwent early rehabilitation, and to verify whether quadriceps muscle strength at hospital discharge and functional capacity at 12 months later could be correlated.

METHODS

This was a prospective cohort study. Isometric quadriceps muscle strength, the Short Physical Performance Battery (SPPB), and the Checklist Individual Strength (CIS) scale were assessed at discharge and after 12 months.

RESULTS

Of the 34 individuals, 17 completed the 12-month follow-up. Although the quadriceps muscle strength significantly improved (p = 0.046), 59.0% of individuals stayed below 70% of predicted values. SPPB score also significantly improved (p = 0.001), but some individuals still demonstrated moderate to low performance. CIS scale score did not change. Quadriceps muscle strength at discharge was correlated with the SPPB score 12 months later (r = 0.675; p = 0.006) and explained 45.6% of the variance in SPPB after 12 months (R2=0.456; p = 0.006).

CONCLUSION

Quadriceps muscle strength and SPPB score improved 12 months after hospital discharge due to COVID-19. However, some individuals still present impairments. Moreover, quadriceps muscle strength at discharge explained functional capacity after 12 months. Thus, early rehabilitation is essential for functional improvement.

Environmental exposures and familial background alter the induction of neuropathology and inflammation after SARS-CoV-2 infection

Post-infection sequela of several viruses have been linked with Parkinson's disease (PD). Here, we investigated whether mice infected with SARS-CoV-2 alone or in combination with two putative Parkinsonian toxins, MPTP and paraquat, increased the susceptibility to develop Parkinsonian pathology. We also examined if G2019S LRRK2 mice had any change in sensitivity to SARS-CoV-2 as well as if vaccination against this virus altered any neuropathology. Infection with WA-1/2020 or Omicron B1.1.529 strains sensitized both WT and G2019S LRRK2 mice to the neuropathological effects of a subtoxic exposure to MPTP, but not paraquat. These neuropathologies were rescued in WT mice vaccinated with mRNA- or protein-based SARS-CoV-2 vaccines. However, G2019S LRRK2 mutant mice were only protected with the protein-based vaccine. These results highlight the role of both environmental exposures and familial background on the development of Parkinsonian pathology secondary to viral infection and the benefit of vaccines in reducing these risks.

Post-exertional malaise in Long COVID: subjective reporting versus objective assessment

Background

Post-exertional malaise (PEM) is a central feature of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and has emerged as a prominent feature of Long COVID. The optimal clinical approach to PEM is inconclusive, and studies of the impact of exercise have yielded contradictory results.

Objective

The objective of this study was to examine PEM in Long COVID by assessing the prevalence of self-reported PEM across study cohorts and symptom responses of Long COVID patients to a standardized exercise stressor. Secondarily, Long COVID symptom responses to exercise were compared to those of ME/CFS and healthy volunteers.

Methods

Data from three registered clinical trials comprised four cohorts in this study: Long COVID Questionnaire Cohort (QC; n = 244), Long COVID Exercise Cohort (EC; n = 34), ME/CFS cohort (n = 9), and healthy volunteers (HV; n = 9). All cohorts completed questionnaires related to physical function, fatigue, and/or PEM symptoms. EC also performed a standardized exercise test (cardiopulmonary exercise test, CPET), and the PEM response to CPET was assessed using visual analog scales and qualitative interviews (QIs) administered serially over 72 h. EC PEM measures were compared to ME/CFS and HV cohorts. A secondary analysis of QI explored positive responses to CPET among EC, ME/CFS and HV.

Results

Self-reported PEM was 67% in QC and estimated at 27% in EC. Only 2 of 34 EC patients (5.9%) were observed to develop PEM after a CPET. In addition, PEM responses after CPET in Long COVID were not as severe and prolonged as those assessed in ME/CFS. Twenty-two of 34 EC patients (64.7%) expressed at least one of 7 positive themes after the CPET.

Conclusion

Self-report of PEM is common in Long COVID. However, observable PEM following an exercise stressor was not frequent in this small cohort. When present, PEM descriptions during QI were less severe in Long COVID than in ME/CFS. Positive responses after an exercise stressor were common in Long COVID. Exercise testing to determine the presence of PEM may have utility for guiding clinical management of Long COVID.

The Involvement and Manifestations of SARS-CoV-2 Virus in Cardiovascular Pathology

Although the acute phase of the COVID-19 pandemic has subsided, the emergence of the post-COVID-19 condition presents a new and complex public health challenge, characterized by persistent, multisystem symptoms that can endure for weeks or months after the initial infection with the SARS-CoV-2 virus, significantly affecting survivors' quality of life. Among the most concerning sequelae are cardiovascular complications, which encompass a broad spectrum of conditions, including arrhythmias, myocardial damage, or postural orthostatic tachycardia syndrome. This narrative review explores the burden of the SARS-CoV-2 infection on cardiovascular health by reviewing the latest and most relevant findings in the literature and highlighting different aspects of COVID-19's cardiovascular involvement. This review investigates the pathophysiological mechanisms underlying cardiovascular involvement in the post-COVID-19 condition, with a focus on direct viral invasion via ACE2 receptors, immune-mediated cardiovascular injury, cytokine storm, systemic inflammation, endothelial dysfunction, and mitochondrial injury. The interplay between pre-existing cardiovascular diseases, such as hypertension, atherosclerosis, diabetes, and atrial fibrillation, and COVID-19 is also explored, revealing that individuals with such conditions are at heightened risk for both severe acute illness and long-term complications. Long-term immune activation and the persistence of viral antigens are increasingly recognized as contributors to ongoing cardiovascular damage, even in individuals with mild or asymptomatic initial infections. As the healthcare system continues to adapt to the long-term consequences of the SARS-CoV-2 pandemic, a deeper understanding of these cardiovascular manifestations is essential. This knowledge will inform the development of targeted strategies for prevention, clinical management, and rehabilitation of affected patients. Furthermore, the insights gained from the intersection of COVID-19 and cardiovascular health will be instrumental in shaping responses to future viral epidemics, highlighting the necessity for multidisciplinary approaches to patient care and public health preparedness.

Ten sessions of hyperbaric oxygen versus sham treatment in patients with long covid (HOT-LoCO): a randomised, placebo-controlled, double-blind, phase II trial

OBJECTIVES

To evaluate if 10 sessions of hyperbaric oxygen treatments (HBOTs) improve short- and long-term health related quality of life, symptoms and physical performance in long covid patients compared with placebo.

DESIGN

Parallel, randomised, placebo-controlled, double-blind trial.

SETTING

Single-centre, university hospital, Sweden.

PARTICIPANTS

Previously healthy subjects aged 18-60 years, diagnosed with long covid were included. We excluded pregnant women, patients with RAND-36 (role limitations due to physical health (RP) and physical functioning (PF)) above 70, diabetes, hypertension and contraindications for HBOT.

INTERVENTIONS

Subjects were randomly assigned to 10 sessions of HBOT or sham (placebo) treatments over 6 weeks. HBOT involved 100% oxygen, 2.4 bar, 90 min, placebo medical air, 1.34-1.2 bar. Randomisation (1:1) was done electronically, in blocks stratified by sex and disease severity. Subjects and investigators were blinded to allocation.

PRIMARY AND SECONDARY OUTCOME MEASURES

Primary endpoints were changes from baseline in RAND-36 PF and RP at 13 weeks. Efficacy was analysed on an intention-to-treat basis. Harms were evaluated according to the actual treatment given.

RESULTS

Between 15 September 2021 and 20 June 2023, 80 subjects (65 women, 15 men) were enrolled and randomised (40 in each group). The trial is completed. The primary endpoint analysis included 79 subjects (40 in HBOT and 39 in control). At 13 weeks, both groups showed improvement, with no significant difference between HBOT and placebo in PF (least square mean difference between groups (LSD), 0.63 (95% CI -7.04 to 8.29), p=0.87) and RP (LSD, 2.35 (95% CI -5.95 to 10.66), p=0.57).

HARMS

43 adverse events (AEs), most commonly cough and chest pain/discomfort, occurred in 19 subjects (49%) of the HBOT group and 38 AEs in 18 subjects (44%) of the placebo group, one serious AE in HBOT and one death in the placebo group.

CONCLUSIONS

10 HBOT sessions did not show more short-term benefits than placebo for long covid patients. Both groups improved, with a notable sex difference. HBOT has a favourable harm profile.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov (NCT04842448), EudraCT (2021-000764-30). The trial was funded by Vetenskapsrådet (2022-00834), Region Stockholm (2020-0731, 2022-0674), Hjärt-Lungfonden and OuraHealth Oy.

D, Narreddy S, Gowri S. M, Rupali P, Sathyendra S. Prevalence and predictors of long COVID at 1 year in a cohort of hospitalized patients: A multicentric qualitative and quantitative study

INTRODUCTION

According to WHO long COVID is defined as a continuation or development of new symptoms 3 months after the initial SARS-CoV-2 infection, with these symptoms lasting for at least 2 months with no other explanation. We followed up patients after an episode of acute COVID-19 for 1 year after hospital discharge from different parts of India.

METHODS

This was a multi-centric study among patients ≥18 years hospitalized with COVID-19, which recruited patients at 6 weeks after hospital discharge (baseline). Quantitative data on demographics, pre-existing co-morbidities, risk factors, signs and symptoms and hospital parameters during acute COVID-19 infection were noted at baseline. They were followed up and data collected telephonically thereafter at 3-6, 6-9 and 9-12 months regarding self-reported persistence of symptoms. A qualitative component included face to face in-depth interviews to elicit information on perceived health problems, quality of life and financial burden due to COVID-19.

RESULTS

A total of 315 patients were enrolled, with the majority being males (59.4%). The median age was 52 years (IQR 40, 63). The prevalence of long COVID was 16.5%. At 6 weeks and 12 months, 35.2% and 25.9% of patients, reported more than one new symptom that affected their quality of life. Shortness of breath was common at each time point, persistent muscle pain and weakness waxed and waned. Variables at 6 weeks post discharge (baseline) such as shortness of breath (OR 2.22 CI 1.06-4.65, p = <0.05), cough (OR 6.93, CI 2.36-20.30, p = <0.05), fatigue (OR 2.34, CI 1.05-5.23, p = <0.05), and weight loss (OR 2.90, CI 1.30-6.49, p = <0.05) were significantly associated with long COVID.

CONCLUSION

We found that long COVID was noted in 16.5% patients who self reported non - recovery at 1 year. Physical symptoms, mental health issues and mobility were persistent in a significant number of patients following an initial recovery from an acute COVID-19 infection. In 25.9% of patients more than 1 symptom was reported at 1 year after COVID-19. We urgently need therapeutic interventions which can improve the quality of life in these patients.

Cumulative social disadvantage and its impact on long COVID: insights from a U.S. national survey

BACKGROUND

The COVID-19 pandemic has exacerbated health disparities, with long COVID emerging as a major global public health challenge. Although clinical risk factors for long COVID are well-documented, the cumulative burden of adverse social determinants of health (SDoH) remains underexplored. This study aims to investigate the association between cumulative social disadvantage and long COVID.

METHODS

Using data from the 2022 and 2023 National Health Interview Survey cycles (n = 16,446 U.S.adults), cumulative social disadvantage was quantified through 18 SDoH indicators and categorized into quartiles. The highest quartile represents the most disadvantaged individuals. Long COVID was defined as self-reported symptoms persisting for three months or longer. Weighted logistic regression models were used to examine the association, adjusting for demographic and clinical variables.

RESULTS

Adults in the highest quartile of cumulative social disadvantage exhibited an increased odds of experiencing long COVID compared to those in the lowest quartile (AOR = 2.52, 95% Cl: 2.13, 2.98). This association persisted across demographic subgroups, with particularly pronounced effects among women and non-Hispanic Blacks. Hispanics and non-Hispanic Whites showed weaker, but still statistically significant. Key contributors included mental health difficulties, economic instability, and healthcare access barriers. Furthermore, cumulative social disadvantage was linked to fair or poor general health status among individuals with long COVID.

CONCLUSIONS

This study highlights the positive association between cumulative social disadvantage and long COVID. Addressing systemic inequities through integrated public health strategies is essential to mitigate the burden of long COVID and reduce social disparities in health.

Pulmonary and functional hallmarks after SARS-CoV-2 infection across three WHO severity level-groups: an observational study

Background

The manifestations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection range from flu-like symptoms to severe lung disease. The consequences of this inflammatory process impact overall function, which can be detected through both short- to long-term assessments. This study aimed to assess the pulmonary functional and structural characteristics of post-SARS-CoV-2 infection in patients with mild/moderate, severe, and critical clinical presentations.

Methods

An observational, analytical, and cross-sectional study was conducted between 2020 and 2022, including participants with a confirmed diagnosis of coronavirus disease (COVID)-19, with mild/moderate (G1), severe (G2), and critical (G3) clinical presentations, all evaluated at least 3 months after acute infection. Spirometry, impulse oscillometry, fractional exhaled nitric oxide (FeNO), chest computed tomography, the 6-min walk test (6MWT), hand grip strength, maximum inspiratory pressure, and maximum expiratory pressure were assessed.

Results

We enrolled 210 participants aged 18-70 years, 32.6% of whom were male, with older age observed in G3. The participants were grouped as follows: G1 (42.3%), G2 (25.7%), and G3 (31.9%). Percentage of predicted X5 differed between G1 and G2, being higher in G1. The percentage of predicted forced vital capacity (FVC) according to the Global Lung Function Initiative and its z-score were higher in G1. The FVC by Pereira was lower in G3 compared to G1. The percentage of predicted forced expiratory volume in 1 s (FEV1) by Pereira was also lower in G3. The Tiffeneau (FEV1/FVC) index was different among groups, increasing with disease severity. The percentage of predicted forced expiratory flow rate at 25-75% (FEF25-75%) of the FVC and FeNO were both higher in G2 than G1. Chest computed tomography revealed the presence of interstitial abnormalities, associated with disease severity. The respiratory muscle strength evaluation showed an association between higher maximum expiratory pressure values in G3 compared to G1, but no association with maximum inspiratory pressure was observed. The 6MWT distance covered decreased with increasing severity, with a lower percentage of predicted values in G3 compared to G1. The right-hand grip strength was also lower in G3 compared to G1.

Conclusion

Alterations in pulmonary and functional markers were observed in post-COVID-19 evaluations, increasing with disease severity, as seen in G2 and G3. These findings highlight the complexity of post-COVID-19 functional assessments, given the long-term pulmonary sequelae and the consequent impairment of functional capacity.

Rethinking the evidence on COVID-19 in Africa

The COVID-19 pandemic was predicted to cause substantial mortality in Africa. However, some countries in Africa had a striking absence of overwhelmed hospitals and low reported mortality. The marked contrast with the overwhelmed hospitals and high mortality seen in Europe and other high-income settings was regarded as puzzling and a paradox. In this Review, we reflect on possible explanations for the paradox with particular reference to observations made on the ground in Kenya. The evidence is inconsistent with reduced viral transmission or poor surveillance as primary explanations for the discrepancy. Population age structure is an important but incomplete explanation of the epidemiology. Due to the high prevalence of asymptomatic infection, low mortality, and evidence of reduced inflammatory responses, we hypothesise that some populations in Africa might have reduced susceptibility to symptomatic COVID-19. The reduced inflammatory responses might result from immunoregulation or cross-reactive, pre-pandemic cellular immunity, although the evidence is not definitive. Local data are essential to develop public health policies that align with the reality on the ground rather than external perceptions.

Patient Perspectives on the Care in a Long COVID Outpatient Clinic-A Regional Qualitative Analysis from Germany

Background/Objectives: Long COVID specialized outpatient clinics (sOCs), which are part of the recommended long COVID care, usually face high demand. Few studies focused on the experience of care in such facilities in Germany. This study investigated how patients experience care in a sOC at a German university hospital. Methods: Semi-structured interviews were conducted with patients attending this clinic between October 2022 and January 2023. Data analysis was based on thematic analysis. Results: The themes from interviews with 14 patients (F = 11, M = 3) could be broadly categorized into statements on the pathway to the sOC, and statements on care provided in the sOC. Findings show that patients' high expectations at the sOC appointment were shaped by previous experiences with care, which were mainly perceived as inadequate. Care in the sOC was predominantly perceived as competent, empathetic and relevant for further care and coping with the disease. A deterioration in health directly related to the consultation (classifiable as post-exertional malaise) was frequently described, as was a high need for ongoing consultation. Conclusions: Overall, the findings point to a need for adaptations in the sOC, such as identifying optimized models of care and tailoring them to the patients' limited resources. This includes measures to improve care outside the sOC.

Novel biomarkers of mitochondrial dysfunction in Long COVID patients

Coronavirus disease 2019 (COVID-19) can lead to severe acute respiratory syndrome, and while most individuals recover within weeks, approximately 30-40% experience persistent symptoms collectively known as Long COVID, post-COVID-19 syndrome, or post-acute sequelae of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (PASC). These enduring symptoms, including fatigue, respiratory difficulties, body pain, short-term memory loss, concentration issues, and sleep disturbances, can persist for months. According to recent studies, SARS-CoV-2 infection causes prolonged disruptions in mitochondrial function, significantly altering cellular energy metabolism. Our research employed transmission electron microscopy to reveal distinct mitochondrial structural abnormalities in Long COVID patients, notably including significant swelling, disrupted cristae, and an overall irregular morphology, which collectively indicates severe mitochondrial distress. We noted increased levels of superoxide dismutase 1 which signals oxidative stress and elevated autophagy-related 4B cysteine peptidase levels, indicating disruptions in mitophagy. Importantly, our analysis also identified reduced levels of circulating cell-free mitochondrial DNA (ccf-mtDNA) in these patients, serving as a novel biomarker for the condition. These findings underscore the crucial role of persistent mitochondrial dysfunction in the pathogenesis of Long COVID. Further exploration of the cellular and molecular mechanisms underlying post-viral mitochondrial dysfunction is critical, particularly to understand the roles of autoimmune reactions and the reactivation of latent viruses in perpetuating these conditions. This comprehensive understanding could pave the way for targeted therapeutic interventions designed to alleviate the chronic impacts of Long COVID. By utilizing circulating ccf-mtDNA and other novel mitochondrial biomarkers, we can enhance our diagnostic capabilities and improve the management of this complex syndrome.

Post-COVID-19 Syndrome as Described by Patients: A Qualitative Study

Background/Objectives: Growing interest in post-viral conditions following COVID-19 infection has led researchers and clinicians to develop several definitions of post-COVID-19 syndrome. This study aimed to understand the meaning given to post-COVID-19 syndrome by individuals who survived the first wave of the pandemic two years after its onset. Methods: A descriptive qualitative study was performed according to the Standards for Reporting Qualitative Research guidelines. An inductive and content analysis were adopted on narratives collected via the interview of patients who had been infected with SARS-CoV-2 during the first pandemic wave in the Friuli Venezia Giulia Region (Italy). Results: This study included 230 patients, of whom 158 experienced post-COVID-19 syndrome, and 46 (29.1%) reported suffering from this condition 24 months after the infection. On average, patients experienced three symptoms, with most of them experiencing at least one. Seventy-five patients reported being familiar with the definition of the post-COVID-19 syndrome, mainly through media and the internet (28.9% and 28.2%, respectively). The post-COVID-19 syndrome was described as characterized by two themes: (a) the experience of interrelated physical and psychological symptoms and (b) the experience of fighting like warriors for a long time. Conclusions: The post-COVID-19 syndrome is highly prevalent but poorly understood. Patients rely on low-quality information rather than that offered by clinicians. The post-COVID-19 syndrome appears to be a complex syndrome encompassing physical and mental symptoms, as well as those disabling the person with an unclear trajectory. There is a need to focus on the long-term consequences of COVID-19, incorporating insights from individuals' lived experiences.

An international comparison of longitudinal health data collected on long COVID in nine high income countries: a qualitative data analysis

BACKGROUND

Long coronavirus disease (COVID) presents a significant health challenge. Long-term monitoring is critical to support understanding of the condition, service planning and evaluation. We sought to identify and examine longitudinal health data collected on long COVID to inform potential decisions in England regarding the rationale for data collection, the data collected, the sources from which data were collected and the methods used for collection.

METHODS

We included datasets in high-income countries that experienced similar coronavirus disease 2019 (COVID-19) waves to England pre-vaccine rollout. Relevant datasets were identified through literature searches, the authors' networks and participants' recommendations. We undertook semi-structured interviews with individuals involved in the development and running of the datasets. We held a focus group discussion with representatives of three long COVID patient organisations to capture the perspective of those with long COVID. Emergent findings were tested in a workshop with country interviewees.

RESULTS

We analysed 17 datasets from nine countries (Belgium, Canada, Germany, Italy, the Netherlands, New Zealand, Sweden, Switzerland and the United Kingdom). Datasets sampled different populations, used different data collection tools and measured different outcomes, reflecting different priorities. Most data collection was research (rather than health care system)-funded and time-limited. For datasets linked to specialist services, there was uncertainty surrounding how long these would continue. Definitions of long COVID varied. Patient representatives' favoured self-identification, given challenges in accessing care and receiving a diagnosis; New Zealand's long COVID registry was the only example identified using this approach. Post-exertion malaise, identified by patients as a critical outcome, was absent from all datasets. The lack of patient-reported outcome measures (PROMs) was highlighted as a limitation of datasets reliant on routine health data, although some had developed mechanisms to extend data collection using patient surveys.

CONCLUSIONS

Addressing research questions related to the management of long COVID requires diverse data sources that capture different populations with long COVID over the long-term. No country examined has developed a comprehensive long-term data system for long COVID, and, in many settings, data collection is ending leaving a gap. There is no obvious model for England or other countries to follow, assuming there remains sufficient policy interest in establishing a long-term long COVID patient registry.

Persistent Symptoms and Associated Risk Factors of COVID-19: A Cross-Sectional Study in Minia, Upper Egypt

Background: A significant number of COVID-19 survivors around the world have been reporting persistent symptoms following their recovery. Long COVID is recognized as a condition affecting not only the respiratory but also the gastrointestinal, cardiovascular, neurological, immune, and hematopoietic systems. Objective: This study aimed to describe persistent symptoms in COVID-19 survivors six months post-infection in Minia, Upper Egypt, and investigate associated risk factors. Methods: This observational cross-sectional study included 189 hospitalized and non-hospitalized patients previously diagnosed with COVID-19. Demographic data, symptom severity, comorbidities, and persistent symptoms were collected. A logistic regression analysis was used to identify risk factors associated with long COVID, with statistical significance set at p < 0.05. Results: In total, 68.8% of participants were women, and 83.5% of patients reported at least one ongoing symptom. The most self-reported symptoms were fatigue (73.5%) and myalgia (45.5%), followed by dyspnea (43.3%). Age was associated with an increased risk of developing long COVID (OR 1.028, 95% CI 1.003-1.054, p = 0.030). Patients who were hospitalized during the acute phase had more than twice the risks of having persistent symptoms (OR 2.384, 95% CI 1.055-5.387, p = 0.037). Conclusions: A substantial proportion of COVID-19 survivors in Minia, Upper Egypt, continues to experience persistent symptoms, primarily constitutional and neurological manifestations. Many patients reported self-medicating with unprescribed antibiotics, highlighting a need for public awareness regarding viral infections and the risks associated with improper antibiotic use.

Clinical manifestations of Long-COVID: an observational perspective

Objectives

Coronavirus Disease-19, also known as COVID-19, resulted in a pandemic that caused massive health concerns and economic losses globally. Worldwide, people are still facing persistent clinical symptoms following COVID-19 infection, characterized as Long-COVID. This study aimed to assess the experience and awareness of Long-COVID clinical symptoms in Saudi Arabia.

Methods

This cross-sectional study was conducted at the College of Medicine, Alfaisal University, Riyadh, Saudi Arabia during the period April 5, 2023 to August 30, 2023. An online questionnaire was created using Google Forms and distributed with a URL to students via email and WhatsApp. The questionnaire consisted of 17 questions classifying the respondent's responses. The survey consisted of three sections, addressing demographics, their experience with COVID-19 and whether they had Long-COVID symptoms. A total of 490 participants participated in the study survey. The Statistical Package for Social Sciences (SPSS) version 28 was used for data administration and analysis. P-values <0.05 were considered statistically significant.

Results

Out of the participants, 53.9% had prior exposure to COVID-19. During acute infection, tiredness was the most common symptom in participants, observed in 84.5% of people. The other common symptoms which were reported among the participants included fever (75%), soreness of throat (65.5%), headache (65.2). Some symptoms were more dominant in males (such as acne) and some in females (hair loss). Regarding prolonged symptoms, 43.6% of females and 33.3% of males had experienced symptoms of Long-COVID. Tiredness was once again the most dominant symptom (16.7%). The other common prolonged symptoms of Long-COVID observed were loss of taste or smell (9.1%), body pain (7.6%), headache (7.2%), foggy memory (7.2%) and shortness of breath (6.4%). Lastly, awareness of Long COVID was lower than expected, with 51.5% of females and 55.1% of males unaware of the syndrome.

Conclusion

This study's findings show the effects Long COVID-19 has on the general population, which includes various symptoms affecting physical, mental and emotional needs. The findings also suggest potential gender differences in Long-COVID clinical symptoms, thus highlighting the need for further research with larger and more diverse samples.

Feasibility, acceptance and effects of pulsed magnetic field therapy in patients with post-COVID-19 fatigue syndrome : A randomized controlled pilot study

INTRODUCTION

The aim of this randomized, single-blinded, placebo-controlled pilot study was to explore the feasibility, acceptance and effects of pulsed electromagnetic field therapy (PEMF) in patients with post-COVID-19 fatigue syndrome.

METHODS

A total of 20 patients were included in the study. They were randomly assigned to an intervention group (n = 10, male:female = 4 : 5, age = 45 ± 9 years) and a placebo group (n = 10, m:f = 4:6, age: 39 ± 23 years). A Papimi™ Delta professional electromagnetic field therapy device was used for treatment. Controls received a placebo PEMF. In total 10 PEMF sessions (30 min., 2× per week) were applied. Physical performance, health-related quality of life, fatigue, work ability, sleep, pain, anxiety and depression were assessed at baseline, posttreatment and at follow-up 5 weeks after treatment. Feasibility and acceptance were assessed posttreatment.

RESULTS

The intervention group showed a notable improvement in the 6 minutes walking test. The use of PEMF improved fatigue (measured with the Brief Fatigue Inventory and the Multidimensional Fatigue Inventory). Also, the depression subscale of the Hospital Anxiety and Depression Scale, the Insomnia Severity Index, the Work Ability Index and most subscales of the Short Form (SF) 36 questionnaire showed improvement. From the placebo group three patients dropped out. There were no drop-outs in the intervention group. In the intervention group, PEMF was well-accepted and patients showed very good adherence.

CONCLUSION

The results of this pilot study indicate that PEMF is feasible and well accepted. Furthermore, this study population showed improvements in physical and mental health in the intervention group. This study is a promising contribution to this growing research field and provides the required evidence for future efficacy studies on PEMF for post-COVID-19 patients.

Explainable machine learning model and nomogram for predicting the efficacy of Traditional Chinese Medicine in treating Long COVID: a retrospective study

Introduction

Long COVID significantly affects patients' quality of life, yet no standardized treatment has been established. Traditional Chinese Medicine (TCM) presents a promising potential approach with targeted therapeutic strategies. This study aims to develop an explainable machine learning (ML) model and nomogram to identify Long COVID patients who may benefit from TCM, enhancing clinical decision-making.

Methods

We analyzed data from 1,331 Long COVID patients treated with TCM between December 2022 and February 2024 at three hospitals in Zhejiang, China. Effectiveness was defined as improvement in two or more symptoms or a minimum 2-point increase in the Traditional Chinese Medicine Syndrome Score (TCMSS). Data included 11 patient and disease characteristics, 18 clinical symptoms and syndrome scores, and 12 auxiliary examination indicators. The least absolute shrinkage and selection operator (LASSO) method identified features linked to TCM efficacy. Data from 1,204 patients served as the training set, while 127 patients formed the testing set.

Results

We employed five ML algorithms: Support Vector Machine (SVM), Random Forest (RF), K-Nearest Neighbors (KNN), Extreme Gradient Boosting (XGBoost), and Neural Network (NN). The XGBoost model achieved an Area Under the Curve (AUC) of 0.9957 and an F1 score of 0.9852 in the training set, demonstrating superior performance in the testing set with an AUC of 0.9059 and F1 score of 0.9027. Key features identified through SHapley Additive exPlanations (SHAP) included chest tightness, aversion to cold, age, TCMSS, Short Form (36) Health Survey (SF-36), C-reactive protein (CRP), and lymphocyte ratio. The logistic regression-based nomogram demonstrated an AUC of 0.9479 and F1 score of 0.9384 in the testing set.

Conclusion

This study utilized multicenter data and multiple ML algorithms to create a ML model for predicting TCM efficacy in Long COVID treatment. Furthermore, a logistic regression-based nomogram was developed to assist the model and improve decision-making efficiency in TCM applications for Long COVID management.

The Effect of COVID-19 on Arterial Stiffness and Inflammation: A Longitudinal Prospective Study

Data are limited for assessing the effect of COVID infection on endothelial function, pre- and post-pandemic. The objective of this study was to assess changes in pre-pandemic cardiovascular parameters after COVID-19 infection. This prospective cohort study used EndoPAT2000 Itamar Medical Ltd., Caesarea, Israel, to measure the augmentation index (AI; arterial elasticity) and reactive hyperemic index (RHI; endothelial function). Markers of endothelial function, inflammation, and gut integrity were collected at pre- and post-pandemic visits. COVID-negative and COVID-positive participants were matched on pre-pandemic covariates, and AI ≥ 5.0 was defined as having worse AI. Among the 156 participants, 50% had documented COVID-19 infection. Groups were balanced (p > 0.05) on pre-pandemic characteristics. Increases in oxLDL (p = 0.03) were observed in the COVID-positive group, and COVID infection had a negative effect on inflammatory markers (sVCAM-1, sTNF-RI, sTNF-RII, sCD14) and gut integrity (I-FABP, BDG) compared to COVID-negative participants (p < 0.05). There was a 16.7% (p = 0.02) increase in the proportion of COVID-positive participants with AI ≥ 5.0, without a significant change (p = 0.09) among the COVID-negative group. COVID-positive status, female sex, and higher IL-6 and sCD163 were associated (p < 0.05) with an increase in having worse AI. COVID infection is independently associated with arterial stiffness. For COVID survivors, female sex and higher markers of inflammation were associated with arterial stiffness.

Long-Term Evolution of Post-COVID-19 Echocardiographic Parameters in Patients with Chronic Kidney Disease: A Prospective Comparative Observational Study

Background/Objectives: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has caused post-acute sequelae, especially for people with pre-existing conditions, including chronic kidney disease (CKD), which may impact the cardiovascular system. Yet, despite the preliminary description of the general population's long-COVID-19 consequences, data on CKD patients is scarce. The aim of this study was to investigate the longitudinal effects of COVID-19 on echocardiographic parameters of cardiac function and on cardiac biomarkers in patients with CKD. Methods: A total of 163 patients were included in this observational prospective trial (listed under NCT05125913 code): 88 in the COVID-19 group and 75 in the control group. The serial echocardiographic characteristics in patients who survived beyond one year, focused on left and right ventricular systolic function, together with cardiac biomarkers evolution, were compared between the two groups. Results: At baseline, there were no significant differences in left ventricular (LV) function parameters, except for a higher Tei Index in the COVID-19 group (p < 0.01). Right ventricular (RV) systolic dysfunction was more frequent in the COVID-19 group, with worse fractional area change (FAC) (p = 0.01), RV free wall longitudinal strain (RVFWLS) (p = 0.01), and RV Tei Index (p = 0.01). Over time, the control group showed a decline in LV ejection fraction (EF), while the COVID-19 group slightly improved. RV global systolic function was better preserved in the COVID-19 group. To the best of our knowledge, this is the first study that demonstrates a statistically significant increase in LAVi in patients with COVID-19. Conclusions: Prior COVID-19 infection influenced the trajectory of LV and RV function in CKD patients over 12 months, suggesting potential transient myocardial adaptations. While overall cardiac function did not differ significantly between groups, COVID-19 survivors exhibited better preservation of some ventricular function parameters.

Convalescent COVID-19 monocytes exhibit altered steady-state gene expression and reduced TLR2, TLR4 and RIG-I induced cytokine expression

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes COVID-19, can induce trained immunity in monocytes. Trained immunity is the result of metabolic and epigenetic reprogramming of progenitor cells leading to an altered inflammatory response to subsequent activation. To investigate the monocyte response 3-6 months post SARS-CoV-2 infection, steady-state gene expression and innate immune receptor stimulation were investigated in monocytes from unvaccinated SARS-CoV-2 naïve individuals and convalescent COVID-19 participants. The differentially expressed genes (DEGs) identified were involved in the regulation of innate immune signalling pathways associated with anti-viral defence. COVID-19 participants who had experienced severe symptoms exhibited a larger number of DEGs than participants that had mild symptoms. Interestingly, genes encoding receptors that recognise SARS-CoV-2 RNA were downregulated. DDX58, encoding retinoic-acid inducible gene I (RIG-I), was downregulated which corresponded with a reduced response to RIG-I activation. Furthermore, toll-like receptor (TLR)1/2 and TLR4 activation also exhibited reduced cytokine secretion from convalescent COVID-19 monocytes. These data suggest that following SARS-CoV-2 infection, monocytes exhibit altered steady-state gene expression and reduced responsiveness to innate immune receptor activation. As both RIG-I and TLRs recognise components of SARS-CoV-2, this may lead to a moderated inflammatory response to SARS-CoV-2 reinfection in the months following the initial infection.