Persistent SARS-CoV-2 Infection, EBV, HHV-6 and Other Factors May Contribute to Inflammation and Autoimmunity in Long COVID

Abstract:

A novel syndrome called long-haul COVID or long COVID is increasingly recognized in a significant percentage of individuals within a few months after infection with SARS-CoV-2. This disorder is characterized by a wide range of persisting, returning or even new but related symptoms that involve different tissues and organs, including respiratory, cardiac, vascular, gastrointestinal, musculo-skeletal, neurological, endocrine and systemic.
Some overlapping symptomatologies exist between long COVID and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Very much like with long ME/CFS, infections with herpes family viruses, immune dysregulation, and the persistence of inflammation have been reported as the most common pattern for the development of long COVID.
This review describes several factors and determinants of long COVID that have been proposed, elaborating mainly on viral persistence, reactivation of latent viruses such as Epstein–Barr virus and human herpesvirus 6 which are also associated with the pathology of ME/CFS, viral superantigen activation of the immune system, disturbance in the gut microbiome, and multiple tissue damage and autoimmunity.
Based on these factors, we propose diagnostic strategies such as the measurement of IgG and IgM antibodies against SARS-CoV-2, EBV, HHV-6, viral superantigens, gut microbiota, and biomarkers of autoimmunity to better understand and manage this multi-factorial disorder that continues to affect millions of people in the world.
Source: Vojdani A, Vojdani E, Saidara E, Maes M. Persistent SARS-CoV-2 Infection, EBV, HHV-6 and Other Factors May Contribute to Inflammation and Autoimmunity in Long COVID. Viruses. 2023; 15(2):400. https://doi.org/10.3390/v15020400 https://www.mdpi.com/1999-4915/15/2/400 (Full text)

The direct correlation between microbiota and SARS-CoV-2 infectious disease

Abstract:

The human microbiota is the good part of the human organism and is a collection of symbiotic microorganisms which aid in human physiological functions. Diseases that can be generated by an altered microbiota are continuously being studied, but it is quite evident how a damaged microbiota is involved in chronic inflammatory diseases, psychiatric diseases, and some bacterial or viral infections. However, the role of the microbiota in the host immune response to bacterial and viral infections is still not entirely understood.

Metabolites or components which are produced by the microbiota are useful in mediating microbiota-host interactions, thus influencing the host’s immune capacity. Recent evidence shows that the microbiota is evidently altered in patients with viral infections such as post-acute COVID-19 syndrome (PACS).

In this review, the associations between microbiota and COVID-19 infection are highlighted in terms of biological and clinical significance by emphasizing the mechanisms through which metabolites produced by the microbiota modulate immune responses to COVID-19 infection.

Source: Vitiello A, Ferrara F, Zovi A. The direct correlation between microbiota and SARS-CoV-2 infectious disease. Inflammopharmacology. 2023 Feb 1:1–8. doi: 10.1007/s10787-023-01145-9. Epub ahead of print. PMID: 36725821; PMCID: PMC9891758. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9891758/ (Full text)

Long COVID Syndrome and Cardiovascular Manifestations: A Systematic Review and Meta-Analysis

Abstract:

Background: Long COVID syndrome is a significant cause of morbidity in COVID-19 patients who remain symptomatic with varied clinical presentations beyond three weeks. Furthermore, the relevance of considering cardiovascular outcomes in post-COVID-19 syndrome is important in the current COVID-19 pandemic.
Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed for this systematic review and meta-analysis. Systematic searches were conducted from multiple databases without language restrictions until October 8, 2022, to find studies evaluating cardiovascular outcomes such as arrhythmias, myocardium and pericardium diseases, coronary vessel disease, and thromboembolic disorders in post-COVID cases. The pooled odds ratio (OR), and standard mean difference (SMD) with their corresponding 95% confidence intervals (CI) were computed to find the association.
Results: Altogether, seven studies with a total of 8,126,462 (cases: 1,321,305; controls: 6,805,157) participants were included in the meta-analysis. Pooled odds ratios of cardiovascular outcomes were significantly higher in post-COVID cases (OR > 1, p < 0.05) than in controls. However, the mortality (OR: 4.76, p = 0.13), and heart rate variability (SMD: −0.06, p = 0.91) between cases and controls were not statistically significant.
Conclusions: Significant cardiovascular sequelae in long COVID syndrome highlight the importance of careful cardiac monitoring of COVID-19 patients in the post-COVID phase to address cardiovascular complications as soon as possible; larger-scale prospective studies are required for accurate estimation.
Source: Shrestha AB, Mehta A, Pokharel P, Mishra A, Adhikari L, Shrestha S, Yadav RS, Khanal S, Sah R, Nowrouzi-Kia B, Padhi BK, Chattu VK. Long COVID Syndrome and Cardiovascular Manifestations: A Systematic Review and Meta-Analysis. Diagnostics. 2023; 13(3):491. https://doi.org/10.3390/diagnostics13030491 https://www.mdpi.com/2075-4418/13/3/491 (Full text)

Functional Neurological Disorder in people with Long-Covid: A Systematic Review

Abstract:

Background: Acute health events, including infections, can trigger the onset of functional neurological disorder (FND). We hypothesised that a proportion of people with long-COVID might be experiencing functional symptoms.

Methods: We performed a systematic review of studies containing original data on long-COVID. We reviewed the frequency and characteristics of neurological symptoms, looking for positive evidence suggesting an underlying functional disorder, and the hypothesised causes of long-COVID.

Results: We included 102 studies in our narrative synthesis. The most consistently reported neurological symptoms were cognitive difficulties, headaches, pain, dizziness, fatigue, sleep-related symptoms, and ageusia/anosmia. Overall, we found no evidence that any authors had systematically looked for positive features of FND. An exception were three studies describing temporal inconsistency. In general, the neurological symptoms were insufficiently characterised in order to support or refute a diagnosis of FND. Moreover, only 13 studies specifically focussed on long-COVID after mild infection, where the impact of confounders from the general effects of severe illness would be mitigated. Only one study hypothesised that some people with long-COVID might have a functional disorder, and another 8 studies a chronic fatigue syndrome-like response.

Discussion: Neurological symptoms are prevalent in long-COVID, but poorly characterised. We are struck by the similarities between some manifestations of long-COVID and functional disorders triggered by acute illnesses. Unfortunately, the current literature is plagued by confounders, including the mixing of patients with initial mild infection with those with severe acute medical complications. The hypothesis that long-COVID might in part correspond to a functional disorder remains untested.

Source: Teodoro T, Chen J, Gelauff J, Edwards MJ. Functional Neurological Disorder in people with Long-Covid: A Systematic Review. Eur J Neurol. 2023 Jan 31. doi: 10.1111/ene.15721. Epub ahead of print. PMID: 36719069. https://onlinelibrary.wiley.com/doi/10.1111/ene.15721 (Full text available as PDF file)

Inflammatory and vascular biomarkers in post-COVID-19 syndrome: A systematic review and meta-analysis of over 20 biomarkers

Abstract:

Severe acute respiratory syndrome coronavirus 2 may inflict a post-viral condition known as post-COVID-19 syndrome (PCS) or long-COVID. Studies measuring levels of inflammatory and vascular biomarkers in blood, serum, or plasma of COVID-19 survivors with PCS versus non-PCS controls have produced mixed findings. Our review sought to meta-analyse those studies. A systematic literature search was performed across five databases until 25 June 2022, with an updated search on 1 November 2022.

Data analyses were performed with Review Manager and R Studio statistical software. Twenty-four biomarkers from 23 studies were meta-analysed. Higher levels of C-reactive protein (Standardized mean difference (SMD) = 0.20; 95% CI: 0.02-0.39), D-dimer (SMD = 0.27; 95% CI: 0.09-0.46), lactate dehydrogenase (SMD = 0.30; 95% CI: 0.05-0.54), and leukocytes (SMD = 0.34; 95% CI: 0.02-0.66) were found in COVID-19 survivors with PCS than in those without PCS. After sensitivity analyses, lymphocytes (SMD = 0.30; 95% CI: 0.12-0.48) and interleukin-6 (SMD = 0.30; 95% CI: 0.12-0.49) were also significantly higher in PCS than non-PCS cases. No significant differences were noted in the remaining biomarkers investigated (e.g., ferritin, platelets, troponin, and fibrinogen). Subgroup analyses suggested the biomarker changes were mainly driven by PCS cases diagnosed via manifestation of organ abnormalities rather than symptomatic persistence, as well as PCS cases with duration of <6 than ≥6 months.

In conclusion, our review pinpointed certain inflammatory and vascular biomarkers associated with PCS, which may shed light on potential new approaches to understanding, diagnosing, and treating PCS.

Source: Yong SJ, Halim A, Halim M, Liu S, Aljeldah M, Al Shammari BR, Alwarthan S, Alhajri M, Alawfi A, Alshengeti A, Khamis F, Alsalman J, Alshukairi AN, Abukhamis NA, Almaghrabi FS, Almuthree SA, Alsulaiman AM, Alshehail BM, Alfaraj AH, Alhawaj SA, Mohapatra RK, Rabaan AA. Inflammatory and vascular biomarkers in post-COVID-19 syndrome: A systematic review and meta-analysis of over 20 biomarkers. Rev Med Virol. 2023 Jan 27:e2424. doi: 10.1002/rmv.2424. Epub ahead of print. PMID: 36708022. https://pubmed.ncbi.nlm.nih.gov/36708022/ 

Mechanisms, Effects, and Management of Neurological Complications of Post-Acute Sequelae of COVID-19 (NC-PASC)

Abstract:

With a growing number of patients entering the recovery phase following infection with SARS-CoV-2, understanding the long-term neurological consequences of the disease is important to their care. The neurological complications of post-acute sequelae of SARS-CoV-2 infection (NC-PASC) represent a myriad of symptoms including headaches, brain fog, numbness/tingling, and other neurological symptoms that many people report long after their acute infection has resolved.
Emerging reports are being published concerning COVID-19 and its chronic effects, yet limited knowledge of disease mechanisms has challenged therapeutic efforts. To address these issues, we review broadly the literature spanning 2020–2022 concerning the proposed mechanisms underlying NC-PASC, outline the long-term neurological sequelae associated with COVID-19, and discuss potential clinical interventions.
Source: Ong IZ, Kolson DL, Schindler MK. Mechanisms, Effects, and Management of Neurological Complications of Post-Acute Sequelae of COVID-19 (NC-PASC). Biomedicines. 2023; 11(2):377. https://doi.org/10.3390/biomedicines11020377 https://www.mdpi.com/2227-9059/11/2/377

What interventions or best practice are there to support people with Long COVID, or similar post-viral conditions or conditions characterised by fatigue, to return to normal activities: a rapid review

Abstract:

Previous research has categorised symptoms of COVID-19 / Long COVID into 12 thematic areas including: fever, myalgia, fatigue, impaired cognitive function, and that COVID-19 survivors had reduced levels of physical function, activities of daily living, and health-related quality of life.

Our aim was to review the evidence for interventions or best practice to support people with Long COVID, or similar post-viral conditions characterised by fatigue, to return to normal activities.

Evidence was included from guidelines, systematic reviews (SR), and primary studies. The primary studies focussed on Long COVID (LC) indicated that there should be a needs-based focus to care for those with LC.

Consideration should be given to individuals living with LC in the same way as people with disabilities are accommodated in terms of workplace adjustment.

Two SRs indicated that non-pharmaceutical interventions (NPIs) for patients with LC or chronic fatigue syndrome could help improve function for activities of daily life. However, the third, most recent SR, concluded that there is a lack of robust evidence for NPIs.

LC fatigue management methods may be beneficial under certain conditions. One SR reported work capability as an outcome however they did not find any studies which evaluated the impact of interventions on return to work/ normal life.

One primary study, on individuals with CFS, described a written self-management programme. Following this intervention there was an 18% increase in the number of patients in employment.

Policy and practice implications: Long COVID is still being established as a post-viral condition with many symptoms. Patient-centred treatment options such as occupational therapy, self-management therapy and talking therapy may be considered in the same way as for other debilitating conditions. Return-to-work accommodations are needed for all workers unable to return to full-time employment.

Due to the nature of the studies included, there was little reported evidence of effectiveness of getting individuals back into their normal activities.

Source: Llinos Haf Spencer, Annie Hendry, Abraham Makanjuola, Bethany F Anthony, Jacob Davies, Kalpa Pisavadia, Dyfrig Hughes, Deb Fitzsimmons, Clare Wilkinson, Rhiannon Tudor Edwards, Ruth Lewis, Alison Cooper, Adrian Edwards. What interventions or best practice are there to support people with Long COVID, or similar post-viral conditions or conditions characterised by fatigue, to return to normal activities: a rapid review. medRxiv 2023.01.24.23284947; doi: https://doi.org/10.1101/2023.01.24.23284947 (Full text)

Long COVID: Is There a Role for Antidepressants?

Abstract:

Two years into this historic pandemic, the scientific and healthcare communities continue to learn a great deal regarding COVID-19. The most urgent and immediate focus has been on vaccine development for disease prevention/mitigation and on identification of effective therapeutic interventions for acute phase of illness. However, attention is increasingly being placed on formulating treatment strategies for individuals who are post-COVID-19 and experiencing a syndrome of persistent symptoms that is being referred to as long COVID.

One strategy is to repurpose drugs which have been approved for other conditions and subsequently assess their safety and efficacy when applied to COVID-19. In this light, antidepressant medications have garnered attention amidst evidence supporting anti-inflammatory and anti-viral properties.

In this article, we present purported anti-inflammatory mechanisms of antidepressants, review studies appearing in the literature to date regarding antidepressants and acute COVID-19, and discuss the utility of antidepressants as a potential therapeutic resource for long COVID.

Source: Rivas-Vázquez R, Carrazana EJ, Blais MA, Rey GJ, RivasVázquez E, Quintana AA. Long COVID: Is There a Role for Antidepressants? Neurol Curr Res. 2022;2(3):1019. https://www.medtextpublications.com/open-access/long-covid-is-there-a-role-for-antidepressants-1249.pdf (Full text)

Towards evidence-based and inclusive models of peer support for long covid: A hermeneutic systematic review

Highlights:

• Co-produced peer support can help people living with Long COVID.
• Increasing the use of effective peer support may reduce health inequalities.
• Inclusive peer support can benefit ‘hardly reached’ Long Covid cohorts.
• Linking biomedical, relational and socio-political styles are most effective.

Abstract:

Since the first wave of COVID-19 in March 2020 the number of people living with post-COVID syndrome has risen rapidly at global pace, however, questions still remain as to whether there is a hidden cohort of sufferers not accessing mainstream clinics. This group are likely to be constituted by already marginalised people at the sharp end of existing health inequalities and not accessing formal clinics. The challenge of supporting such patients includes the question of how best to organise and facilitate different forms of support.

As such, we aim to examine whether peer support is a potential option for hidden or hardly reached populations of long COVID sufferers with a specific focus on the UK, though not exclusively. Through a systematic hermeneutic literature review of peer support in other conditions (57 papers), we evaluate the global potential of peer support for the ongoing needs of people living with long COVID.

Through our analysis, we highlight three key peer support perspectives in healthcare reflecting particular theoretical perspectives, goals, and understandings of what is ‘good health’, we call these: biomedical (disease control/management), relational (intersubjective mutual support) and socio-political (advocacy, campaigning & social context). Additionally, we identify three broad models for delivering peer support: service-ledcommunity-based and social media. Attention to power relations, social and cultural capital, and a co-design approach are key when developing peer support services for disadvantaged and underserved groups.

Models from other long-term conditions suggest that peer support for long COVID can and should go beyond biomedical goals and harness the power of relational support and collective advocacy. This may be particularly important when seeking to reduce health inequalities and improve access for a potentially hidden cohort of sufferers.

Source: Mullard JCR, Kawalek J, Parkin A, Rayner C, Mir G, Sivan M, Greenhalgh T. Towards evidence-based and inclusive models of peer support for long covid: A hermeneutic systematic review. Soc Sci Med. 2023 Jan 14:115669. doi: 10.1016/j.socscimed.2023.115669. Epub ahead of print. PMCID: PMC9840228. https://www.sciencedirect.com/science/article/pii/S0277953623000242 (Full text)

A Systematic Review of Trials Currently Investigating Therapeutic Modalities for Post-Acute COVID-19 Syndrome and Registered on World Health Organization International Clinical Trials Platform

Abstract:

Background: Post-acute coronavirus 2019 (COVID-19) syndrome (PACS) is a well-recognized complex systemic disease that is associated with substantial morbidity. There is a paucity of established interventions to treat patients with this syndrome.

Objectives: To systematically review registered trials currently investigating therapeutic modalities for PACS.

Data sources: Search was conducted up to the 16th of September 2022 using the COVID-19 section of the World Health Organization (WHO) Internal Clinical Trials Registry Platform.

Study eligibility criteria, participants, and interventions: Interventional clinical trials of any sample size examining any therapeutic modality targeting persistent symptoms among individuals after diagnosis with COVID-19.

Methods: Data on trial characteristics and intervention characteristics were collected and summarized.

Results: After screening 17125 trials, 388 trials from 42 countries were eligible. 331 trials tested mono-therapeutic strategies, while 39 trials included a combination of interventions. Among the 824 primary outcomes identified, there were more than 300 different outcomes. Rehabilitation was the most employed class of intervention with 169 trials. We encountered 76 trials examining pharmacological agents of various classes with the most common agent being colchicine. Complementary and alternative medicine encompassed 64 trials exploring Traditional Chinese Medicine, Ayurveda, homeopathic medications, naturopathic medications, vitamins, dietary supplements, and botanicals. Psychotherapeutic and educational interventions were also employed with 12 and 4 trials, respectively. Other interventions including transcranial current direct stimulation, transcutaneous auricular vagus nerve stimulation, general electrical stimulation, cranial electrotherapy stimulation, various stem cell interventions, and oxygen therapy interventions were also employed.

Conclusion: We identified 388 registered trials with a high degree of heterogeneity exploring 144 unique interventions for PACS. Most target general alleviation of symptoms. There is a need for further high-quality and methodologically robust PACS treatment trials conducted with standardization of outcomes while following WHO’s recommendation for uniform evaluation and treatment.

Source: Fawzy NA, Shaar BA, Taha R, Arabi TZ, Sabbah BN, Alkodaymi MS, Omrani OA, Makhzoum T, Almahfoudh NE, Al-Hammad QA, Hejazi W, Obeidat Y, Osman N, Al-Kattan KM, Berbari EF, Tleyjeh IM. A Systematic Review of Trials Currently Investigating Therapeutic Modalities for Post-Acute COVID-19 Syndrome and Registered on World Health Organization International Clinical Trials Platform. Clin Microbiol Infect. 2023 Jan 12:S1198-743X(23)00009-5. doi: 10.1016/j.cmi.2023.01.007. Epub ahead of print. PMID: 36642173; PMCID: PMC9837206. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9837206/ (Full text)