Category: Viruses

Salivary DNA Loads for Human Herpesviruses 6 and 7 Are Correlated With Disease Phenotype in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Abstract:

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a complex chronic condition affecting multiple body systems, with unknown cause, unclear pathogenesis mechanisms, and fluctuating symptoms which may lead to severe debilitation. It is frequently reported to have been triggered by an infection, but there are no clear differences in exposure to, or seroprevalence of, any particular viruses between people with ME/CFS and healthy individuals. However, herpes viruses have been repeatedly hypothesized to underlie the chronic relapsing/remitting form of MS/CFS due to their persistence in a latent form with periodic reactivation. It is possible that ME/CFS is associated with herpes virus reactivation, which has not been detectable previously due to insufficiently sensitive testing methods.

Saliva samples were collected from 30 people living with ME/CFS at monthly intervals for 6 months and at times when they experienced symptom exacerbation, as well as from 14 healthy control individuals. The viral DNA load of the nine humanherpes viruses was determined by digital droplet PCR. Symptoms were assessed by questionnaire at each time point. Human herpesvirus (HHV) 6B, HHV-7, herpes simplex virus 1 and Epstein-Barr virus were detectable within the saliva samples, with higher HHV-6B and HHV-7 viral loads detected in people with ME/CFS than in healthy controls.

Participants with ME/CFS could be broadly separated into two groups: one group displayed fluctuating patterns of herpesviruses detectable across the 6 months while the second group displayed more stable viral presentation. In the first group, there was positive correlation between HHV-6B and HHV-7 viral load and severity of symptom scores, including pain, neurocognition, and autonomic dysfunction.

The results indicate that fluctuating viral DNA load correlates with ME/CFS symptoms: this is in accordance with the hypothesis that pathogenesis is related to herpesvirus reactivation state, and this should be formally tested. Herpesvirus reactivation might be a cause or consequence of dysregulated immune function seen in ME/CFS. The sampling strategy and molecular tools developed here permit such large-scale epidemiological investigations.

Source: Lee JS, Lacerda EM, Nacul L, Kingdon CC, Norris J, O’Boyle S, Roberts CH, Palla L, Riley EM, Cliff JM. Salivary DNA Loads for Human Herpesviruses 6 and 7 Are Correlated With Disease Phenotype in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Front Med (Lausanne). 2021 Aug 6;8:656692. doi: 10.3389/fmed.2021.656692. PMID: 34422848; PMCID: PMC8378328. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8378328/  (Full text)

Human herpesvirus 6 infection and risk of Chronic fatigue syndrome: a systematic review and meta-analysis

Abstract:

Introduction: Chronic fatigue syndrome (CFS) is a neurological disease that is accompanied by excessive fatigue or tiredness. There are several reports confirming the association between human herpesvirus 6 (HHV-6) infection and CFS illness. This systematic review and meta-analysis was performed to integrate the information of published studies with regard to this association until May 2021.

Methods: The literature search was based on keywords including “chronic fatigue syndrome and HHV 6,” “chronic fatigue syndrome and HHV-6,” “chronic fatigue syndrome and HHV6,” “chronic fatigue syndrome and Herpes virus 6,” and “chronic fatigue syndrome and Herpesvirus6” in MEDLINE (PubMed), Web of Science, and EMBASE.

Results: The literature search identified 17 studies to be included in the systematic review and 11 studies in meta-analysis. The symmetry funnel plot and Egger’s test (p value = 0.2) identified no publication bias among studies. Moreover, the low level of I2 revealed homogeneity across studies.

Discussion: In conclusion, the association between the HHV-6 infection and CFS incidence was substantiated. However, the results of this study also suggest that further comprehensive studies are needed to solidify the association between HHV-6 and CFS. Future studies should consider additional factors that may have affected the significance of such a correlation.

Source: Sayed-Hamidreza Mozhgani, Farid Rajabi, Mohsen Qurbani, Yousef Erfani, Somayeh Yaslianifard, Azam Moosavi, Kiomars Pourrostami, Ali Baradaran Bagheri, Alireza Soleimani, Farida Behzadian, Mahshid Safavi, Farhad Rezaei. Human herpesvirus 6 infection and risk of Chronic fatigue syndrome: a systematic review and meta-analysis. Intervirology (IF1.763), Pub Date : 2021-06-23, DOI: 10.1159/000517930 https://www.karger.com/Article/Abstract/517930 (Full text as PDF file)

The Enterovirus Theory of Disease Etiology in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Critical Review

Abstract:

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a complex, multi-system disease whose etiological basis has not been established. Enteroviruses (EVs) as a cause of ME/CFS have sometimes been proposed, as they are known agents of acute respiratory and gastrointestinal infections that may persist in secondary infection sites, including the central nervous system, muscle, and heart. To date, the body of research that has investigated enterovirus infections in relation to ME/CFS supports an increased prevalence of chronic or persistent enteroviral infections in ME/CFS patient cohorts than in healthy individuals. Nevertheless, inconsistent results have fueled a decline in related studies over the past two decades.

This review covers the aspects of ME/CFS pathophysiology that are consistent with a chronic enterovirus infection and critically reviews methodologies and approaches used in past EV-related ME/CFS studies. We describe the prior sample types that were interrogated, the methods used and the limitations to the approaches that were chosen. We conclude that there is considerable evidence that prior outbreaks of ME/CFS were caused by one or more enterovirus groups. Furthermore, we find that the methods used in prior studies were inadequate to rule out the presence of chronic enteroviral infections in individuals with ME/CFS. Given the possibility that such infections could be contributing to morbidity and preventing recovery, further studies of appropriate biological samples with the latest molecular methods are urgently needed.

Source: O’Neal AJ, Hanson MR. The Enterovirus Theory of Disease Etiology in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Critical Review. Front Med (Lausanne). 2021 Jun 18;8:688486. doi: 10.3389/fmed.2021.688486. PMID: 34222292; PMCID: PMC8253308. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8253308/  (Full text)

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: The Human Herpesviruses Are Back!

Abstract:

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) or Systemic Exertion Intolerance Disease (SEID) is a chronic multisystem illness of unconfirmed etiology. There are currently no biomarkers and/or signatures available to assist in the diagnosis of the syndrome and while numerous mechanisms have been hypothesized to explain the pathology of ME/CFS, the triggers and/or drivers remain unknown. Initial studies suggested a potential role of the human herpesviruses especially Epstein-Barr virus (EBV) in the disease process but inconsistent and conflicting data led to the erroneous suggestion that these viruses had no role in the syndrome. New studies using more advanced approaches have now demonstrated that specific proteins encoded by EBV could contribute to the immune and neurological abnormalities exhibited by a subgroup of patients with ME/CFS. Elucidating the role of these herpesvirus proteins in ME/CFS may lead to the identification of specific biomarkers and the development of novel therapeutics.

Source: Ariza ME. Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: The Human Herpesviruses Are Back! Biomolecules. 2021 Jan 29;11(2):185. doi: 10.3390/biom11020185. PMID: 33572802. https://www.mdpi.com/2218-273X/11/2/185 (Full text)

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

Abstract:

As the SARS-COV-2 becomes a global pandemic, many researchers have a concern about the long COVID-19 complications. Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) is a persistent, debilitating, and unexplained fatigue disorder. We investigated psychological morbidities such as CFS and post-traumatic stress disorder (PTSD) among survivors of COVID-19 over 6 months.

All COVID-19 survivors from the university-affiliated hospital of Tehran, Iran, were assessed 6 months after infection onset by a previously validated questionnaire based on the Fukuda guidelines for CFS/EM and DSM-5 Checklist for PTSD (The Post-traumatic Stress Disorder Checklist for DSM-5 or PCL-5) to determine the presence of stress disorder and chronic fatigue problems. A total of 120 patients were enrolled. The prevalence rate of fatigue symptoms was 17.5%. Twelve (10%) screened positive for chronic idiopathic fatigue (CIF), 6 (5%) for CFS-like with insufficient fatigue syndrome (CFSWIFS), and 3 (2.5%) for CFS. The mean total scores in PCL-5 were 9.27 ± 10.76 (range:0-44), and the prevalence rate of PTSD was 5.8%. There was no significant association after adjusting between CFS and PTSD, gender, comorbidities, and chloroquine phosphate administration.

The obtained data revealed the prevalence of CFS among patients with COVID-19, which is almost similar to CFS prevalence in the general population. Moreover, PTSD in patients with COVID-19 is not associated with the increased risk of CFS. Our study suggested that medical institutions should pay attention to the psychological consequences of the COVID-19 outbreak.

Source: Simani L, Ramezani M, Darazam IA, Sagharichi M, Aalipour MA, Ghorbani F, Pakdaman H. Prevalence and correlates of chronic fatigue syndrome and post-traumatic stress disorder after the outbreak of the COVID-19. J Neurovirol. 2021 Feb 2:1–6. doi: 10.1007/s13365-021-00949-1. Epub ahead of print. PMID: 33528827; PMCID: PMC7852482.  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7852482/ (Full text)

Salivary DNA loads for human herpes viruses 6 and 7 are correlated with disease phenotype in Myalgic Encephalomyelitis/ Chronic Fatigue Syndrome

Abstract:

Myalgic Encephalomyelitis/ Chronic Fatigue Syndrome (ME/CFS) is a complex chronic condition affecting multiple body systems, with unknown cause, unclear pathogenesis mechanisms, and fluctuating symptoms which may lead to severe debilitation. It is frequently reported to have been triggered by an infection, particularly with herpes virus family members; however, there are no clear differences in exposure to, or seroprevalence of, any herpes virus in people with ME/CFS and healthy individuals. Herpes viruses exist in lytic and latent forms, and it is possible that ME/CFS is associated with viral reactivation, which has not been detectable previously due to insensitive testing methods.

Saliva samples were collected from 30 people living with ME/CFS at monthly intervals for six months and at times when they experienced symptom exacerbation, as well as from 14 healthy control individuals. The viral DNA load of the nine human herpes viruses was determined by digital droplet PCR. Symptoms were assessed by questionnaire at each time point.

Human herpes virus (HHV) 6B, HHV-7, herpes simplex virus 1 and Epstein Barr virus were detectable within the saliva samples, with higher HHV-6B and HHV-7 viral loads detected in people with ME/CFS than in healthy controls. Participants with ME/CFS could be broadly separated into two groups: one group displayed fluctuating patterns of herpes viruses detectable across the six months while the second group displayed more stable viral presentation. In the first group, there was positive correlation between HHV-6B and HHV-7 viral load and severity of symptom scores, including pain, neurocognition and autonomic dysfunction.

The results indicate that fluctuating viral load, related to herpesvirus reactivation state, may play a role in ME/CFS pathogenesis, or might be a consequence of dysregulated immune function. The sampling strategy and molecular tools developed permit large-scale epidemiological investigations.

Contribution to the Field The cause of ME/CFS and the mechanisms underlying disease pathogenesis are not known, although symptoms are often triggered by infection. Human herpes virus (HHV) family members have been implicated, although there is no difference in the seroprevalence of any HHV in people with ME/CFS and healthy controls, showing there is similar prior infection rate. HHVs exist in either latent or active, lytic, phases in the human host, and it is possible that ME/CFS symptoms and their severity is related to HHV reactivation from a latent state. We have used droplet digital PCR, a sensitive and specific method, to measure the prevalence and DNA concentration of HHVs in the saliva of people with ME/CFS and controls, and analysed the correlation with disease over a six-month timecourse. We found that two HHVs, HHV-7 and HHV-6B, were elevated in saliva from people with ME/CFS, and that in people who were severely affected by ME/CFS, the concentration HHV DNA correlated with symptom severity over time in a subgroup of patients with fluctuating salivary HHV repertoire. Our study demonstrates the feasibility of measuring HHV concentration in readily acquired samples, enabling future large-scale studies aimed at testing the causal role of HHV reactivation in ME/CFS disease.

Source: Ji-Sook Lee, Eliana M. Lacerda, Luis Nacul, Caroline C. Kingdon, Jasmin Norris, Shennae O’Boyle, Chrissy H. Roberts, Luigi Palla, Eleanor M. Riley, Jacqueline M. Cliff. Salivary DNA loads for human herpes viruses 6 and 7 are correlated with disease phenotype in Myalgic Encephalomyelitis/ Chronic Fatigue Syndrome.
medRxiv 2021.01.06.20248486; doi: https://doi.org/10.1101/2021.01.06.20248486 https://www.medrxiv.org/content/10.1101/2021.01.06.20248486v1.full-text  (Full text)

Will COVID-19 Lead to ME/CFS?

INTRODUCTION:

“Recovering” from COVID-19 does not guarantee a return to a person’s usual state of health. For one thing, some people with multi-system injury—particularly to the brain, heart and kidneys—may develop permanent dysfunction of those organs.
In addition, a more subtle form of chronic illness may develop. For some people with COVID-19, even those who are mildly affected at first, the ensuing weeks and months of “recovery” bring a surprise and a betrayal: they do not return to full health. Although nucleic acid tests no longer detect the virus, people still suffer from ongoing symptoms. They call themselves “long haulers”, and the condition is being called “long COVID”.

Source: Anthony L. Komaroff and Lucinda Bateman. Will COVID-19 Lead to ME/CFS? Front. Med. | doi: 10.3389/fmed.2020.606824 https://www.frontiersin.org/articles/10.3389/fmed.2020.606824/full (Full text)

Commentary: Antibodies to Human Herpesviruses in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients

Introduction: Studies to ascertain a possible relationship between herpesviruses and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) have relied heavily on classical approaches, specifically, serological examination for antibodies against virus proteins, primarily structural, and/or increases in viral load (1–21). These data have been conflicting due in part to several features: the heterogeneity of the disease, high prevalence of the herpesviruses in the population since they can establish lifelong infections, and differences between laboratories. Two additional problems lead to conflicting data in serological studies: which viral antigens are to be used for detection, and what is the possible relationship, if any, of these viral antigens to ME/CFS? These are important questions that must be addressed for any data to provide meaningful insight into the possible contribution of a virus to the pathophysiology of ME/CFS. Although the experimental techniques used in Blomberg’s serological study were appropriate, the selection of specific herpesviruses and viral antigens studied gives a limited view of the humoral response in ME/CFS.

Discussion: Blomberg et al. (22) used a suspension multiplex immunoassay to detect antibodies against various herpesviruses’ antigens, derived from proteins expressed during latency or late lytic replication (Figure 1), with the goal of determining differences in antibody titers against these antigens between ME/CFS patients and controls. However, no rationale was given as to why these particular antigens were chosen and what association, if any, they may have with ME/CFS. This is important because the antigenic properties of the different virus proteins are not the same. As demonstrated in an eloquent study by Vaider-Shalt et al. (23), over the course of their evolution, herpes simplex virus 1 (HSV-1), Epstein-Barr virus (EBV), human herpesvirus 8 (HHV-8), and human cytomegalovirus have decreased the number of epitopes present in virus proteins in order to help them avoid immune detection. Thus, the ability of a virus protein to generate an antibody response is dependent upon the amount of protein present in the host and its antigenicity. It is also not clear why Blomberg et al. (22) included HSV-1/2, human cytomegalovirus, HHV-7, and varicella zoster virus (VZV) in their study since there are no up-to-date literature reports establishing a serological relationship between these viruses and ME/CFS.

Source: Ariza ME. Commentary: Antibodies to Human Herpesviruses in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients. Front Immunol. 2020;11:1400. Published 2020 Jul 23. doi:10.3389/fimmu.2020.01400 https://www.frontiersin.org/articles/10.3389/fimmu.2020.01400/full (Full text)

Post-viral fatigue and COVID-19: lessons from past epidemics

Abstract:

The COVID-19 pandemic, resulting from Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), has severely impacted the population worldwide with a great mortality rate. The current article reviews the literature on short- and long-term health consequences of prior epidemics and infections to assess potential health complications that may be associated with post-COVID-19 recovery. Past research on post-epidemic and post-infection recovery has suggested that such complications include the development of severe fatigue.

Certain factors, such as the severity of infection, in addition to the ‘cytokine storm’ experienced by many COVID-19 patients, may contribute to the development of later health problems. We suggest that the patterns observed in past epidemics and infections may re-occur in the current COVID-19 pandemic.

Source: Mohammed F. Islam, Joseph Cotler & Leonard A. Jason (2020) Post-viral fatigue and COVID-19: lessons from past epidemics, Fatigue: Biomedicine, Health & Behavior, DOI: 10.1080/21641846.2020.1778227 https://www.tandfonline.com/doi/full/10.1080/21641846.2020.1778227 (Full article)

Human Herpesvirus-6 Reactivation, Mitochondrial Fragmentation, and the Coordination of Antiviral and Metabolic Phenotypes in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a multifactorial disorder with many possible triggers. Human herpesvirus (HHV)–6 and HHV-7 are two infectious triggers for which evidence has been growing. To understand possible causative role of HHV-6 in ME/CFS, metabolic and antiviral phenotypes of U2-OS cells were studied with and without chromosomally integrated HHV-6 and with or without virus reactivation using the histone deacetylase inhibitor trichostatin-A. Proteomic analysis was conducted by pulsed stable isotope labeling by amino acids in cell culture analysis.

Antiviral properties that were induced by HHV-6 transactivation were studied in virus-naive A549 cells challenged by infection with influenza-A (H1N1) or HSV-1. Mitochondria were fragmented and 1-carbon metabolism, dUTPase, and thymidylate synthase were strongly induced by HHV-6 reactivation, whereas superoxide dismutase 2 and proteins required for mitochondrial oxidation of fatty acid, amino acid, and glucose metabolism, including pyruvate dehydrogenase, were strongly inhibited. Adoptive transfer of U2-OS cell supernatants after reactivation of HHV-6A led to an antiviral state in A549 cells that prevented superinfection with influenza-A and HSV-1. Adoptive transfer of serum from 10 patients with ME/CFS produced a similar fragmentation of mitochondria and the associated antiviral state in the A549 cell assay.

In conclusion, HHV-6 reactivation in ME/CFS patients activates a multisystem, proinflammatory, cell danger response that protects against certain RNA and DNA virus infections but comes at the cost of mitochondrial fragmentation and severely compromised energy metabolism.

Source: Philipp Schreiner, Thomas Harrer, Carmen Scheibenbogen, Stephanie Lamer, Andreas Schlosser, Robert K. Naviaux and Bhupesh K. Prusty. Human Herpesvirus-6 Reactivation, Mitochondrial Fragmentation, and the Coordination of Antiviral and Metabolic Phenotypes in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. ImmunoHorizons April 1, 2020, 4 (4) 201-215; DOI: https://doi.org/10.4049/immunohorizons.2000006 https://www.immunohorizons.org/content/4/4/201  (Full text)