Post-COVID sequalae effect in chronic fatigue syndrome: SARS-CoV-2 triggers latent adenovirus in the oral mucosa

Abstract:

The post-viral fatigue syndromes long COVID and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) have multiple, potentially overlapping, pathological processes. These include persisting reservoirs of virus e.g. SARS-CoV-2 in long COVID patient’s tissues, immune dysregulation with or without reactivation of underlying pathogens, such as Epstein-Barr virus (EBV) and human herpesvirus 6 (HHV6), as we recently described in ME/CFS, and possibly yet unidentified viruses.

In the present study we tested saliva samples from two cohorts for IgG against human adenovirus (HAdV): patients with ME/CFS (n=84) and healthy controls (n=94), with either mild/asymptomatic SARS-CoV-2 infection or no infection. A significantly elevated anti-HAdV IgG response after SARS-CoV-2 infection was detected exclusively in the patient cohort. Longitudinal/time analysis, before and after COVID-19, in the very same individuals confirmed HAdV IgG elevation after. In plasma there was no HAdV IgG elevation.

We conclude that COVID-19 triggered reactivation of dormant HAdV in the oral mucosa of chronic fatigue patients indicating an exhausted dysfunctional antiviral immune response in ME/CFS, allowing reactivation of adenovirus upon stress encounter such as COVID-19.

Source: Ulf Hannestad, Eirini Apostolou, Per Sjogren, Björn Bragée, Olli Polo, Bo C. Bertilson and Anders Rosén. Post-COVID sequalae effect in chronic fatigue syndrome: SARS-CoV-2 triggers latent adenovirus in the oral mucosa. Front. Med. Sec. Infectious Diseases: Pathogenesis and Therapy, Volume 10 – 2023 | doi: 10.3389/fmed.2023.1208181 https://www.frontiersin.org/articles/10.3389/fmed.2023.1208181/abstract

Viral infection and its causative role for chronic fatigue syndrome

Abstract:

Patients with chronic fatigue syndrome (CFS), of unknown etiology, have been increasingly reported. This syndrome is characterized by debilitating fatigue, lymphadenopathy, and fever. Herein, I focus on and review this syndrome from the view point of the causative role of viral infection. Since the symptoms of CFS are similar to those of chronic infectious mononucleosis (CIM) or chronic Epstein-Barr virus infection (CEBV), the role of EBV has been intensively studied. The etiological relationship between EBV and CFS, however, is questioned, like other lymphotropic viruses, including human retroviruses, adenoviruses and human herpesvirus 6. Additionally, severe chronic active EBV infection syndrome (SCAEBV) is also discussed in this review because symptoms of this disorder are similar to those of CFS but more severe in degree. Currently, the cause(s) and treatment of CFS are enigmatic and require further research and multidisciplinary study.

 

Source: Okano M. Viral infection and its causative role for chronic fatigue syndrome. Nihon Rinsho. 1992 Nov;50(11):2617-24. [Article in Japanese] http://www.ncbi.nlm.nih.gov/pubmed/1337559

 

Severe chronic active Epstein-Barr virus infection syndrome and adenovirus type-2 infection

Abstract:

Four patients from 4 to 24 years of age (3 males, 1 female) with generalized lymphadenopathy, hepatosplenomegaly, and intermittent fever associated with chronic active Epstein-Barr virus (EBV) infection were investigated.

Laboratory data showed polyclonal gammopathy and a tendency for bone marrow suppression. Noteworthy were the extremely elevated immunoglobulin G (IgG) antibody titers to Epstein-Barr viral capsid antigen (VCA) (range, 10,240-81,920) and early antigen (EA) (range, 1,280-40,960). All patients had IgA antibodies to VCA and EA. Subtle, heterogeneous immune functional defects were observed in all four patients. Another unusual feature was our inability to establish spontaneous or B95-8 EBV-immortalized lymphoblastoid cell lines (LCLs) due to a marked cytopathic effect (CPE). Thus, we investigated for other viruses.

Both IgG and IgM antibodies to adenovirus type-2 (Ad-2) were positive by enzyme-linked immunosorbent assay (ELISA) and immunofluorescence (IF) test, suggesting recent or activated Ad-2 infection had occurred. Dual active EBV and Ad-2 infections were likely etiologic in this severe chronic active EBV infection syndrome.

 

Source: Okano M, Thiele GM, Purtilo DT. Severe chronic active Epstein-Barr virus infection syndrome and adenovirus type-2 infection. Am J Pediatr Hematol Oncol. 1990 Summer;12(2):168-73. http://www.ncbi.nlm.nih.gov/pubmed/2165745