COVID reactivates viruses in ME/CFS
Swedish researchers searched for viruses in the blood and saliva of 95 non-vaccinated ME/CFS patients and 110 healthy people following a Covid-19 infection. Dormant viruses in both groups were reactivated, but more strongly in the saliva of ME/CFS patients i.e. herpesviruses (EBV, HHV6) and endogenous retrovirus (HERV-K). ME/CFS patients are more susceptible and have stronger reactions to a Covid-19 infection. This provides further evidence for altered immune responses in ME/CFS.
Saliva antibody-fingerprint of reactivated latent viruses after mild/ asymptomatic COVID-19 is unique in patients with myalgic-encephalomyelitis/ chronic fatigue syndrome, by Eirini Apostolou, Muhammad Rizwan, Petros Moustardas, Per Sjögren, Bo Christer Bertilson, Björn Bragée, Olli Polo and Anders Rosén in Front. Immunol., 20 October 2022 [doi.org/10.3389/fimmu.2022.949787]
Research abstract:
Background:
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic disease considered to be triggered by viral infections in a majority of cases. Symptoms overlap largely with those of post-acute sequelae of COVID-19/long-COVID implying common pathogenetic mechanisms. SARS-CoV-2 infection is risk factor for sustained latent virus reactivation that may account for the symptoms of post-viral fatigue syndromes.
The aim of this study was first to investigate whether patients with ME/CFS and healthy donors (HDs) differed in their antibody response to mild/asymptomatic SARS-CoV-2 infection. Secondly, to analyze whether COVID-19 imposes latent virus reactivation in the cohorts.
Methods:
Anti-SARS-CoV-2 antibodies were analyzed in plasma and saliva from non-vaccinated ME/CFS (n=95) and HDs (n=110) using soluble multiplex immunoassay. Reactivation of human herpesviruses 1-6 (HSV1, HSV2, VZV, EBV, CMV, HHV6), and human endogenous retrovirus K (HERV-K) was detected by anti-viral antibody fingerprints in saliva.
Results:
At 3-6 months after mild/asymptomatic SARS-CoV-2 infection, virus-specific antibodies in saliva were substantially induced signifying a strong reactivation of latent viruses (EBV, HHV6 and HERV-K) in both cohorts. In patients with ME/CFS, antibody responses were significantly stronger, in particular EBV-encoded nuclear antigen-1 (EBNA1) IgG were elevated in patients with ME/CFS, but not in HDs. EBV-VCA IgG was also elevated at baseline prior to SARS-infection in patients compared to HDs.
Conclusion:
Our results denote an altered and chronically aroused anti-viral profile against latent viruses in ME/CFS. SARS-CoV-2 infection even in its mild/asymptomatic form is a potent trigger for reactivation of latent herpesviruses (EBV, HHV6) and endogenous retroviruses (HERV-K), as detected by antibody fingerprints locally in the oral mucosa (saliva samples). This has not been shown before because the antibody elevation is not detected systemically in the circulation/plasma.
Comments:
Believed and safe: A new discovery about enigmatic fatigue
“The bottom line then is that patients with ME/CFS are more sensitive and have much stronger reactions to a mild COVID-19 infection. Their dormant virus is awakened and chews up the energy and the result is more fatigue, more exhaustion and feverishness, rather than typical flu symptoms… Time and again, the power plants are shut down. And you get worse general condition and poorer immune system. Not only has it been infected by a new virus, it has also awakened an army of sleeping past sinners who are being reactivated.”
MEA: Comment
“I do hope these results are followed up, as these findings have the potential for the development of new treatments looking at boosting the antiviral immune response as well as a role in immunological tests for diagnosis.”
