Cytomegalovirus, Epstein-Barr Virus and Human Herpesvirus 6 Infections in Patients with Myalgic Еncephalomyelitis/Chronic Fatigue Syndrom

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a disabling multisystem chronic disease. The etiology and pathogenesis of ME/CFS are unknown. Infections of cytomegalovirus (CMV), Epstein-Barr virus (EBV) and human herpesvirus-6 (HHV-6) are suspected as etiological agents for ME/CFS. This study aims to estimate prevalence and type (active/latent) of EBV, CMV and HHV-6 infections in Bulgarian ME/CFS patients.

In the study were included 58 ME/CFS patients and 50 healthy controls. Virus-specific antibodies were detected by ELISA and viral genomic sequences in PBMCs and plasma samples – by nPCR. We did not observe any significant differences in virus specific IgG and IgM positivity rates between ME/CFS patients and control group. In ME/CFS plasma samples EBV DNA was found in 24.1%, CMV DNA – in 3.4% and HHV-6 DNA in 1.7% of samples. EBV DNA was detected in 4%, CMV and HHV-6 DNA were not found in plasma samples of controls. The frequency of viral genome detection in PBMCs of patients and controls was 74% vs 78% for CMV, 81% vs 84% for EBV, and 82.8% vs 82% for HHV-6. The difference in frequency of EBV active infection in ME/CFS and control group was statistically significant (p=0.0027). No ME/CFS and control individuals with active CMV and HHV-6 infection were observed.

In conclusion, our study using both serological and PCR-based techniques for distinguishing between active and latent infection, showed high rate of active EBV infection among ME/CFS patients indicating that at least in a subset of cases EBV is important factor for development of disease.

Source: Shikova E, Reshkova V, Kumanova А, Raleva S, Alexandrova D, Capo N, Murovska M; European Network on ME/CFS (EUROMENE). Cytomegalovirus, Epstein-Barr Virus and Human Herpesvirus 6 Infections in Patients with Myalgic Еncephalomyelitis/Chronic Fatigue Syndrome. J Med Virol. 2020 Mar 4. doi: 10.1002/jmv.25744. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/32129496

Chronic fatigue syndrome: I. Epstein-Barr virus immune response and molecular epidemiology

Abstract:

Patients with chronic fatigue syndrome were compared to healthy seropositive control subjects in an open study and a case-control study analyzing spontaneous transformation rates of peripheral blood lymphocytes, EBV viral genome characteristics as determined by DNA restriction fragment polymorphisms, and antibody production by Western blot analysis.

Thirty percent of patients versus 8% of control subjects underwent spontaneous transformation in the two studies. Viral genome patterns were overall similar to one another, with polymorphisms frequently present in BamHI B’, K, H, and Y fragments. Only one line was found with the EBNA-2B genotype.

Nineteen lines were found to contain viral DNA in the linear form suggesting active lytic replication. Western blot studies suggested that ill subjects made antibodies to lytic proteins more frequently than did healthy control subjects. Lack of control of EBV outgrowth in vitro is correlated with antibody evidence of active infection in vivo in some patients with chronic fatigue syndrome.

 

Source: Jones JF, Streib J, Baker S, Herberger M. Chronic fatigue syndrome: I. Epstein-Barr virus immune response and molecular epidemiology. J Med Virol. 1991 Mar;33(3):151-8. http://www.ncbi.nlm.nih.gov/pubmed/1679118