The role of enterovirus in chronic fatigue syndrome

Abstract

Two and a half decades after coining of the term chronic fatigue syndrome (CFS), the diagnosis of this illness is still symptom based and the aetiology remains elusive. Enteroviruses are well known causes of acute respiratory and gastrointestinal infections, with tropism for the central nervous system, muscles, and heart. Initial reports of chronic enteroviral infections causing debilitating symptoms in patients with CFS were met with skeptism, and had been largely forgotten for the past decade. Observations from in vitro experiments and from animal models clearly established a state of chronic persistence through the formation of double stranded RNA, similar to findings reported in muscle biopsies of patients with CFS. Recent evidence not only confirmed the earlier studies, but also clarified the pathogenic role of viral RNA through antiviral treatment. This review summarises the available experimental and clinical evidence that supports the role of enterovirus in chronic fatigue syndrome.

Chronic fatigue syndrome

“…Antibodies to coxsackie B virus are frequently detected in CFS patients, and enterovirus protein and RNA occur in the muscle and blood of CFS patients (Yousef et al, 1988;Gow et al, 1991;Clements et al, 1995), and their presence has been associated with altered metabolism in the muscle upon exercise in the context of CFS (Lane et al, 2003). Viral persistence through the formation of stable double stranded RNA may explain the apparent discrepancy between an absence of live virion in chronically infected patients and animals along with the presence of enteroviral RNA in the blood or other tissues (Chia, 2005). In addition, interferon-␣ and interferon-␥ act synergistically against enterovirus in vitro, and preliminary studies suggest that this combination may be an effective treatment for patients with chronic enteroviral infection (Chia, 2005).…”

“…First, it has been possible to confirm the presence of infection in patients with CFS patients who present to the clinic many months after the onset of their illnesses (Chia and Chia, 2003). Second, outbreaks of CFS have been documented which have been shown by laboratory investigation to be caused by outbreaks of particular infectious agents, for example, with C. burnetii and enteroviruses (Ayres et al, 2002;Chia, 2005). Third, when a cohort of patients suffering from acute infection with a particular infectious agent are followed in time, a subset of these have been shown to develop CFS with an onset contemporaneous with the onset of the particular microbial infection.…”

Evaluation of immunohistochemistry and in situ hybridization methods for the detection of enteroviruses using infected cell culture samples

“…polio myelitis). Enterovirus infections may also play a role in chronic diseases such as dilated cardiomyopathy, 1-3 chronic fatigue syndrome 4 and type 1 diabetes. 5 found in heart tissue in chronic cardiomyopathies and in the pancreas and intestine of type 1 diabetic patients using immunohistochemistry (IHC), in situ hybridization (ISH), RT-PCR and virus isolation.…”

High Prevalence of Human Enterovirus A Infections in Natural Circulation of Human Enteroviruses

“…Although the majority of Human enterovirus (HEV) infections are asymptomatic, enterovirus infections can cause upper respiratory illness, febrile rash, aseptic meningitis, pleurodynia, encephalitis, acute flaccid paralysis, and neonatal sepsis-like disease (35). HEV may also be implicated in the pathogeneses of severe chronic diseases, including type 1 diabetes mellitus (33), myocarditis and congestive cardiomyopathy (20), and neuromuscular diseases (8).…”