The viral origin of ME/CFS

Experienced US researcher Prof Maureen Hanson explores the evidence for the viral connection to ME/CFS and finds no proof that multiple infections lead to ME/CFS. She sees enteroviruses as the most likely culprit and although long COVID and ME/CFS overlap more data is needed to determine if they are identical.

Excerpts from her article:

Can any infection lead to ME/CFS?

There is actually no proof that multiple different pathogens can cause ME/CFS. Yet, this hypothesis persists largely due to the overinterpretation of data from at least 2 studies. The limited evidence depends on how ME/CFS is defined.

Why is the enterovirus family the most likely culprit in ME/CFS?

History offers persuasive evidence to suspect the enterovirus (EV) family of causing ME/CFS. Both circumstantial and direct evidence exists to support such a conclusion.

What is the relationship between human herpesviruses (HHVs) and ME/CFS?

A striking number of ME/CFS patients mention an acute infection with EBV or some other human herpesvirus (HHV) as the start of their illness. Whether this is true or not is not known. If someone has a long course of mononucleosis, an additional virus that may or may not cause symptoms might be necessary for induction of ME/CFS.

Infections with HHVs are common and lifelong. Healthy people maintain viruses such as EBV in a latent state.

Reactivation of dormant HHVs as a result of onset of ME/CFS may have sometimes been mistaken for a new infection, resulting in patients believing that an HHV induced their chronic illness.

Should the post-SARS-CoV-2 infection syndromes be called “ME/CFS”?

… while it would be correct to say that someone has post-COVID illness with symptoms diagnostic of ME/CFS, referring to a post-COVID syndrome as actual ME/CFS will confuse the scientific literature and cloud clinical trials.

Recently, a study of 9,764 individuals experiencing symptoms following acute COVID-19 resulted in classification of the cases into 4 subgroups and the identification of 12 core symptoms among 44 that were considered. Unfortunately, one of the key ME/CFS symptoms—unrefreshing sleep—was not evaluated. The 12 core symptoms include ones that are not identified as core symptoms in any of the ME/CFS diagnostic criteria.

Nevertheless, the intriguing overlap in symptoms between some forms of post-COVID illness and ME/CFS suggests that disruptions in the same pathways may be occurring in both diseases, but to conclude the 2 syndromes are identical without more data, especially at the molecular level, is currently unwarranted.

Conclusion

Ignoring the abundant evidence for EV involvement in ME/CFS has slowed research into the possible dire but hidden consequences of EV infections, including persistence in virus reservoirs. Prior to the SARS-CoV-2 pandemic, the ability of RNA viruses to persist in tissues for long periods was largely ignored.

Further, recognizing that EVs are prime candidates for causing ME/CFS suggests how critical it is to pursue a relevant inquiry into this diverse virus family. Do hidden reservoirs harbor these viruses? Have they induced autoimmunity through molecular mimicry? Is it past or current infection that has resulted in the many findings of immune dysfunction in ME/CFS?

Read the full paper:

The viral origin of myalgic encephalomyelitis/chronic fatigue syndrome, by Maureen R Hanson in PLoS Pathog 19(8): e1011523. [doi.org/10.1371/journal.ppat.1011523]

Medical express: Chronic fatigue syndrome may have a post-viral infection origin