A Narrative Review on Gut Microbiome Disturbances and Microbial Preparations in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Implications for Long COVID

Abstract

Long COVID; Myalgic encephalomyelitis; Probiotics

COVID largo; Encefalomielitis miálgica; Probióticos

COVID llarg; Encefalomielitis miàlgica; Probiòtics

Myalgic encephalomyelitis, also known as chronic fatigue syndrome (ME/CFS), and long COVID are complex, multisystemic and long-term disabling conditions characterized by debilitating post-exertional malaise and other core symptoms related to immune dysregulation resultant from post-viral infection, including mitochondrial dysfunction, chronic neuroinflammation and gut dysbiosis. The reported associations between altered microbiota composition and cardinal symptoms of ME/CFS and long COVID suggest that the use of microbial preparations, such as probiotics, by restoring the homeostasis of the brain–immune–gut axis, may help in the management of symptoms in both conditions. Therefore, this review aims to investigate the implications of alerted gut microbiome and assess the evidence supporting use of microbial-based preparations, including probiotics, synbiotics, postbiotics alone and/or in combination with other nutraceuticals in the management of fatigue, inflammation and neuropsychiatric and gastrointestinal symptoms among patients with ME/CFS and long COVID.

This research was funded by the National Institute of Health Carlos III (Madrid, Spain) within the framework of the Strategic Action Plan on Health (Grant number: PI19/00629) and co-funded by the European Union (European Regional Development Fund–ERDF 2014-2020): “A way to build Europe”. Vall d’Hebron Research Institute (VHIR) is a member of the CERCA program (Generalitat de Catalunya, Barcelona, Spain).