The microbiome in post-acute infection syndrome (PAIS).
Guo, Cheng, Yi, Boyang, Wu, Jianyong et al. · Computational and structural biotechnology journal · 2023 · DOI
Quick Summary
This review examined how the bacteria and other microorganisms living in our bodies—particularly in the gut and mouth—may be altered in patients with prolonged illnesses following infections, including ME/CFS and long COVID. The researchers looked at existing studies to understand whether changes in these microbial communities might contribute to why some people develop long-lasting symptoms after being sick. They explored possible explanations for how these microbial changes could trigger or worsen symptoms in post-infection syndromes.
Why It Matters
Understanding microbiome changes in ME/CFS could reveal new biological mechanisms underlying the illness and identify potential treatment targets. This review provides a consolidated framework for how microbial dysbiosis might connect different post-infection syndromes, offering hope for shared diagnostic markers and therapeutic approaches applicable to ME/CFS patients.
Observed Findings
Dysbiosis patterns (reduced microbial diversity and altered bacterial compositions) are observed in both acute infections and subsequent PAIS conditions including ME/CFS and PASC
Bacterial products (lipopolysaccharides and other metabolites) may cross damaged intestinal barriers and trigger immune activation in PAIS patients
Reduced abundance of beneficial bacteria (such as butyrate-producing organisms) occurs in multiple PAIS conditions
Oral microbiota alterations parallel gut dysbiosis in some post-infection syndrome patients
Microbiome-derived metabolites involved in immune regulation appear depleted in PAIS populations
Inferred Conclusions
Microbiome dysbiosis represents a plausible common mechanism linking different infections and post-infection syndromes
Microbiome alterations may perpetuate pathologic immune responses in PAIS through bacterial metabolite depletion and barrier dysfunction
Microbiome-targeted interventions represent a potentially modifiable avenue for PAIS prevention and treatment
Future research should characterize longitudinal microbiome changes from acute infection through PAIS development to establish causality
Remaining Questions
Do microbiome changes precede symptom onset or develop secondarily as a consequence of PAIS symptoms and reduced physical activity?
What This Study Does Not Prove
This review does not prove that microbiome dysbiosis causes ME/CFS or other PAIS conditions—it identifies associations and correlations from existing studies. The review cannot establish definitive causal mechanisms or establish which microbiome changes are primary drivers versus secondary consequences of illness. Individual study limitations (small sample sizes, cross-sectional designs, methodological variation) were not systematically resolved through this synthesis.
Which specific bacterial species or metabolic functions are causal versus merely correlative in PAIS pathogenesis?
Can microbiome profiling or targeted restoration strategies effectively prevent or treat ME/CFS and other PAIS conditions in clinical practice?
How much of the microbiome dysbiosis in PAIS is attributable to the original infection versus subsequent factors like altered diet, reduced mobility, and antibiotic exposure?