Germann et al. (2026)
- Authors: Maria Germann, Natalie J. Maffitt, Olivia A. Burton, Amn Ashhad, Anne M. E. Baker, Svetlana Cherlin, Marzieh Shahmandi, Norman Charlton, Aidan S. Baker, Boubker Zaaimi, Wan-Fai Ng, Demetris S. Soteropoulos, Stuart N. Baker, James M. S. Wason, Mark R. Baker
- Institutes: Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK
- Publisher: medRxiv
- Link: DOI
Summary
This study provides clinical evidence that home-based vagus nerve stimulation can significantly alleviate the persistent fatigue associated with Long COVID. By demonstrating that an affordable and non-invasive device can improve both subjective energy levels and objective muscle function, the research offers a scalable therapeutic option for millions of patients. It also strengthens the scientific understanding of autonomic nervous system dysregulation as a central mechanism in post-viral fatigue syndromes.
What was researched?
The study investigated the effectiveness of transcutaneous auricular vagus nerve stimulation (taVNS) for reducing fatigue in individuals with post-COVID syndrome. Researchers evaluated changes in subjective fatigue levels and objective physiological markers, such as muscle fatigue and brain excitability.
Why was it researched?
Post-COVID fatigue is a debilitating condition that affects a large proportion of patients and lacks established treatments. Researchers hypothesized that these symptoms are driven by reduced activity in the vagus nerve, which is essential for regulating the body’s metabolic and inflammatory balance.
How was it researched?
This was a single-site, single-blind, randomized controlled trial involving 114 participants with post-COVID fatigue. Participants were assigned to receive 16 weeks of daily home-based stimulation using a handheld TENS machine, either at the active vagus nerve site (tragus) or at control sites (sham/earlobe). The study utilized a crossover design where all participants eventually received the active intervention.
What has been found?
In participants who adhered to the treatment for at least one hour daily, active stimulation led to a significant 11.9-point improvement in subjective fatigue scores compared to the control groups. Additionally, researchers observed measurable improvements in peripheral muscle fatigue and a normalization of autonomic function and cortical excitability.
Discussion
A primary limitation was the high rate of non-adherence, as only a subset of the total cohort completed the daily stimulation hours required for the primary efficacy analysis. Furthermore, as a preprint, these findings have yet to undergo official peer review and should be considered preliminary.
Conclusion & Future Work
The study concludes that taVNS is a safe, feasible, and effective home-based treatment for post-COVID fatigue. These results support the use of vagus nerve modulation as a potential therapy and justify larger-scale clinical investigations.