At the Lymph Balance Centre we provide Lymph Drainage Therapy, Brain Therapy and a CFS Protocol to help those with ME/CFS/FM and Long COVID symptoms.  We have had good clinical experience in the past year with minimizing brain fog, sleep concerns as well as asnomia (absence of smell/taste). 
There are many overlaps of symptoms between Long COVID-19 and Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), including post-exertional malaise, fatigue and reduced daily activity (1).
A study found that 89.1% of participants with Long COVID-19 experienced post-exertional malaise, which is generally considered a defining symptom of ME/CFS (2).
A German study found that approximately half of all Long COVID-19 patients fulfilled the diagnostic criteria for ME/CFS (3).
The similar symptoms of ME/CFS and Long COVID-19 may reflect similar underlying pathological processes including infection and inflammation of the central nervous system, and a dysregulated immune system.
A new taxonomic classification has been proposed called “Post-Active Phase of Infection Syndromes” or PAPIS (4).
1. Pheby D, Friedman K, Murovska M, et al. Turning a Corner in ME/CFS Research. Medicina (Kaunas). 2021 Oct; 57(10): 1012.
2. Davis H., Assaf G., McCorkell L, et al. Characterizing Long COVID in an international cohort: 7 months of symptoms and their impact. EClinicalMedicine. 2021;38:101019. 
3. Kedor C., Freitag H., Meyer-Arndt L. Chronic COVID-19 Syndrome and Chronic Fatigue Syndrome (ME/CFS) following the first pandemic wave in Germany—A first analysis of a prospective observational study. medRxiv. 2021.
4. Friedman K., Murovska M., Pheby D., et al. Our Evolving Understanding of ME/CFS. Medicina. 2021;57:200.
https://solvecfs.org/me-cfs-long-covid/what-is-long-covid/