People with those diagnosis are ill, often very ill. The name is what is very incorrect. In some cases, doctors and patients cling to the name for reasons such as “Lyme can be treated, but Chronic Fatigue cannot!” – just as they will say “You will be all right (when they know the odds are that the patient will not live)”.
A year ago, I did a review of Chronic Lyme, and stated ” I believe that Post Infection Fatigue Syndrome is a better approach for treatment success.” The key factor is there is no ability to tell these different ascribed names via lab tests — especially with long term patients.
“This post-infective fatigue syndrome phenotype was stereotyped and occurred at a similar incidence after each infection. The syndrome was predicted largely by the severity of the acute illness rather than by demographic, psychological, or microbiological factors.”  Post-infective and chronic fatigue syndromes precipitated by viral and non-viral pathogens: prospective cohort study.
This has been in the literature since at least 1987 Post-infectious fatigue. “an illness characterized by persisting fatigue and disability after apparent acute infections. In most cases the illness is attributed to a chronic Epstein-Barr virus infection.”
In the literature on PubMed you will find:
- Post-giardiasis chronic fatigue syndrome  “cases that developed CFS after Giardia infection compared to cases that recovered well.”
- Post-mononucleosis[EBV] chronic fatigue  “Chronic Fatigue Syndrome (CFS) has been known to follow Epstein-Bar virus (EBV) and other systemic infections;”
- “the role of the herpesviruses EBV, CMV and HHV-6 in post-infective fatigue syndrome .
- [Post-Lyme disease syndrome] 2016.
- Chronic fatigue syndrome following a toxic exposure . – five patients
- Q fever: persistence of antigenic non-viable cell residues of Coxiella burnetii in the host–implications for post Q fever infection fatigue syndrome and other chronic sequelae .
- Chronic fatigue syndrome after Q fever .
- “These results suggest the possibility of direct involvement of C. burnetii in the pathological state of CFS to be low, despite the C. burnetii infection rate being high in CFS patients” 
- Post-infective and chronic fatigue syndromes precipitated by viral and non-viral pathogens: prospective cohort study .
- Post-infectious fatigue syndrome in dengue infection .
- Chronic fatigue syndrome (CFS) associated with Staphylococcus spp. bacteremia, responsive to potassium arsenite 0.5% in a veterinary surgeon and his coworking wife, handling with CFS animal cases .
I have personally met a post-leprosy chronic fatigue patient (leprosy is cause by the same family of bacteria as lyme).
Retreating Treatment rarely has success
- “Despite treatment with doxycycline, he continued to have markedly elevated Coxiella burnetii phase I antibody titers for 10 years after the initial diagnosis.” 
With so many different diseases — what is in common?
The answer is simple — the diseases alter the microbiome. This alteration causes many of the symptoms. If this alteration get ‘stuck’, the symptoms will continue.
” However, the altered microbiome, in turn, may aggravate the disease, as it has the potential to overproduce toxic substances such as ammoniac and GABA, and to impact manganese metabolism; all three are thought to play a role in hepatic encephalopathy . Interestingly, treatments that are currently used, laxatives, antibiotics, and enemas, actually target the microbiome. The benefits are only temporary, likely because they do not prevent the reconstitution of the harmful microbiome; a more permanent modulation could be sought as a novel way to treat this disease.” 
Microbiome-wide association studies link dynamic microbial consortia to disease 
Shifts of the microbiome also happens with stress.
So what is the right name?
- Post-infection… is not correct, because it excludes those that slipped into CFS from stress…
- Chronic Fatigue .. this name is already problematic.
- “Off-stomach” .. while better, people will not the persistent aspect
- Microbiome Dysfunction Disease .. unfortunately, Crohn’s, IBD would be included.
- “Bell-Cheney Disease” — after Dr. Bell and Dr.Cheney! This is my favorite suggestion.