Not completely following your logic.
The simple question is, which virus do we treat? EB on it's own is fairly benign. Most recover.
Well first of all, the evidence of retroviral involvement in ME/CFS is very slim at this stage, so we are talking about a retrovirus that exists as a theoretical concept, but not in terms of any solid empirical evidence. Whereas active EBV or enterovirus infections in ME/CFS are empirical facts.
But even if we assume the existence of a retrovirus in ME/CFS, the question of which to treat, the retrovirus or the opportunistic infections like enterovirus, EBV or other herpes family viruses, mostly comes down to what drugs are available that target these viruses. If there are no drugs available, then you can't treat a viral infection. If there were drugs available to target both the retrovirus and the opportunistic infections, that would probably be the most efficient course of action (the more causal factors you can address, the more likely you are going to get improvements in health).
The reason people have speculatively used tenofovir and raltegravir for ME/CFS is because these two antiretrovirals happen to target feline leukemia virus. Refs:
1 2 And raltegravir targets murine leukemia virus. Ref:
1 A antiretroviral drug called elvitegravir (Vitekta) is also antiviral for murine leukemia virus. Ref:
1
Both feline leukemia virus and murine leukemia virus are from the
gammaretrovirus genus, along with XMRV. XMRV itself is a man-made virus, accidentally created in a lab in the mid-1990's by a fluke recombination event in a mouse, meaning it cannot be the historical cause of ME/CFS, a disease we know existed for many decades before the 1990s.
However, it is interesting to note that in 2001 Sidney Grossberg found a virus called the JHK retrovirus (from the murine leukemia virus family) in
one ME/CFS patient (yes, in just
one patient, so very little evidence of an association to ME/CFS at this stage). Grossberg's latest paper is
this one. So the idea of a murine leukemia virus in ME/CFS remains.
Other antiretrovirals have no known effect against feline/murine leukemia viruses.
But for me, given that a this stage, a retrovirus in ME/CFS only really exists as a speculative concept, my bet would be that the benefits of tenofovir and raltegravir for ME/CFS come from the known antiviral effects that raltegravir has on herpes family viruses (viruses known to exist and to be active in ME/CFS), and the known immunomodulatory effects of tenofovir, which possibly may help to clear enterovirus infections (known to exist and to be active in ME/CFS).
By the way, its not really true to say that EBV on its own is fairly benign, because many researchers think EBV is the cause of multiple sclerosis (and there's good empirical evidence for this). And EBV is also linked to:
autoimmune diseases, breast cancer, Burkitt's Lymphoma, esophageal cancer, Hodgkin's lymphoma, nasopharyngeal carcinoma (EBV is a known cause of this), chronic obstructive pulmonary disease, seasonal
affective disorder and lupus.
Likewise, enteroviruses are linked to:
amyotrophic lateral sclerosis, ADHD, autoimmune diseases, carcinoid tumors, Crohn's disease, diabetes mellitus type 1, diabetes mellitus type 2, dilated cardiomyopathy, Guillain–Barré syndrome, hypertension, myocardial infarction and schizophrenia.
Source:
List of Chronic Human Diseases Linked To Infectious Pathogens