Dr VanElzaker says in this video that the root cause of what presents as ME/CFs is different in each person. He says, therefore, the root cause needs to be determined.
While I think he is right about neuroinflammation being a primary cause of symptoms. I don't think that each person has a different cause. I have said this many times before, because I feel so strongly about it.
I think they have already found the primary cause but haven't been able to prove it yet on a biochemical level. ME/CFS researcher Mady Hornig has a video out explaining what she thinks is the cause of ME/CFS and how it causes mito. dysfunction, neuroinflammation, immune system dysfunction and all other symptoms.
She thinks it's gut dysbiosis and leaky gut. This is why they can't find any other pathogens causing this illness, imo. High levels of lipopolysaccharides (LPS) in ME/CFS have been found in several studies and several ME/CFS researchers have said they think the gut is the main cause of ME/CFS.
Hornig thinks toxins from the gut, including lipopolysaccharides, hydrogen sulfide and lactic acid are causing immune system dysfunction, mito. dysfunction, brain inflammation and all of our symptoms.
She says these toxins can get directly into the bloodstream from the gut but also the vagus nerve can detect inflammatory bacteria in the gut and signal the brain, causing an immune response in the brain, neuroinflammation and the sickness response.
Here is a link to the video
if you are interested.