@Hip: thanks for the info on the trigeminal nerve. I never knew about the sinusitis - neuro link through it (I'd assumed that if there could be an interface that it would be meditated by the vagal nerve like most other organs, but anatomically this obviously didn't really make sense)
Yeah, I read this interesting stuff about the trigeminal nerve also being able to trigger brain inflammation and sickness behavior in the following study:
From inflammation to sickness and depression: when the immune system subjugates the brain
"The brain monitors peripheral innate immune responses by several means that act in parallel. One pathway involves afferent nerves: locally produced cytokines activate primary afferent nerves, such as the vagal nerves during abdominal and visceral infections, and the trigeminal nerves during oro-lingual infections."
So both the vagus and trigeminal nerves can detect infection/inflammation in the peripheral areas of the body, and then as a result trigger inflammation and sickness behavior in the central nervous system.
Sickness behavior has symptoms very close to those of ME/CFS.