This is anecdotal evidence, that I have read on another thread (sorry - no links nor copying of what was written to preserve privacy of a closed medical-issues forum)

It is reported that the Astra Zenica vaccine has a positive side effect in that it can make small improvements to those suffering from Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) [ https://www.cdc.gov/me-cfs/index.html - https://www.cdc.gov/me-cfs/index.html ].  The person on the forum reported that they had seen noticeable (but modest) improvements about 2 weeks after each shot, with less "brain fog".  They also reported that in a straw poll on a ME/CFS forum about 10% of the people answering mentioned improvements in energy levels. 

This is not medical "proof" (ie. not a scientific study) but it is interesting to find positive side-effects not just negative ones.

Good news ! I noticed a possible link between long covid and ME/CFS...in symptoms. Long Q-fever also shows similarities. Still often in many countries ME/CFS is "treated" as a form of depression because there is nothing fyzical they can find...

Here in NL some long-covid cases also run into problems..."nothing medical to find" so it MUST be mental...(while a lot of tiny issues put together would create a major problem). 

The pattern in ME/CFS 90% female-indicate autoimmune disease...