Long covid has been generally, if covid hit your nervous system where it buried and/or released an old disease l like mono,herpes,shingles,etc. There are many cases before vaccination. With that said vaccination are known to create the condition. It seems tied to the spike protein doing more than simple flu stuff. The FLCCC have been looking into this for years now.
https://covid19criticalcare.com/treatment-protocols/i-recover-long-covid-treatment/
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