My boyfriend, now husband, was one who had a severe reaction to the swine flu vaccine. He has had serious issues with siezures, extreme headaches, TMIs, and high blood pressure ever since. His brain scans present with white matter that his physicians call mysterious. This is a physically fit active man who is 5 foot 11 inches and has never weighed over 170 lbs.
May be of help/interest, re your husband:
The Protective Effect of Quercetin on Endothelial Cells Injured by Hypoxia and Reoxygenation
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8564287/
ABSTRACT EXCERPT
Quercetin, a flavonoid present in a variety of plants, has the function of anti-inflammation and anti-oxidation.
INTRODUCTION EXCERPT
Cerebral small vessel disease (CSVD) is an umbrella term that encompasses all pathological processes involving the small vessels in the brain and refers to a group of clinical, imaging, and pathological syndromes with various etiologies containing the intracranial arterioles to venules . . . The most common symptoms include mainly new onset subcortical small infarcts, lacunar foci of vascular origin, cerebral white matter hyperintensities, microbleeds, cerebral atrophy, and enlarged perivascular spaces . . .