Mild Long-Haul 4.2 X more likely if type O blood - preprint
Blood group O and post-COVID-19 syndrome - preprint
"The prevalence of PCS was
43.2% (19/44) in the blood group O and
23.7% in non-O subjects (14/60) (p=0.036).

Download the PDF from VitaminDWiki
Type O is very common in many people

No A or B Antigens in type O blood
Type A: blood containing A antigens
Type B: blood containing B antigens
Type AB: blood containing A and B antigens
Type O: blood containing neither A nor B antigens
"What are antigens in blood? Blood group antigens are carbohydrates that are attached to proteins or lipids. An antigen is a substance foreign to the body that causes an immune response. An immune response occurs when antibodies, which are proteins in your immune system, are summoned to attack an antigen."
Interesting to note
"If you contract an infection, antibodies called memory B cells quickly reproduce and make the specific antibodies you need to destroy that antigen."
Epstein-Barr Virus (in virtually all adults) hides in memory B cells
Perhaps the extra memory B cells produced to fight COVID increase the prevalence of EVB
23 VitaminDWiki pages had LONG HAUL in the title as of March 2022
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