Relationship between blood group and COVID-19

A series of studies have examined a potential relationship between blood group and COVID-19. Initial research conducted by scientists in Wuhan, China, on thousands of infected patients suggested that individuals with blood group A were more likely to experience severe symptoms of COVID-19 infection compared to those with blood group O. Other blood types fell between these two in terms of relative risk.

Source: Wikipedia — Relationship between blood group and COVID-19 (CC BY-SA 4.0)