The association between different blood group systems and susceptibility to COVID-19: a single center cross-sectional study from Saudi Arabia.

Background: Since the beginning of COVID-19 pandemic, many associated factors have been investigated to clarify the susceptibility and severity among the affected individuals. Biological markers can play an important role in identification of individual susceptibility to such pandemic. Growing evidence suggest the influence of different blood group systems on susceptibility to COVID-19 virus, with a particular blood type conferring selection advantage.

Objectives: The study aimed to determine the association of ABO, Rhesus (D) and P1 blood groups with COVID-19 susceptibility in Taif city, Western Saudi Arabia.

Methods: ABO, D and P1 blood antigens were determined in 104 blood samples of COVID-19 patients versus 100 control samples using either automated immunohematology analyser or test tube method. Statistical differences between patients and control samples were calculated based on p-value where results of ≤ 0.05 were considered significant.

Results: O+ve blood group constituted the predominant type among the studied samples. Determination of P1 antigen showed significant association where Anti-P1 was positive in 76.9% of patients compared to 61.0% of controls with a P value of 0.01 conferring the susceptibility of P1+ve patients to COVID-19.

Conclusion: Although our study showed no significant association between ABO and D, and susceptibility to COVID-19, there was a significant association between P1+ve and COVID-19. P1+ve participants were 2.131 times more associated with the risk of COVID-19 infection than those with Anti P1-ve. Thus, P1 antigen can be used as a biological marker for identification of individuals susceptibility to COVID-19. It is strongly advised that such individuals should consider extra protective measures. Further studies on other contributing factors should also be considered for more scientific clarity.