ABO Blood System Associated with Susceptibility, and Rhesus (Rh) Status Associated with Disease Severity in COVID-19 Patients, (Southeast of Iran)

Background: The ABO/Rh blood groups were related to susceptibility to numerous infectious and non-infectious diseases. Here, the association of ABO/Rh groups with susceptibility to COVID-19 and disease severity was investigated in a population from southeast Iran. Material and Methods: In this descriptive study, information regarding the clinical characteristics and ABO/Rh blood groups was collected from 524 patients with COVID-19 from March to October, 2020. The data of blood groups from patients were compared with those from 7365 healthy individuals during the same period. Data was analyzed using SPSS. Results: No significant differences were found between COVID-19 patients and the healthy group regarding the proportions of A, B, and O blood groups. However, the proportion of the AB blood group was significantly higher in COVID-19 patients than that in healthy people (11.8% versus 8.2%, P 0.004). When the A group was considered as a reference, the AB blood group was associated to a greater risk of COVID-19 [OR: 1.45 (1.06-1.98), P 0.02]. No association was found between ABO blood groups and COVID-19 severity. The proportion of the Rh-positive blood group was slightly higher in COVID-19 patients than in the other group. The proportion of Rh-negative patients was greater in severe COVID-19 than in mild and moderate forms (P 0.001). In A, AB, and O blood groups, the proportions of Rh-negative patients were greater in severe COVID-19 than those with mild and moderate disease (P=0.05, P 0.05, and P 0.001, respectively). Conclusion: The AB blood group was associated with greater susceptibility to COVID-19, while Rh-negative status was positively associated with disease severity.