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.