The impact of the ABO/Rh blood group on susceptibility and severity among COVID-19 patients in Luanda, Angola

SARS-CoV-2 is a public health concern worldwide. Identification of biological factors that could influence transmission and worsen the disease has been the subject of extensive investigation. Herein, we investigate the impact of the ABO/Rh blood group on susceptibility and severity among COVID-19 patients in Luanda, Angola. This was a multicentric cohort study conducted with 101 COVID-19 patients. Chi-square and logistic regression were calculated to check factors related to the worsening of the disease and deemed significant when p<0.05. Blood type O (51.5%) and Rh-positive (93.1%) were the most frequent. Patients from blood type O had a high risk to severe disease [OR: 1.33 (95% CI: 0.42 - 4.18), p=0.630] and hospitalization [OR: 2.59 (95% CI: 0.84 - 8.00), p=0.099]. Also, Rh-positive blood type presented a high risk for severe disease (OR: 10.6, p=0.007) and hospitalization (OR: 6.04, p=0.026). We find a high susceptibility, severity, hospitalization, and mortality, respectively, among blood group O and Rh-positive patients, while blood group AB presented a low susceptibility, severity, hospitalization, and mortality, respectively. Our findings add to the body of evidence suggesting that ABO/Rh blood groups play an important role in the course of SARS-CoV-2 infection.