The effect of ABO blood group and antibody class on the risk of COVID-19 infection and severity of clinical outcomes

Abstract

The COVID-19 pandemic has affected more than 100 million cases and caused immense burdens on governments and healthcare systems worldwide. Since its emergence in December 2019, research has been focused on treating the infected, identifying those at risk and preventing spread. There is currently no known biological biomarker that predicts the risk of infection. Several studies emerged suggesting an association between ABO blood group and the risk of COVID-19 infection. In this study, we used retrospective observational data in Bahrain to investigate the association between ABO blood group and risk of infection, as well as susceptibility to severe ICU-requiring infection. We found a higher risk associated with blood group B, and a lower risk with blood group AB. No association was observed between blood group and the risk of a severe ICU-requiring infection. We extended the analysis to study the association by antibodies; anti-a (blood groups B and O) and anti-b (blood groups A and O). No association between antibodies and both risk of infection or susceptibility to severe infection was found. The current study, along with the variation in blood group association results, indicates that blood group may not be an ideal biomarker to predict risk of COVID-19 infection.

Association Between Blood Groups and COVID-19 Outcome in Iranian Patients

“…Some studies considered that people with blood type A to be the most susceptible to the disease, and people with blood type O are less likely to develop the disease [ 13–15 , 17–20 , 24 , 27–55 ]. But other studies reported conflicting results [ 22 , 23 , 56 , 57 ], and some did not find a significant relationship between blood type and COVID-19 [ 16 , 21 , 58–60 ]. Moreover, studies reported that individuals with Rh- blood type had a lower risk of infection, intubation and death, and cases with Rh+ were more sensitive to COVID-19 [ 24 , 27–29 , 56 , 57 ].…”

The association of ABO blood group with the asymptomatic COVID-19 cases in India

“…With the growing knowledge about this disease, it is clear that there are certain risk factors associated with morbidity and mortality [7][8][9]. More importantly, many of the studies have found strong association of the ABO blood group and COVID-19 with morbidity and mortality [6,[10][11][12][13][14], whilst, a few studies have also found no association of COVID-19 with the ABO blood group 10, 15,16]. In the past, there have been several studies suggesting the association of ABO blood group with diseases.…”

Host polymorphisms and COVID-19 infection

“…A higher risk in blood group A was observed than in other blood groups, whereas blood group O showed a protective effect [119] . Other groups have identified subjects with blood type B as the most vulnerable group [128] . In comparison with the higher risk of severe illness or death of blood group types A and AB, there is an agreement about the protective factor against SARS-CoV-2 infection of people with blood group O [125] , [126] , [127] , [129] , [130] , [131] .…”