Association between ABO, Rh blood group, and COVID-19 illness

Background: The world is struggling still with the coronavirus disease 2019 (COVID-19) pandemic 3½ years since the first case was reported in December 2019 in a small province in China. Researchers and the global health community have been working tirelessly to ascertain all possible ways to treat and before that identify and protect any susceptible populace. Among many plausible factors, blood groups have also been hypothesized as one of the associated key risk factors. Aims and Objectives: This study was conducted to check for possible association if any between blood groups and COVID-19 illness. Materials and Methods: The present study was a cross-sectional, questionnaire-based study involving general population after approval by the Institutional Ethics Committee. A total of 434 individuals participated in this study. It was a Google form-based survey shared with general Indian population consisting of questions based on demography, status of COVID-19 positivity, illness if any, requirement of hospitalization. SPSS version 28 was used to analyze the data. Chi-square or Fisher’s exact test was used to assess the association between various parameters. Results: Our study shows that blood groups A and B are more disposed to COVID-19 infection, whereas blood groups O and AB are at a significantly lower risk of COVID-19 infection. The study did not show significant impact of the Rh types. Both group system, age, sex show non-significant impact on the susceptibility, progression of disease and are not associated with susceptibility to severity. Conclusion: There is a significant association between blood groups A and B and the development of COVID-19 illness. No significant association was found with Rh type and all other parameters.