Introduction
Since December 2019, several cases of pneumonia caused by the novel coronavirus have been found in Wuhan, Hubei Province. The WHO has officially called coronavirus disease 2019 (COVID-19).1 The novel corona virus is linked to viruses that cause fatal acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) diseases.2 For the first time, Huang et al. registered 41 cases of COVID-19, most of which were contracted at the Huanan Seafood Market. Medical symptoms included fever, cough, dyspnea, myalgia, weakness, normal or reduced white blood cell count, and evidence of imaging pneumonia.3
There is a blood type association with rotavirus, noroviruses (NoVs), dengue virus, Norwalk virus and hepatitis B virus.4, 5, 6, 7 The type of human blood has been used as a genetic marker. By observing the relationship between the human blood type and the virus infection, it is possible to assess the susceptibility of people with different types of blood group to the virus. There is no evidence on the relationship between ABO blood typing and the incidence of COVID-19 disease in Indian population
The present study aimed to assess the relation between the ABO blood group and occurence of COVID-19 and severity.
Materials and Methods
This was a single centric retrospective study conducted at the MNR Medical College & Hospital among the patients admitted for COVID-19 infections during the July 25th to 30th October 2020. All the patients who were tested COVID-19 positive and the blood type recorded in the health care record were included in present study. The demographics, comorbidities, and the laboratory data of CBC, RBS, liver function test, renal function test, C-reactive protein, serum ferritin and D-dimer were reviewed. All procedures followed were in compliance with the ethical guidelines of the responsible committee for human experimentation (both institutional and national) and Helsinki Declaration of 1975 as revised in 2008. The comorbidities of interest which were analyzed as a binary variables were hypertension, smoking,8 hyperlipidemia, COPD, history of CAD, diabetes mellitus,9 history of cancer, chronic kidney disease, patients on dialysis10 liver disease, thyroid disorders11 and asthma were recorded. Admission referred to the admission which was primarily for the treatment and isolation specific to the COVID-19 infection. Death was defined as the mortality in which COVID-19 infection complications had a significant role in patient’s death.
Statistical analysis
All the data were entered in excel sheet and analysed using the IBM SPSS v23 operating on windows 10. The continuous data were evaluated for the normality as determined by skewness and kurtosis. The chi-square test was used for categorical variable and student’s t test was used for the continuous variables as appropriate. A p-value of <0.05 considered statistically significant.
Result
Total of 365 patients were enrolled in present study after obtaining the informed consent from all of them. Among them 53.2% were male patients and 45.8% were female patients, with male predominance. The blood group of A was common followed with blood group O and group B. 68.5% (n=250) of the patients included had turned to be positive for COVID-19 and 31.5% (n=115) were with negative COVID-19.(Table 1)
Table 1
Table 2
Blood Group |
OR |
95% CI |
Sig |
A |
1.845 |
(1.122 – 2.109 |
0.001** |
B |
1.036 |
0.753 – 1.475 |
0.71 |
O |
0.549 |
(0.357 – 0.930) |
0.01* |
AB |
0.73 |
0.41 – 1.215 |
0.30 |
There was a significant higher odds of the COVID-19 among the blood group A compared to the other blood group type and blood group O had lower odds of the disease. (Table 2)
Table 3
In 31.2% patients with blood group A had significant higher incidence with COVID-19, compared to 24.0% in blood group O, 27.6% in group B and 9.6% in blood group AB.(Table 3)
Table 4
A significant higher incidence of requirement of ventilator support was documented in 50% of the patients with group A compared to other blood group.(Table 4)
Table 5
In present study, total of 4 patients succumbed to death, and all death occurred in patients with blood group A. (Table 5)
Discussion
Blood group antigen expression differences can increase or decrease host susceptibility to a variety of infections. By acting as receptors and/or coreceptors for microorganisms, parasites, and viruses, blood group antigens can play a direct role in infection. Furthermore, through the organization of membrane microdomains, many blood group antigens facilitate intracellular uptake, signal transduction, or cell adhesion. Blood group antigens have the ability to alter the innate immune response to infection.12
Although the present study does not examine the mechanism behind the association, one possible mechanism that could be involved in the increased risk associated with the blood type A antigen is that it contains galactose as an end-group saccharide. In this position, both blood type B and O have galactose amines, which may explain the disparity between the blood types. The SARS-COV-2 spike protein has been shown to bind carbohydrates, and a close affinity between the A antigen and the virus could promote the virus' uptake in the cells.13
In present study, we have found a higher incidence of COVID-19 positive among the patients with blood Group A compared to other blood groups. Zhanna Kaidarova and colleagues discovered that individuals with blood groups A and D are more likely to develop severe disease outcomes following West Nile virus infection due to genetic susceptibility.14 The presence of histo-blood group antigens (HBGA), specifically those corresponding to the ABO, secretor, and Lewis phenotypes, is largely responsible for genetic susceptibility to norovirus.15 Rotavirus gastroenteritis was significantly more common in children with blood groups A and AB than in those with blood group O. The findings support the hypothesis that an HBGA genetic background is associated with rotavirus susceptibility.16 Cheng et al. discovered that patients with blood group O were less susceptible to SARS-CoV infection.17 According to Patrice et al., natural human anti-A antibodies may block the interaction between SARS-CoV and its receptor, thereby providing protection, which could explain why people with blood group A were more susceptible to SARS-CoV infection while people with blood group O were not.18
Also, there was a significant higher incidence of the patients with blood group A showing the requirement of the ventilator support during the course of disease, and 4 patients death was noted in study and all of them were with blood group A. The hospital stay of >7 days was frequently seen among the patients with blood Group A.
Conclusion
The current study validated the presence of higher risk of type A blood group compared to other blood group type with susceptibility for the SARS-CoV and also the severity of the progression of disease. The mortality is also higher among the patients with blood group type A. moreover, further investigations and studies are recommended to clarify and substantiate the above finding and provide better understanding at the molecular level insight related to pathogenesis and severity with blood type of patient.