Scientific research suggests a possible link between different blood groups and the likelihood of COVID-19 infection. (Image: Destina / stock.adobe.com)
Blood group and risk of corona disease
The number of infections with the SARS-CoV-2 coronavirus is steadily increasing. But why are some people infected with the new type of pathogen – and others not? Blood type could play a role here, as researchers are now reporting.
As the Federal Center for Health Education (BZgA) wrote months ago on its portal “infektionsschutz.de”, several studies suggest that blood type may influence both personal risk of infection and severity. symptoms of COVID-19. However, these scientific studies have not shown consistent results. Austrian researchers are now reporting new findings.
Comparable studies confirmed
Scientists from the University of Medicine (Med Uni) Graz are currently studying the possible link between different blood groups and the likelihood of COVID-19 infection at the University Clinic for Blood Group Serology and Transfusion Medicine. According to a press release, initial research confirms comparable studies in China and Europe that people with blood group 0 are less likely to contract COVID-19 than people with blood groups A, B or AB. Now the mechanism on which this observation is based needs to be investigated.
Causes that promote infection
Research is currently being carried out around the world into the causes that promote infection with SARS-CoV-2 or influence the course of COVID-19. The AB0 blood group appears to play a role here, as the results of a study in China and some European countries show. Red blood cells (erythrocytes) are ring-shaped cells that carry oxygen and carbon dioxide in the bloodstream. As explained in the communication, the “shell” of red blood cells is called the “membrane”. This membrane contains several different carbohydrates (sugar) and proteins which give red blood cells a certain surface structure, they are also called “antigens”.
The “blood group carbohydrates” A and B are also such antigens. For the AB0 blood group, a distinction is made between the properties A, B, AB and 0 (zero). According to experts, people with blood group “0” do not have any of these blood group antigens on the surface of their red blood cells. In people with the “AB” blood group, both carbohydrates (A and B) are contained in the erythrocyte membrane. And with the “A” blood group only the “A” antigen is present, with the “B” blood group only the “B” antigen.
Retrospective case-control study
It is known that the sugar structures, as they are in the AB0 blood group system on the cell surface of red blood cells, but also in the tissues of the respiratory organs and the gastrointestinal tract, not only in the recognition of groups blood by antibodies, but also in the recognition of microorganisms play a role. “Pathogens such as bacteria or viruses can selectively bind to the structures of blood groups and influence the colonization of affected tissues or uptake into cells,” explains Eva Maria Matzhold, study leader, molecular biologist at the University Clinic for Blood Group Serology and Transfusion Medicine, Med Uni Graz. “In our study, we are investigating whether the properties of ABO blood groups may represent a possible additional risk factor for COVID-19 infection and disease,” adds transfusion specialist Thomas Wagner.
In the first research results presented, it could already be shown that a link between the blood group and an infection with the coronavirus SARS-CoV-2 can be proven. This confirms the first indications of a study in China and a genome-wide association study (European research group GWAS COVID-19). The Med Uni Graz study is designed as a retrospective case-control study with a total of 399 people who tested positive for SARS-CoV-2 who were in hospital treatment due to COVID-19 disease.
The severity of the disease remains unchanged
“The results of our study show that people with blood group O have a statistically significantly lower probability of developing COVID-19 than people with other ABO phenotypes (blood group A, B or AB)”, report the researchers . The AB blood group, on the other hand, was found to be significantly more frequently in infected and COVID-19 patients than the frequency of occurrence in the healthy control group.
However, the severity of the COVID-19 disease is not affected by the AB0 blood group. This means that the disease is not easier in people with blood group 0 than in people with blood group AB. An AB0 blood group determination should not currently be used as a prognostic marker for the course of COVID-19. According to the researchers, the task now is to carefully research the mechanism that plays a role in this regard. Other blood group systems are also included in the surveys, the scientists explain. (a d)
Author and source information
This text complies with the requirements of specialized medical literature, medical directives and current studies and has been verified by health professionals.
Medical University of Graz: COVID-19: Focus on Blood, (accessed October 17, 2020), Medical University of Graz Federal Center for Health Education: Coronavirus: Questions and Answers: Course of the disease and immunity, (accessed October 17, 2020) ), infektionsschutz.de
This article is provided for informational purposes only and should not be used for self-diagnosis or self-treatment. It cannot replace a visit to the doctor.