There would be a link between blood type and vulnerability to coronavirus. So at least several scientific studies show. Recently, American researchers noticed that group A could be the most exposed …
Since 2020 and the advent of Covid-19 in our lives, many researchers have questioned the relationship between blood types and susceptibility to the virus.
Thus, multiple trials on the subject have emerged, and researchers have regularly been able to show that, depending on their affiliation to a particular blood type, some people are less likely to develop severe Covid-19 or even have a contract. .
On Wednesday, March 3, the results of a new study were presented in a specialized American journal Blood progression , Dr. Sean R. Stowell and his team from Harvard Medical University. If we believe that the results have been published in public, the coronavirus is more “attracted” to the respiratory cells of people with blood group A.
Group A more exposed?
The researchers were interested in the protein found on the surface of the SARS-CoV2 virus, the virus that causes Covid-19. They analyzed the interactions of this protein, called RBD (receptor blinding domain), with synthetic antigens from respiratory cells and red blood cells of different blood groups: A, B and O.
They then realized that RBD prefers binding to a synthetic antigen found in the lungs of people with blood type A. “Interestingly, RBD, a viral protein, really prefers the type of blood type A antigen found on respiratory cells,” says Professor Sean R. Stowell, one of the study’s lead authors. This is most likely the way the virus enters and infects most patients. “
In contrast, the protein does not appear to prefer red blood cells in one group over another. If these first observations confirm the possibility “Influence of blood group on Covid-19 infection”, the doctor and his team prefer to remain vigilant. “Our observation is not the only mechanism responsible for what we observe clinically,” help Sean R. Stowell.
Further studies that follow
Telephone available, Nantes immunologist Jacques Le Pendu, director of research at Inserm and the University of Nantes, who also worked on the correlation between blood types and Covid-19, is also cautious about advertising the results. “This study remains very preliminary, the conclusion is hasty. Raw data is missing “, he believes.
Nevertheless, the study paves the way for further research on the topic of blood types. In France, Jacques Le Pendu and his team have already analyzed nearly forty publications interested in the links between Covid-19 and blood types.
In January, he uncovered several hypotheses, according to analyzes: natural antibodies against A and anti B (only both O) can partially protect against SARS-Cov-2 infection, and people of blood group O are less likely to develop thrombosis (the formation of blood clots that prevents good blood circulation in very severe forms of Covid-19). But nothing predicts a riskier exposure of people from group A.
The French researcher claims that the susceptibility of the virus to blood group A has not been proven so far, but that blood group antibodies could play a role in limiting the risk of infection. “We worked on it [la préférence] in May and failed. We will look at it again with my team “, announces.
Really privileged group O?
According to various studies that already exist, two different effects appear to favor people with blood type O. “ The first is that antibodies against A and B could play a protective role. “
Recall, people in group O develop antibodies against A and B, and A develop antibodies, B the opposite, and AB has no antibodies. Thus, group O appears to be less exposed to SARS-CoV-2.
“The second effect is seen in the development of severe forms of the disease. When you are in intensive care, it is obviously better to be in group O, explains Nantes’ immunologist. It has long been known that the risk of clotting is reduced in people with blood type O, hence the risk of thrombosis. “
Which blood type do other viruses prefer?
If a U.S. study improves, still a little too soon, the highest risk of group A infecting Covid-19, the susceptibility of the virus to a particular blood type is no exception. This is especially the case with noroviruses. “In winter, they cause gastroenteritis, and people are recognized by their blood type, adds Jacques Le Pendu. But it is variable, some strains prefer group A, others O, others B … And others don’t care! ” So, faced with gastroenteritis, don’t rely on your blood type to protect you!
On the other hand, for pediatric gastroenteritis, caused by “rotavirus,” group O appears to once again appear privileged. “Strains that normally circulate in France due to gastroenteritis in young children appear to be much less at risk than blood type O.”