In Covid-19, people who are part of blood groups A and AB are more at risk of developing lung and kidney failure than those of group O.
- It is increasingly recognized that ABO blood groups influence susceptibility to certain viruses, including SARS 2003 and noroviruses.
- Patients with blood group A or AB required mechanical ventilation and continuous renal replacement therapy more often than members of blood group O.
- This difference is played out at the time of infection.
People with blood group O are better protected from Covid-19 than others. Two studies reveal that these people are not only less likely to be infected with the virus, but they are also less likely to develop a severe form. The first study was conducted by a team of Danish researchers and the second by Canadian colleagues. This work also shows that groups A and AB more often have lung and kidney failure. The results of both studies were published on October 14 in the journal Blood Advances.
Less infected, less severely and less long-lasting O
The coronavirus is not the first virus to act differently on a person’s body depending on their blood type. “It is increasingly recognized that ABO blood groups influence susceptibility to certain viruses, including SARS 2003 and noroviruses”, reported the Danish authors. For this study, the researchers analyzed the medical records of more than 470,000 patients who took a PCR test. In total, there have been more than 7,400 positive cases. “Among people with Covid-19, we found significantly fewer people in group O”, observed the authors.
The other study, carried out by the Canadian researchers, examined the cases of 95 patients placed in intensive care in six hospitals following severe forms of Covid-19. She revealed the fact that the virus attacks several organs, such as the liver and the kidneys. “If ABO blood types play a role in determining disease severity, these differences should manifest within multiple organ systems.”, added the researchers who found that patients with type A or AB more often required mechanical ventilation and continuous renal replacement therapy than members of blood type O. They also saw their stay at the hospital be longer. “Our data indicate that critically ill patients with blood type A or AB are at higher risk of needing mechanical ventilation, CRRT and prolonged ICU admission than patients with blood type O or B”, they concluded.
Everything happens at the time of infection
According to the authors, the difference is played out when the cells are infected by the virus. It is the presence, or absence, of certain molecules on our red blood cells which is the cause. For people with blood group A, A molecules are present. For group B people, these are B molecules but for O people, there is neither of these two molecules. Any missing molecule is considered by the immune system to be fought. People in group A will therefore develop anti-B antibodies, people in B anti-A antibodies. Type O people will develop antibodies against both. Previous studies have shown that it is the anti-A and anti-B antibodies that interfere with the virus and prevent it from entering the body. Since people in group O have both, the researchers believe that this is what gives them additional protection.
.
