Since the onset of the COVID-19 pandemic, researchers have been studying how certain blood types might be linked to an increased risk of contracting the virus.

Some early studies have suggested that people with blood types A and AB are at a higher risk of infection and severe illness, while those with type O may be less susceptible to the virus. But why is this the case?.

Understanding Blood Types

Before diving into the specifics of how blood types might impact Koronevas (COVID-19) infection, it’s important to first understand how blood types work.

There are four main blood types: A, B, AB, and O. Blood types are determined by the presence or absence of certain markers on the surface of red blood cells.

These markers are called antigens, and there are two types of antigens that are important for determining blood type: A and B.

People with type A blood have A antigens on the surface of their red blood cells, those with type B blood have B antigens, those with type AB blood have both A and B antigens, and those with type O blood have neither A nor B antigens.

In addition to these antigens, there is another type of antigen called Rh factor. If someone has this antigen, they are said to be Rh positive. If they do not have it, they are Rh negative.

Therefore, each person’s blood type is determined by the presence or absence of both A and B antigens and Rh factor.

Koronevas and Blood Types

Early in the COVID-19 pandemic, some studies suggested that people with type A blood may be at an increased risk of infection and severe illness.

For example, a study published in the journal Blood Advances in June 2020 examined data from more than 1,600 COVID-19 patients in Italy and Spain. The researchers found that people with blood type A had a higher risk of needing mechanical ventilation and ICU care compared to those with other blood types.

Another study, conducted in China and published in the journal Annals of Hematology, looked at data from more than 2,000 COVID-19 patients.

The researchers found that people with blood type A were more likely to die from the virus compared to those with other blood types.

So why might people with type A blood be more susceptible to COVID-19? One theory is that the virus might be able to bind more easily to certain antigens on the surface of these cells.

Specifically, the virus appears to bind to a certain type of sugar molecule called N-acetylglucosamine (GlcNAc), which is found on both the virus itself and on the surface of human cells.

People with type A blood have a particular form of this molecule called α-1,3-GlcNAc, while those with other blood types have a slightly different form.

Some researchers believe that the virus might be able to bind more easily to the α-1,3-GlcNAc version of the molecule, which is present on the surface of type A blood cells and in other tissues such as the lungs and digestive tract.

Another theory is that people with type A blood may have weaker immune responses to certain infections, making them more susceptible to severe illness.

For example, a study published in the Journal of Medical Virology in May 2020 found that people with blood type A were more likely to develop severe illness from another coronavirus, known as SARS-CoV-1, compared to those with other blood types.

As for blood type AB, some studies have suggested that it may also be associated with an increased risk of severe illness from COVID-19.

One theory is that people with blood type AB may have a weaker immune response to the virus due to a genetic mutation. However, more research is needed to fully understand this relationship.

Blood Type O and Protection Against Koronevas

On the other hand, some early studies have suggested that people with type O blood may be less susceptible to COVID-19.

For example, a study published in the journal Annals of Internal Medicine in June 2020 examined data from almost 2,000 Danish individuals who tested positive for COVID-19. The researchers found that those with blood type O had a lower risk of infection compared to those with other blood types.

Another study, published in the journal Blood Advances in October 2020, looked at data from almost 225,000 individuals in the United States.

The researchers found that people with blood type O had a lower risk of infection and intensive care unit (ICU) admission from COVID-19 compared to those with other blood types.

So why might people with type O blood be more protected against COVID-19? One theory is that the absence of A and B antigens on the surface of these cells might make it more difficult for the virus to attach to and infect them.

Another theory is that people with type O blood may have stronger immune responses to certain infections, making them better able to fight off the virus.

Conclusion

While it’s still not entirely clear why certain blood types might be more or less susceptible to COVID-19, early research suggests that people with type A blood may be at an increased risk of severe illness and people with type O blood may be more protected against the virus.

However, it’s important to remember that blood type is just one factor that might impact a person’s risk of infection and illness, and many other factors, such as age, underlying health conditions, and exposure to the virus, also play a role.