Scientists have uncovered new evidence that suggests that people with blood type A may be more likely to contract COVID-19.
The new study was published in the journal Blood Advances on Wednesday.
"Despite the devastating consequences of SARS-CoV-2, not all individuals seem to be equally susceptible to contracting the virus," the study said.
The researchers examined the receptor-binding domain (RBD), a protein on the surface of the SARS-CoV-2 virus that attaches to the host cells.
They then looked at how the RBD interacted with a variety of respiratory and red blood cells from A, B and O blood types.
"No significant binding was observed toward the type II structures of A, B, or O(H) individuals. In contrast, the SARS-CoV-2 RBD exhibited high preference for the same type of blood group A (type I) expressed on respiratory epithelial cells."
The scientists said this may provide some insight into the apparent preference of COVID-19 and potentially other severe coronaviruses for people who have blood group A.
Study author Dr Sean Stowell, from Brigham and Women's Hospital in Boston, said in a press release that the results were "interesting".
"Blood type is a challenge because it is inherited and not something we can change," he said. "But if we can better understand how the virus interacts with blood groups in people, we may be able to find new medicines or methods of prevention."
However, the scientists said more research is needed to predict how coronaviruses would affect people with different blood types."Our observation is not the only mechanism responsible for what we are seeing clinically, but it could explain some of the influence of blood type on COVID-19 infection," the team said.