People with a second blood group have an increased risk of contracting COVID-19 and developing severe COVID-19, said Brigham And Women's Hospital specialists.

The authors of the study were interested in the element responsible for binding to the host cell. They wanted to understand how the blood group affects the strength of the binding of the virus to red blood cells and epithelial cells of the respiratory tract. The strength of the ligament directly affects the severity of the infection.

It turned out that the virus showed a clear preference for antigens of the second blood group located on the epithelial cells of the respiratory tract. There was no significant difference in the degree of binding of the virus to erythrocytes in different blood groups.

The risk of severe COVID-19 has also been found to be increased in people with cardiovascular disease, elderly patients, diabetics, obese people, and carriers of the APOE gene mutation associated with Alzheimer's disease.