Interesting laboratory study on how blood type A antigens on respiratory cells’ surface may provide another way for SARS-CoV-2 to enter the body increasing infection risk. However, no clinical outcome data as this looked only at in vitro effects.

Medical Mythbusting Commentary for March 9, 2021

Why blood type A may increase COVID-19 risk

The SARS-CoV-2 receptor-binding domain preferentially recognizes blood group A