CD8A and infection: Various extended reviews have summarized the main initial findings: neutralizing antibodies directed towards the region of the Spike protein that interacts with the ACE-2 receptor on the surface of cells (called Receptor-Binding Domain—RBD) can prevent infection; CD4 and CD8 T cells specific for structural and non-structural proteins are elicited in infected individuals [6,7,21], and the severity of infection is proportional to the quantity and persistence of SARS-CoV-2 in the airway system [22].