Thus, our findings indicate that in healthy individuals whose immune system responded properly to the vaccination against the SARS-CoV-2 S protein, the humoral and cellular immunity that developed early on are specific and durable; however, a small but far from negligible proportion of people, around 15%, did not develop a T cell response, regardless of their age or known history of immunodeficiency. Here, PROS1 is linked to immunodeficiency disease.