Based on these premises, this review aims to provide an overview on the role played by endoplasmic reticulum aminopeptidase 1 (ERAP1) and 2 (ERAP2), which are primarily responsible for the generation of the antigenic repertoire presented by MHC I molecules, in the control of susceptibility as well as progression of different infectious diseases [2,3]. Here, ERAP2 is linked to infectious disease.