Mutation of STAT1 increases susceptibility to virus infections because it is involved in various signalling pathways, including IFN-α/β, IFN- γ, IFN-l, IL-2, IL-3, IL-6, IL-9, IL-10, IL-11, IL-12, IL-15, IL-21, IL-22, IL-26 and IL-27 [10], and chemokines of several types such as C-X-C motif chemokine ligand 10 (CXCL-10), Regulated upon Activation, Normal T Cell Expressed and Presumably Secreted (RANTES)/Chemokine (C–C motif) ligand 5 (CCL-5), Monocyte Chemoattractant Protein-1 (MCP-1) [11]. This evidence concerns the gene CCL5 and viral infectious disease.