IFNB1 and viral infectious disease: This information may suggest that not only the higher IFN-β levels observed in the Allele-2 group may be useful for controlling CMV infection but also that the positive correlation between IgG levels specific for SARS-CoV-2 and IFN-α2 or the IFN-α2/IL-10 ratio may benefit the immune response to viral infection and vaccination, demonstrating a putative link between the IFNλ polymorphism and type I IFNs in the study.