IFNA2 and infection: This postulation is supported by the observation that Irf7−/− mice produce little to no systemic IFNα activity when infected with a number of viruses, including Dengue virus (DENV), herpes simplex virus 1 (HSV-1), and encephalomyocarditis virus (EMCV), and this loss of systemic IFNα activity correlated with increased susceptibility to those infections (34, 110, 111).