Furthermore, studies based on ferrets showed that influenza virus strains causing severe disease were characterized by a lesser induction of type I and II interferons [46], and monokines induced by IFN-γ (MIG) have been shown to exhibit direct antiviral properties [53] and to be essential in the development of a protective Th1 response against viral infection in the central nervous system [54]. Here, CXCL9 is linked to viral infectious disease.