We found that Ifng, but not Ifna or Ifnb, was highly upregulated in OBs early after infection, but surprisingly found that, unlike IFN-I, IFN-γ was required for the efficient replication of JHMV in mice, as JHMV WT and N1347A replication was dramatically reduced in IFN-γ-/- and IFN-γR-/- mice. Here, IFNB1 is linked to infection.