The first animal models described lacked signaling either to all the three types of interferons (STAT-1−/−)75 or type 1 interferon (IFNAR−/−).76 Besides the knockout mice, a mouse model whose type 1 interferon system is temporarily suppressed IS has been described.77 The knockout models and the (IS) model are permissive to infection, succumbing to CCHFV infection within 5 days. Here, STAT1 is linked to infection.