IFNAR1 and infection: Notably, favipiravir has been confirmed to provide a complete protection against the lethal SFTSV infection for Stat2–/– hamsters in accord with the conclusion drawn from Ifnar–/– mice, while ribavirin that provides protection for Ifnar–/– mice is ineffective for Stat2–/– hamsters against SFTSV (Shimada et al., 2015; Tani et al., 2016, 2018; Yoshikawa et al., 2019).