Groups of A129 IFNAR−/− mice were infected with 105 FFU of wt SFTSV, and administered either an anti-IL-6 antibody (2B Scientific; BE0046) or an isotype control antibody (BioXCell; BP0089) at PID −2 (prophylactic, before infection; Fig.   6a) or at PID 2 (therapeutic, after infection; Fig. 6b). Here, IL6 is linked to infection.