We observed the most pronounced protective effect of early IFNAR blockade in C57BL/6 mice at 20 days after infection, when the lung CD4+ T cell response is still in its early stages, with only modest reductions in lung CFU observed when analyzed at the later 28-day time point, the latter in keeping with past reports (Ji et al., 2019; Mayer-Barber et al., 2011; Moreira-Teixeira et al., 2017; Moreira-Teixeira et al., 2016). Here, CD4 is linked to infection.