IL1B and infection: Furthermore, consistent with the association of type I IFN and IL-1β responses described above, in these experiments, reduced IL-1β expression levels were positively correlated with reduced IFN-β expression levels at days 1 and 2 post-infection (Figures 5B and 5D, day 1: r = 0.56, p = 0.0063; day 2: r = 0.47 and p = 0.0235).