To monitor cytokine responses during the later course of primary RSV infection, cytokines and chemokines were measured in lung samples of RSV infected wild type (wt) and Mavs−/− mice, starting 4 days post infection (p.i.)up to day 9 p.i. The relative gene expression of Tnfa, Il6, and Il1b, and the protein expression of chemokine CCL2 were all detected on days 5 to 7 p.i. in both wt and Mavs−/− mice (Figures 1A, B). Here, IL6 is linked to infection.