While systemic administration of LPS causes sepsis, including septic encephalopathy, which is pathologically similar to IAE in terms of the involvement of inflammatory cytokines including TNF-α, IL-6, IL-1β, type I IFNs26,27,39, and type II IFN35,36, our study clearly demonstrates that influenza virus infection prior to systemic administration of LPS exacerbated brain edema. This evidence concerns the gene IL1B and Sepsis.