IL9 and acute respiratory distress syndrome: Elevated levels of pro-inflammatory cytokines and chemokines (e.g., TNFα, IFNγ, IL-1, IL-6, IL-8, IL-9, IL-12 IL-15, and IL-17) have been found, up to 10 days after the onset of symptoms, in the plasma of patients with acute respiratory distress syndrome (ARDS) caused by influenza A/H1N1 (Bermejo-Martin et al., 2009; To et al., 2010; Hagau et al., 2010).