IL6 and susceptibility to pneumonia measurement: Relative to controls, cytokines that were significantly elevated in the pneumonia cohort at 24 and/or 48 h after inoculation (evolution phase) were IL‐1β, IL‐6, IL‐15, IL‐16, IL‐17a, IP‐10, MCP‐1, MIP‐1β, and TARC; IL‐5 was significantly elevated at 168 h (resolution phase).