CXCL9 and susceptibility to pneumonia measurement: Analysis of expression changes in DEGs in the pneumonia and bronchitis cases (|log2FC| ≥ 2) showed that numerous genes were upregulated in the pneumonia cases, including interferon-stimulated genes (ISGs) (IFITM3, IFITM10, and IFIT5) involved in innate immune responses, and pro-inflammatory cytokines/chemokines (CXCL1, CXCL9, IL-1a, CXCL16, CXCL3, and IL6R), and IL-1R3 genes that play multi-functional roles in inflammatory diseases (Table S4).