CD4 and erythema multiforme: We also analyzed the correlation between the abundances of respiratory microbiota constituents at the species level and the clinical indices including gender, age, fever days, consolidate, pleural effusion, atelectasis, lung necrosis, respiratory failure, erythema multiforme, and lab indices including WBC, Neu%, Mon%, CRP, ESR, LDH, PCT, D-dimer, ALT, counts of CD3+ T cells, CD3+CD4+T cells CD3+CD8+T cells, CD16+CD56+ NK cells, and CD19+ B cells, and ratio of CD4+/CD8+ T cells (Figure 4).