Furthermore, the multivariate ordinal logistic analysis after adjusting for gender, vaccination date, and vaccination dose indicated that CRP at Days 4−7 (OR = 1.049, 95% CI = 1.005−1.096, p = 0.029), CRP at Days 8−14 (OR = 1.161, 95% CI = 1.015−1.327, p = 0.029), IL‐6 at Days 4−7 (OR = 1.203, 95% CI = 1.044−1.386, p = 0.011), total antibody (OR = 1.006, 95% CI = 1.002−1.010, p = 0.007) were risk factors for COVID‐19 severity (Table 4). This evidence concerns the gene IL6 and COVID-19.