Subsequently, the concentration of IFN‐γ was observed to be higher following the administration of the COVID‐19 vaccine than before vaccination, in both COVID‐19‐positive (median value: 5.35 IU/mL for OS and 1.87 IU/mL for VS) and negative groups (median value: 0.69 IU/mL for OS and 0.36 IU/mL for VS; Table 3). The gene discussed is IFNG; the disease is COVID-19.