CRP and infection: IL‐6 usually appears in plasma 30 min to 2 h after stimulation, reaching its peak at 4–6 h, with a half‐life of approximately 4–6 h18; PCT often appears in plasma 2–3 h after stimulation, reaching its peak at 12–24 h after infection, with a half‐life of approximately 20–28 h19; While CRP often appears in plasma 6–8 h after stimulation, reaching its peak at 24–48, with a half‐life of 19 h.19