IL6 and bacterial infectious disease: Frequently evaluated human biomarkers include C reactive protein (CRP), Procalcitonin (PCT), IL-6 and IL-8 for bacterial infections and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), interferon (IFN)-γ -induced protein-10 (IP-10) and myxovirus resistance protein A (MxA) for viral infections.