IL6 and viral infectious disease: As shown in our previous studies, together with IL-6, IL-10, and IFN-γ, the cytokine patterns are helpful in discriminating bacterial and virus infection, Gram-positive and negative bacterial infection, and invasive pulmonary aspergillosis and pneumocystis pneumonia (Tang et al., 2011; Xu et al., 2013; Shen et al., 2016).