This alteration almost paralleled with the variation of serum IL-6 and TNF-α, which are proinflammatory factors and are reported to be elevated in severe HFMD.[1] Ooi et al have investigated several proinflammatory cytokines in HFMD and found that IL-6 and TNF-α are elevated in HFMD and that this elevation is consistent with the severity of disease.[1] This pattern was verified in our observations, and also by the fact that the IL-6 and TNF-α level increases were correlated with the severity of HFMD in the mild, severe, and critical groups (Fig. 1). The gene discussed is IL6; the disease is hand, foot and mouth disease.