Severe HFMD patients with younger age; consciousness levels of sluggishness; lethargy or drowsiness; rashes with vesicles on the hands or feet; moderate or high fever; increased or disordered lung marking or pulmonary infiltration on chest radiograph; and abnormal HR, FPG, blood platelet, and CRP were associated with PICU transfer. The gene discussed is CRP; the disease is hand, foot and mouth disease.