The clinical features on admission of fever (p = 0.01), low finger oxygen saturation (p < 0.001), low arterial partial pressure of oxygen (p = 0.02), increased indicators of inflammation including serum C-reactive protein (p < 0.001) and ferritin (p = 0.03), and low count of lymphocytes (p < 0.001) were associated with severe pneumonia expressed by a higher TSS score. Here, CRP is linked to susceptibility to pneumonia measurement.