Similarly, control patients with a diagnosis of bacterial pneumonia or other respiratory viral infections showed lower C5a and VCAM-1 concentrations compared to COVID-19 cases despite a slightly higher CRP concentration, whereas an increase in E-selectin concentrations was mainly observed in patients with bacterial pneumonia and was less pronounced in patients with other respiratory viral infections (Supplementary Tables 1, 2). This evidence concerns the gene C5 and bacterial pneumonia.