In the same article, the neutrophil CD35-based differentiation between bacterial and viral infections was further improved by generating the Clinical Infection Score (CIS) point, incorporating four variables, the quantitative flow cytometric analysis of CD35 and CD11b (complement receptor 3, CR3) on neutrophils and standard clinical laboratory data, serum CRP level and erythrocyte sedimentation rate. Here, CR1 is linked to viral infectious disease.