CRP and viral infectious disease: Using a combination of MxA and CRP as indicators of infection, the ROC curve, sensitivity, and specificity for differentiating between bacterial and viral infections was 0.84 (95% CI: 0.75–0.94), 80.9% (95% CI: 66.7–90.8), and 87.9% (95% CI: 71.8–96.5), respectively (56).