As illustrated in Fig. 5A–E, PCT exhibited the highest discriminative value with an AUC of 0.988 (0.969–1.000; P < 0.001), followed by IL-6 (AUC 0.917 [0.823–0.971]; P < 0.001), and CRS (AUC 0.916 [0.963–0.969]; P < 0.001). Here, IL6 is linked to congenital rubella syndrome.