One of its primary roles is to enhance hepatic gluconeogenesis, by activating the Janus kinase/signal transducer and activator of transcription 3 (JAK-STAT3) pathway in hepatocytes, resulting in the increased expression of gluconeogenic enzymes (G6P, and PEPCK) (83), contributing to hyperglycemia, which is mostly observed in severe viral infections and cytokine storm syndromes (84). This evidence concerns the gene STAT3 and viral infectious disease.