GAPDH and viral infectious disease: In other words, the ratio of NS3/NS1 concentrations over time modulates GAPDH activity such that during the first 24 h of post-infection, the glycolytic pathway is activated to produce more energy for viral replication, and after this period of time, GAPDH activity is down-regulated, and cellular metabolism shifts to the synthesis of several metabolites that are also important for viral infection and propagation.