Dengue fever is characterised by a high fever phase and an abrupt drop in body temperature that has been called defervescence phase. Characteristically the disease outcome is defined during this phase, when patients can either recover rapidly or progress to a severe life-threatening stage. Cytokines and immunoactivation markers such as IFN-γ, IL-2, soluble CD8 and receptors for TNF-α [12, 29] are associated with the defervescence phase and with disease severity. IFN-α levels are higher in DHF than in DF during defervescence [30] .