Dengue is the most important mosquito-transmitted viral disease in terms of morbidity and mortality.

Dengue fever usually affects people living in tropical regions and it manifests with a sudden episode of high fever.

More serious form of Dengue fever is called Dengue Hemorrhagic Fever (DHF) and Dengue Shock Syndrome (DSS) and affects a small proportion of patients who are affected by dengue fever. It is believed that there is a secondary infection by a different dengue virus serotype that leads to the development of DHF.

In Dengue Hemorrhagic Fever there is leakage of the plasma and its escape from the blood stream leading to bleeding. Lack of blood clotting is also observed. About 20-30% who suffer from DHF develop shock and this is known as Dengue Shock Syndrome (DSS).