Dengue
Dengue fever is prevalent throughout the tropics, where the urban-dwelling mosquito Aedes aegypti is a major vector. The dengue viruses are the most widespread arthropod-borne viruses (arboviruses). During the 20th century, the distribution and density of Aedes aegypti expanded dramatically in tropical areas, beginning in large cities then spreading to the countryside. This was followed by global circulation of the four virus types.
Because there is no cross protection between different dengue viruses, an individual can be sequentially infected by different virus types. Most primary infections cause a debilitating, but nonfatal, form of illness. Some patients, particularly children but increasingly adults, experience more severe and occasionally fatal forms of the disease.
While vector control can show impact if systematically applied, most hopes rely on vaccines for the prevention of the disease. Vaccine development has been ongoing for decades, and has been hampered by the need to protect against all four viruses, as well as by concerns of immune-enhancement. Much progress has been reported over the past years, and several vaccine candidates are now in clinical development.
Further information
Last updated: 20 August 2012