Abstract
Dengue fever is being caused by Flaviviridae family and has four serotypes. The vector is mosquito Aedes aegypti and Aedes albopictus. Dengue fever also known as bone break fever. Primary infection with any one of the four dengue virus serotypes typically causing dengue fever (DF), which is a severe but self limited acute febrile illness, some primary infections and more of secondary infections with two different serotype results in very severe, debilitating and life-threatening DHF/DSS, which is characterized by increased vascular permeability and haemorrhagic manifestations. In rare cases of DHF/DSS, neurologic abnormalities, including encephalitis, may also occur. There are some evidence of other atypical manifestations of dengue fever as well such as a calculus cholecystitis, appendicitis, pneumonitis and myocarditis. Variations in virus strains within and between the four serotypes may influence disease severity. Secondary infections are more likely to result in severe disease and dengue haemorrhagic fever.