Dengue virus is a flavivirus belonging to the family Flaviviridae. Its principal vector is Aedes aegypti, a highly urbanized, daytime-biting mosquito that breeds in stored water. There are 4 antigenetically variant serotypes of dengue virus, DEN-1 to DEN-4, and type-specific immunity against one serotype cannot block infection with another serotype. Disease manifestations following dengue infection range from subclinical infection to severe and fatal disease, with age, gender, genotype, immunologic status, and flavivirus infection history of the host all influencing disease severity. Primary infection is mainly associated with dengue fever (DF). Symptoms of DF typically appear 4 to 7 days after the mosquito bite and include high fever, headache, retroocular pain, conjunctival changes, and facial flushing. Although primary dengue infections are mostly recovered, a secondary infection with a different serotype of the virus leads to the complex condition of dengue hemorrhagic fever (DHF) with plasma leakage and thrombocytopenia or a more fatal condition, dengue shock syndrome (DSS). High fever, hemorrhagic phenomenon, hepatomegaly, and circulatory failure are mainly associated with DHF. Hemorrhages in DHF are seen in skin, subcutaneous tissues, heart, liver, and gastrointestinal tract. An estimated 50 to 100 million illnesses due to dengue infection occur annually, including 250,000 to 500,000 cases of DHF and 24,000 deaths. About 2.5 billion people are estimated to be at risk, particularly those living in tropical and subtropical areas of Asia and Latin America (reviews by Faheem et al. (2011), Whitehorn and Simmons (2011), and Guzman et al. (2010)). [from
OMIM]