Synonyms and related keywords: breakbone fever, ki denga pepo, mosquito-transmitted viral disease, febrile syndrome, bleeding diathesis, disseminated intravascular coagulation, DIC, dengue hemorrhagic fever, DHF, dengue shock syndrome, DSS, dengue viral infections, dengue fever.
Background: Dengue has been called the most important mosquito-transmitted viral disease in terms of morbidity and mortality. Dengue fever is a benign acute febrile syndrome occurring in tropical regions. In a small proportion of cases, the virus causes increased vascular permeability that leads to a bleeding diathesis or disseminated intravascular coagulation (DIC) known as dengue hemorrhagic fever (DHF). Secondary infection by a different dengue virus serotype has been confirmed as an important risk factor for the development of DHF. In 20-30% of DHF cases, the patient develops shock, known as the dengue shock syndrome (DSS). Worldwide, children younger than 15 years comprise 90% of DHF subjects; however, in the Americas, DHF occurs in both adults and children.
Dengue is a homonym for the African ki denga pepo, which appeared in English literature during an 1827-28 Caribbean outbreak. The first definite clinical report of dengue is attributed to Benjamin Rush in 1789, but the viral etiology and its mode of transmission via mosquitos were not established until the early 20th century.
Pathophysiology: Dengue viral infections frequently are not apparent. Classic dengue primarily occurs in nonimmune, nonindigenous adults and children. Symptoms begin after a 5- to 10-day incubation period. DHF/DSS usually occurs during a second dengue infection in persons with preexisting actively or passively (maternally) acquired immunity to a heterologous dengue virus serotype. Illness begins abruptly with a minor stage of 2-4 days' duration followed by rapid deterioration. Increased vascular permeability, bleeding, and possible DIC may be mediated by circulating dengue antigen-antibody complexes, activation of complement, and release of vasoactive amines. In the process of immune elimination of infected cells, proteases and lymphokines may be released and activate complement coagulation cascades and vascular permeability factors.
Race: Ethnicity is nonspecific, but the disease's distribution is geographically determined. Fewer cases have been reported in the black population than in other races.
Sex: No predilection is known; however, fewer cases of DHF/DSS have been reported in men than in women.
Age: All ages are susceptible. In endemic areas, a high prevalence of immunity in adults may limit outbreaks to children.
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