Epidemiology of Dengue Dengue Haemorrhagic Fever
Introduction, Historical

Introduction
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Prasert Thongchareon, M.D. and Sujarti Jatanasen, M.D.

00000000The exact date when dengue fever was first recognized in the world is still obscure. Descriptions found in the early literature include, perhaps, an epidemic of "knee fever" in Cairo and its suburbs in 1779 described by Al Jabarti(1), an epidemic in Asia occurring in the same year in Batavia (Djakarta) described by David Bylon(2) and an epidemic in Philadelphia, USA in 1780 described by Benjamin Rush(3).

00000000Since then, several outbreaks have been reported form all five continents. Geographical distribution of dengue fever is world-wide, involving nearly all tropical and subtropical countries, and it has many names, for example dandy fever, denguero, denga, dunga, bread bone fever, bouguet, seven day fever, bonon, chapenonada, Knieueble, Tok-kive-ana, Mal de genoux, homa mguu, and coup-d-barre.(4,5). Some unusual complications, especially haemorrhagic manifestations, have been described during epidemmics of predominantly classical dengue fever; for example, during the outbreads in philadelphia in 1780(3), in North Queensland in 1897(6), in Hawaii in 1903(7), and in Greece in 1927 - 1928(8).

00000000Classical dengue fever, as known for centuries, is characterized by fever, headache, joint and muscular pain in various parts of the body, skin rash and leucopenia. Generally, in young patients, dengue viral infection is usually mild or unrecognizable. However, during the last three decades many types of dengue syndrome have been frequently described(9). The mildest form is characterized by infection of the pharyngeal wall, mild rhinitis, coung and mild gastro-intestinal symptoms, and is diagnosed clinically as pharyngitis, influenza, influenaa-like discase, of even upper respiratory tract infection. The more severe forms are described as dengre haemorrhagic fever (DHF) and haemorrhagic fever with shock syndrome (DSS). Dengue haemorrhagic fever can be defined as an acute febile illness caused by one of four serotypes of dengue virus characterized by a haemorrhagic diathesis and a tendency to develop shock syndrome that might be fatal. Thrombocytopenia, with concurrent haemoconcentration, is a constant finding. The clinical entities caused by dengue viruses are summarized in Table 1(9).