Dengue fever and dengue haemorrhagic fever are important arthropod-borne viral diseases. Each year, there are ~50 million dengue infections and ~500,000 individuals are hospitalized with dengue haemorrhagic fever, mainly in Southeast Asia, the Pacific and the Americas. Illness is produced by any of the four dengue virus serotypes. A global strategy aimed at increasing the capacity for surveillance and outbreak response, changing behaviours and reducing the disease burden using integrated vector management in conjunction with early and accurate diagnosis has been advocated. Antiviral drugs and vaccines that are currently under development could also make an important contribution to dengue control in the future.Dengue is the most important arthropod-borne viral infection of humans. Worldwide, an estimated 2.5 billion people are at risk of infection, approximately 975 million of whom live in urban areas in tropical and sub-tropical countries in Southeast Asia, the Pacific and the Americas 1 . Transmission also occurs in Africa and the Eastern Mediterranean, and rural
Europe PMC Funders GroupAuthor Manuscript Nat Rev Microbiol. Author manuscript; available in PMC 2015 February 19.
Published in final edited form as:Nat Rev Microbiol. 2010 December ; 8(12 0): S7-16. doi:10.1038/nrmicro2460.
Europe PMC Funders Author ManuscriptsEurope PMC Funders Author Manuscripts communities are increasingly being affected. It is estimated that more than 50 million infections occur each year, including 500,000 hospitalizations for dengue haemorrhagic fever, mainly among children, with the case fatality rate exceeding 5% in some areas [1][2][3][4] . The geographical areas in which dengue transmission occurs have expanded in recent years (FIG. 1), and all four dengue virus serotypes (DENV-1-4) are now circulating in Asia, Africa and the Americas, a dramatically different scenario from that which prevailed 20 or 30 years ago (FIG. 2). The molecular epidemiology of these serotypes has been studied in an attempt to understand their evolutionary relationships 11 .This Review will provide an update on our understanding of the pathogenesis of this successful pathogen, how we diagnose and control infection and the progress that has been made in vaccine development.
Dengue virus pathogenesisDengue viruses belong to the genus flavivirus within the Flaviviridae family. DENV-1-4 evolved in non-human primates from a common ancestor and each entered the urban cycle independently an estimated 500-1,000 years ago 12 . The virion comprises a spherical particle, 40-50 nm in diameter, with a lipopolysaccharide envelope. The positive singlestrand RNA genome (FIG. 3), which is approximately 11 kb in length, has a single open reading frame that encodes three structural proteins -the capsid (C), membrane (M) and envelope (E) glycoproteins -and seven non-structural proteins (NS1, NS2A, NS2B, NS3, NS4A, NS4B and NS5 [18][19][20] . ADE occurs when mononuclear phagocytes are infected through their Fc receptors by immune complexes that form between DE...